Lca _environmental Profiles Methodology

CONTENTS EXECUTIVE SUMMARY 1 2 3

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5 6

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8 9

INTRODUCTION.................................................................................................................4 GENERAL PRINCIPLES ....................................................................................................5 GOAL AND SCOPE............................................................................................................5 3.1 Goal .................................................................................................................................5 3.2 Scope of the study...........................................................................................................6 3.3 Scope of data for impact assessment ............................................................................9 3.4 Data sources ...................................................................................................................9 INVENTORY DATA COLLECTION..................................................................................10 4.1 Defining the process .....................................................................................................10 4.2 Outputs ..........................................................................................................................11 4.3 Inputs .............................................................................................................................11 4.4 Emissions and discharges ............................................................................................12 INVENTORY DATA HANDLING:- ALLOCATION............................................................14 5.1 Explanation of allocation rules ......................................................................................14 5.2 Summary of rules for allocation.....................................................................................20 FURTHER INVENTORY DATA HANDLING....................................................................21 6.1 Rules and conventions ..................................................................................................21 6.2 Creating the generic Profile...........................................................................................21 6.3 Transport .......................................................................................................................23 6.4 Fuel................................................................................................................................23 6.5 Carbon cycle .................................................................................................................25 6.6 Adjusting carbon dioxide emissions for re-carbonation................................................26 6.7 Emissions ......................................................................................................................26 6.8 Imports...........................................................................................................................27 IMPACT ASSESSMENT ...................................................................................................28 7.1 Presentation of results: the Environmental Profiles......................................................28 7.2 The impact assessment process ..................................................................................28 7.3 Explanation of impacts on the characterised and normalised Profile ..........................29 REFERENCES .................................................................................................................33 ANNEXES .........................................................................................................................34 A1 AVERAGE GROSS CALORIFIC VALUES FOR UK FUELS - 1996..............................34 A2 FUEL USED IN ELECTRICITY GENERATION 1996 ....................................................34 A3 TOTAL AND UPSTREAM FUEL EMISSION FACTORS 1996......................................35 A4 PRIMARY ENERGY RATIOS FOR UK DELIVERED ENERGY - 1996 .......................35 A5 GROSS v NET CALORIFIC VALUES ............................................................................36 A6 STANDARD CONVERSION FACTORS AND UNITS....................................................36 A7 CARBONATION CALCULATIONS .................................................................................37 A8 TRANSPORT METHODOLOGY FOR CALCULATING FUEL USE..............................38 A9 SOURCES OF LCA DATA..............................................................................................41 A10 THE STANDARD QUESTIONNAIRE FOR INVENTORY DATA COLLECTION. .......42 A11 CHARACTERISATION FACTORS ..............................................................................49 A12 AN OVERVIEW OF THE ENVIRONMENTAL PROFILES DATABASE......................61 A13 INVENTORY PROFILE FORMAT ................................................................................63 A14 CHARACTERISED AND NORMALISED DATA PROFILE FORMAT .........................65

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THE BRE METHODOLOGY FOR ENVIRONMENTAL PROFILES OF CONSTRUCTION MATERIALS, COMPONENTS AND BUILDINGS This document is the result of over 3 years work in collaboration with representatives of the Construction Materials sector through a DETR Partners in Technology project. The following organisations have participated in the steering group for this project. It is the view of the majority of the members of this steering group that the methodology set out in this document is a practical, consistent and comprehensive method for the life cycle assessment of all types of building materials and components.

Aluminium Federation Brick Development Association British Cement Association British Lime Association British Plastics Federation British Non-ferrous Metals Federation British Precast Concrete Federation British Wood Preserving and Damp-proofing Association British Woodworking Federation Cementitious Slag Makers Association Celotex Ltd. Clay Pipe Development Association

Eurisol Forestry Commission Gypsum Products Development Association National Council of Building Materials Producers Nickel Development Institute Quarry Products Association Reinforced Concrete Council Steel Construction Institute Stone Federation of Great Britain Timber Trade Federation UK Forest Products Association Wood Panel Industries Federation

PEER REVIEW STATEMENT The following experts in Life Cycle Assessment and Building have undertaken a peer review of this methodology: Sverre Fossdal, Senior Researcher, Norwegian Building Research Institute. Tarja Hakkinen, Chief Research Scientist, VTT Building Technology, Finland. Jean Luc Chevalier, Head of the Environment and Durability Division, Materials Department CSTB (Centre Scientifique et Technique du Batiment), France. Wayne Trusty, Wayne B Trusty and Associates Ltd, Canada. They have confirmed that the choices used in this methodology conform with International Standard Organisation Guidelines ISO14041.

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EXECUTIVE SUMMARY Environmental Profiles are the result of over three years work undertaken in collaboration with representatives of the Construction Materials sector through a DETR Partners in Technology project. The work has been conducted to enable architects, specifiers and clients to make informed decisions about construction materials and components, by developing a method for providing independent, "level playing field" information about the relative environmental impacts of different design options. BRE believe that the collaboration between UK materials industries and BRE has resulted in a methodology that is unique worldwide in its consistent application of the LCA approach. UK materials producers should reap competitive benefits from the method, which sets a new standard for delivering this increasingly important aspect of product information. The work has achieved two significant results: this methodology document and a UK national database providing access to Environmental Profiles generated by the industry. The BRE Methodology for Environmental Profiles of Construction Materials and Components. The development of this set of common rules and guidelines for applying LCA to UK construction products enables materials producers in the UK to produce LCA data in the form of Environmental Profiles. Conformity with this methodology means that materials users can have confidence in the "level playing field" status of Environmental Profiles, for every material type. The Methodology document has been produced to ensure transparency of the methods employed in creating Environmental Profiles. This document describes in detail the consistent approach to the identification and assessment of the impacts of all construction materials and components over their life cycle, including: • • • • • • • • •

Standard goal and scope, Inventory data collection procedures, Preferred data sources, Consistent treatment of transport, Calculation of emissions from fuel use, Allocating impacts to products from multiple product lines, Adjusting Profiles for recycled content, Impact assessment procedures-for classification, characterisation and normalisation, Formats for Environmental Profiles.

Environmental Profiles of Construction Materials and Components. Profiles may be calculated for materials, components and building elements. The building elements Profiles can be presented "as built" or over a nominal life. • • •

Materials are presented as "cradle to gate" Profiles, on a per tonne basis. Installed elements are presented on a "cradle to site" basis and are calculated "per square metre" of element. Sixty year life elements are presented as a "cradle to grave" Profile, taking account of their maintenance, replacement and disposal rates for a sixty year life. These are also calculated on a "per square metre" basis.

Profiles which have been created over the life of the project are held in the UK Database of Environmental Profiles of Construction Materials and Components, which is available via an Internet service. Materials producers can add new Profiles for additional products at any time and the database will be regularly updated.

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BRE METHODOLOGY FOR ENVIRONMENTAL PROFILES OF CONSTRUCTION MATERIALS, COMPONENTS AND BUILDINGS 1

INTRODUCTION

Reliable and independent environmental information about building materials and components is in high demand. Environmental Profiles provide a useful way of providing this information. To be of help to the working architect, client or building specifier, this information must be produced according to an agreed methodology. This is a standardised way of identifying and assessing the environmental effects of building materials over their entire life cycle, through their extraction, processing, construction, use and maintenance and their eventual demolition and disposal. The reason for producing the agreed methodology is to ensure consistent assessment of different types of building materials, elements and whole buildings and to help the user by reducing the number of confusing claims about the environmental properties of alternative building products. This document is provided to ensure transparency of the method applied to create the data in the Environmental Profiles Database. It records the rationale and methodological rules that have been adopted by BRE to create a standard UK method of applying LCA to construction products and components. There is no single "right" answer for applying LCA but it is has been agreed by the majority of the building materials producers representatives in the project that this methodology represents a suitable approach to deal with all building materials. It is recognised that different approaches to LCA which can be applied to building materials may be equally valid and also meet ISO criteria. The BRE methodology has been devised with the particular aim of assisting decision makers to make comparisons between all types of building material from a "level playing field" perspective. Life Cycle Assessment (LCA) requires the collection of an inventory of data on all the inputs * and outputs of a process, i.e. the environmental burdens and their subsequent conversion into defined environmental impacts. This document provides a description of the basic principles that are applied in the creation of Environmental Profiles and is then structured around the different LCA stages that are undertaken to produce the Environmental Profiles. For each stage in the process a description of the work undertaken is provided. More information on LCA may be found in Guidelines 1. from SETAC, the Society for Ecological Toxicology and Chemistry (SETAC), which is a leading authority in life cycle analysis development, The different stages of LCA are: • • •

Defining the Goal and Scope Inventory Data Collection and Analysis Impact Assessment: Classification Characterisation Normalisation Weighting

*

The inputs and outputs to a system are called "interventions" under International Standard Organisation convention. In this document the term environmental "burdens" is used because we consider it to have more meaning for the user.

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GENERAL PRINCIPLES

The following principles are fundamental to every stage of BRE's application of LCA to building materials, components and buildings and encapsulate the philosophy and logic behind the method to be adopted: BRE's methodology aims to be consistent, scientifically robust and to ensure that burdens and impacts are completely accounted for without any double counting or undercounting. BRE's methodology aims to be consistent for all stages of the life cycle across all material classes – i.e. the winning of raw materials and fuels, energy conversion, chemical processes, manufacture, fabrication, transport, operation and use, repair and maintenance, refurbishment, demolition, reuse or recycling, disposal. BRE’s methodology must be permitted to evolve as our understanding becomes more refined. The field of environmental assessment is evolving rapidly and methods need to be updated at an appropriate rate. These principles represent the ideal and are often not reflected in existing databases, due to the difficulties of achieving them in practice. In BRE's work every endeavour has been made to comply with these principles. For practical reasons however, it is necessary in some cases to use data that is unknown with respect to these objectives. In such cases it must be ensured that the results are not sensitive to this data. 3

GOAL AND SCOPE

Whenever a life cycle assessment is performed, it is necessary to define why the study is being made and for whom. This is the goal. It is then necessary to define what will be included within the parameters of the study and what it is not possible or desirable to include. This is the scope. 3.1

Goal

Reason for carrying out the study To gather and assess comprehensive and reliable information regarding the positive and negative environmental impacts of construction materials used in defined applications, which are generated over a defined lifetime. Target audience Designers, specifiers and their clients and those involved in the production of LCAs for buildings. Intended use The data is intended to be used to improve the environmental performance of building designs, by allowing the designer to understand the impacts from different building elements and optimise the overall impact of a building design.

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3.2

Scope of the study

Boundaries Materials and components can be considered to have a lifetime from cradle to grave. The BRE method accounts for burdens and impacts on a cradle to grave basis. In other words, from the point when man exploits resources from the environment to the point at which the goods and services used become redundant and the materials and other effects return to the environment. In application, BRE results are also presented for some intermediate stages i.e. cradle to gate and cradle to site. If the scope of the assessment is declared cradle to gate, the investigation must trace production right back to the winning of all of the raw materials but does not include impacts beyond the factory gate. If the scope is declared as cradle to grave, then all of the processes from the winning of raw material through production, through use, reuse and recycling until eventual disposal within the environment need to be accounted for. "Gate to gate assessments" incorporate only one part of the production process and are considered to be potentially misleading because they may omit many of the largest impact phases of production. For example, the fabrication of a component might involve very high impact materials, but only incur modest impacts from a gate to gate assessment of the fabrication process alone. This type of scope would be useful for manufacturers wishing to seek process improvements. This is not a goal of the work described in this project but the rules A cradle to grave assessment appears at first sight to be the most complete and comprehensive and hence most justifiable. However, in making a cradle to grave assessment, large numbers of assumptions must be made about the use phase of the materials and products over typically very long timescales for buildings. For example, for insulation materials, their insulating properties will be far more important over the life of application than the impacts from the material production. In addition, scenarios of maintenance, repair and replacement must also be assumed and these can also have many times more effect on the life cycle performance than the initial production, especially over long life buildings. Different boundaries of assessment will be useful to different decision makers at different times and the methodology has been created to reflect these varied needs. The boundaries applied in this methodology are explained below for the different units of assessment available in the Environmental Profiles Database. Functional Units To understand the life cycle of a product, it is essential that it is considered in the context of its application - i.e. in its functional unit. Whilst materials and components can be considered to have a lifetime from cradle to grave, it is not possible to assign a life to a pile of bricks or tonne of insulation - they only have a true "life" when considered in the context in which they are used, e.g. as a wall. As a wall, or any other type of building element, building components do assume a life and they will fulfil various functions for a set amount of time, they will have maintenance requirements and will have to be dismantled at the end of their role in the building. Different materials can then be compared on a like-for-like basis, as components that fulfil the same or very similar functions. This means that important variables such as the mass of a material required to fulfil a particular function are therefore taken into account. For example, the results of a direct comparison between 1 tonne of steel and 1 tonne concrete would be misleading to a

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building designer. Instead the quantity of steel, and the other components, required to produce a square metre of steel wall should be compared with the quantity of concrete, and other components, required to make a concrete wall with a comparable function. The functional unit for construction materials has been chosen to be their typical as-built elemental form, over a service life of sixty years. Material and component data Other units of assessment may be useful for purposes other than that stated as the goal of producing Environmental Profiles. Per tonne data with a cradle to factory gate scope may be used for comparisons between identical products arising from different methods, or routes to production, or different feedstocks. It is also used to build up the Profiles of elements. The preparation of the per tonne inventory involves tracing all raw materials back to their extraction, describing the mode of transport and distance travelled to the processing site and the processing activities carried out there. The inputs and outputs to these processes are then identified. For some products, transport to a second site may need to be included as well as further manufacturing activity. Per tonne data is calculated for materials and components, for example “manufacture of one tonne of Portland cement”. This data comprises of information about the inputs and outputs involved in extracting, processing or making the input materials. These, plus the environmental burdens of actually making the cement itself, must be added together to achieve the full picture for a tonne of cement. Per tonne information provides the basic "building blocks" of Environmental Profiles and hence the database. When materials are considered per tonne however, they are not a functional unit and therefore they do not have a life cycle associated with them. For per tonne data, the boundary is defined as cradle to gate, therefore transport data to construction site is not included in per tonne data. Building element data In this project, Environmental Profiles for building elements will be created for a square metre of element. Data currently comes from the Profiles project, with supplementary data added where necessary Profiles are missing from the database. Two types of elemental data may be calculated: •

Installed elements

Per installed element data has a boundary of cradle to installation on site. This type of Profile allows the user to see the overall burdens of different components in specific function but require the user to apply their own life time factors. •

Sixty year elements

The functional units must have an anticipated lifetime and maintenance programme if replacement and maintenance factors are to be taken into account. Environmental Profiles for per sixty year building elements will again be for a square metre of element, as for installed elements, but determined for the life of the element in a typical building of 60 years. This data has a scope defined as cradle to site over a 60 year life. The lifetime includes consideration of environmental aspects from gate to grave, within the limitations of current knowledge. For this methodology, a BRE study into information available2 has resulted in the following boundaries for cradle to grave Profiles which affect the collection of data

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between the factory gate and the end of life. These assumptions will be investigated in further research. • Boundary assumption 1: Construction impacts This first edition of the methodology does not include construction impacts. This is because the documentation of impacts arising on site is very poor and more studies are required to provide meaningful information. The energy used in construction is estimated to be 0.5% of the UK national energy use which can be compared to the small but significant proportion of annual national energy used to generate building materials for new buildings, which is estimated to be between 5 - 6% 3. • Boundary assumption 2: Life Time Use: Maintenance Painting and varnishing maintenance is included, by considering the quantities of materials used, but not the associated transport for achieving the maintenance. Cleaning and other forms of maintenance are not included in this edition of the methodology. • Boundary assumption 3: Life Time Use: Replacement A set of replacement factors has been calculated based on best information sources available today. This pragmatic approach is intended as the basis for the factorial service life prediction techniques in progress by ISO. It means that, for our 60 year office building, if an element has a service life of only thirty years, then all the impacts are doubled. No allowance is made for materials that will last, say, forty years and then have an "excess" service life of twenty years from the point of replacement, over the designated sixty years. If a component in an element is expected to fail before sixty years and can be replaced without removing the rest of the element, then only the impacts associated with that particular component will be replaced. If other components of the element, or the entire element, must be replaced because of the shorter lived components, then their cradle to grave impacts will be multiplied by the replacement, even if the materials removed have a potentially longer lifetime. •

Boundary assumption 4: Life Time Use: Contribution to Life time Energy Use in a Building All buildings are built to meet building regulations and achieve the minimum U-value. All the element specifications have been chosen because they achieve this requirement. This allows the designer to consider the overall impact from quantities of different materials required to produce different building solutions. For example, the merit of more insulative wall materials is made explicit because less insulation material is included in the prepared element, which has been designed to meet the desired U-value. • Boundary assumption 5: Demolition This first edition of the methodology does not include demolition impacts or waste removal impacts. • Boundary assumption 6: Disposal The boundary ends at the point at which the quantity of materials sent to disposal - to landfill or incineration - is calculated. The mass of any materials known to be reused or recycled is excluded from these waste burdens. Only the CO2 and methane emissions from incineration and landfill can be included in the Profile at the present time. Where appropriate, the reduction in volume from incineration, but including the volumes of ash produced, is included in the quantity of waste to landfill. If appropriate, following further research work at BRE in 1999/2000, a new method of attributing per tonne waste disposal environmental burdens will be added to the Profile of the building element.

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3.3

Scope of data for impact assessment

The long term aim of this work is to comprehensively account for all of the key parameters of environmental, economic and social impact including land use, resource consumption, energy, labour, capital, the consequential pollution to air, water and land and the resulting ecotoxicity and human toxic impacts, the wastes arising for disposal and their potential for reuse and recycling. Currently, the work is restricted to environmental impacts from: Energy, Minerals and Water consumption, Waste, Air and Water emissions. These are generally considered to be the burdens most relevant for construction materials. Land use and biodiversity issues are important omissions from this list. These and others may be added into future editions as the methodology evolves. The list of issues and their measurement units will need to develop and be updated progressively as knowledge and methods improve. 3.4

Data sources

Preferred sources 1. Detailed process information obtained directly from a reasonable sample of manufacturers of UK building materials, products and components. 2. Industry-generated average figures without data separately identified from individual companies. Where industries supply data collected as part of a previous LCA study, full details of the rules and conventions used in the study have been sought and the BRE methodology applied. 3. For substances and products which have a significant input to a process but for which data cannot be readily obtained from the suppliers, data has been obtained from existing commercial databases (sources used are fully referenced in Annex 9). Data quality Data in Environmental Profiles is accompanied by descriptors relating to sources and collection methods. See Profile format, Annex 13 and 14. BRE will endeavour to make random checks on data providers to verify the sources and estimation methods used to derive data. Ultimately, however, the database relies upon the quality of data provided by industry.

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INVENTORY DATA COLLECTION

This chapter contains the guidelines for compiling the inventory. To compile the inventory, the boundaries of the process must be defined and then data about inputs and outputs to the process collected. 4.1

Defining the process

For all data provided for the UK National database, a comprehensive process tree should be provided including any major transportation stages with a clearly marked system boundary to indicate the included from the excluded processes. The resulting inventory should balance in mass terms and in energy terms (taking due account of any phase change processes like evaporation in order to be thermodynamically correct. The only exception is nuclear processes where mass and energy must collectively balance). In other words, the total energy or mass flowing into the system boundary must be accounted for with an equivalent mass or energy flow out of the system boundary. Figure 1 provides a standard format for creating a process tree. Figure 1 Generic Process Tree

Inputs

PROCESS 1

OUTPUTS

tr

tr

PROCESS 3 (ETC)

Inputs

OUTPUTS INCLUDING FINAL PRODUCT

PROCESS 2

Inputs

OUTPUTS

tr

Transport

Annex 10 gives a standard questionnaire suitable for data collection when creating Environmental Profiles. The inventory comprises the following items: Inputs:

Outputs:

Materials Transport Fuel Process Fuel Water Emissions to air Discharge to water Emissions to land

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Guidelines for the collection of data for each inventory item are given below. Details of how the data should then be manipulated to provide the per tonne inventory are given in section 5, "Inventory Data Handling" 4.2

Outputs

Information on all outputs from the process, including any co-products, by-products and materials sent for re-cycling/re-use/re-processing should be provided. This includes any output which is sold, recycled or re-used in any way, such as waste oil, packaging sent for reuse and by-products such as slag from iron production. Where data on inputs or emissions have been given which apply to more than the product being considered for the Profiles project, e.g. total factory output or product and co-product, then effort should be made to identify the emissions associated with the product under consideration. If this is not possible, the methodology requires that the burdens of production are allocated to the products according to economic value. Relative values of the product to all relevant outputs should therefore be provided where necessary. Information on the allocation procedure is given in greater detail in Chapter 5. 4.3

Inputs

Inputs to the process that are measured in the inventory include the materials associated with the manufacture of a product and also the consumption of fuel and water. a) Materials The inventory process gathers all the inputs to the plant that are associated with a product, including product ingredients, packaging materials and consumable items. Criteria for significance For many processes, a large number of substances and materials are used in very small quantities and it would be unrealistic to gather data on all of these. However, it is important that significant environmental effects are not omitted by ignoring these low mass substances. Sensitivity analysis may later reveal that these substances do not significantly affect the overall result but it is important that data is provided to enable this conclusion to be drawn. To achieve this, the following conventions are applied: Data should be included for 98% of all inputs by mass. Data should be included on all materials with a mass greater than 2% of the output from the process. Information should also be provided for materials which contribute less than 2% by mass, but possibly have: • • •

significant effects in their extraction, their use or disposal, or are highly toxic, or classed as hazardous waste.

Materials with a low mass input but which contribute a significant proportion of the energy input should also be included. For example, the adhesives which are used in the manufacture of window frames are integral to the product and should be included even though they account for less than 2% of the output (by mass).

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b) Transport of materials to the plant Data on transport to site should be collected for all the input materials, including fuels delivered to the site (excluding electricity and pipelines). This may be achieved by more than one mode of transport. These should be listed, including size and type, along with the average distance travelled, the number of deliveries per year, average delivery weight, and what is carried on the return journey (or percentage part load). Where more than one supplier is used, estimates of the tonnage from each should be made and information provided about each one. c) Direct consumption of fuel The inventory requires the total quantity of each fuel used by the plant for one year, including fuels used for heating and lighting in buildings. To ensure all fuels are included, the purpose for using each fuel should be recorded. Space heating and office fuel use should be included. Only vehicle fuels used for transport on site should be included. Fuel from off site transport is calculated separately. If electricity is not purchased from the national supply, its source should be given. The calorific value of fuels such as wood residues, secondary liquid fuels (SLF) and landfill gas should be included. Inherent fuels such as fletton clay and fuels obtained from recovery processes such as blast furnace gas or waste wood should also be included. Information about the transport mode and distances to deliver fuels to site should be provided in b) "Transport of materials to plant." d) Water use The inventory must include the water brought into the plant each year in terms of the total quantity used and, where possible, the quantity per tonne of product. It is useful to distinguish water purchased from water company and private supplies of surface and ground water. It is also important to distinguish water use from water abstracted to ensure any recycling of water is recognised within the Profile. This will mean that the recycled water is not given a burden for extraction every time it is used. e) Capital equipment Although it is a form of indirect energy input into the process, the contribution of capital equipment is not normally considered in LCA and it is not included here. Maintenance of equipment, including use of lubricants, is also not included in the LCA. Frequently "consumed" items such as saw blades and sanding paper and mould oil are included in the inventory. 4.4

Emissions and discharges

The inventory includes a record of the quantities of each substance of interest associated with the manufacture of one tonne of the material or product. Emissions from industries considered in this methodology include those resulting directly from processes and those resulting from fuel use. Some emissions are measured by the industry, others may be calculated in the preparation of the inventory from standardised conversion factors (see the next section). Others may derive from assumptions made about the process, e.g. the CO2 produced by the heating of carbon containing minerals such as limestone, from theory based on chemical composition. If emissions are measured and calculated on an annual basis for Integrated Pollution Control (IPC) authorisation, then these values may be used and allocated appropriately. If such values are not available, then the results of other measurements should be supplied. Estimates should be accompanied by a clear explanation of their origin.

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Emissions from a plant may be from more than one product. If emissions are known to arise from specific products, by causal relationship, then these should be provided together with a description of the method used to identify the emissions. If this is not possible, emissions for the whole plant should be provided. Accidental emissions are not included. Negative emissions of substances, e.g. sequestration of CO2 by growing plants or re-carbonation of lime should be included (see sections 6.5 and 6.6.). a) Emissions to Air In theory, it is only necessary to record emissions to air resulting directly from the process and as a default, emissions arising from fuel usage will be calculated separately, using standard emission factors. It is important to note however, that emissions of NO x , CO and VOCs are dependent on the efficiency of combustion and emission control techniques may have been fitted for SOx and PM10 emissions. Therefore, if these emissions are measured at a plant, these measurements should be provided to give a more accurate inventory. b) Discharges to Water Inventory information is collected on the total quantity of water discharged to both the sewer and to surface water (fresh and marine) each year. Both average values and ranges should be provided for the concentrations of BOD, COD and suspended solids discharged to both sewer and surface water, as well as the sampling procedure used. Other measured emissions should be provided. c) Emissions to land Waste is defined in this project as a product of a manufacturing or processing stage which the manufacturer considers has no value and no purpose in that part of the process. It includes particulates collected from gas streams and de-watered sludge and solids from treated effluents. It is important to identify those materials that manufacturers consider to be waste separately to those which they treat as co-products and by-products such as slag from iron production and bark from wood processing. Information is required on the categories, quantities and final destination of both controlled wastes and those which are not controlled, e.g. mine overburden waste from mining and extraction operations and furnace slag, ash, bark and sawdust which is not reused or sold on from processing operations. Information on controlled waste can be collected from 'Duty of Care' transfer notes. It is important to provide as much detailed information as possible about the content and the destination of waste. Information should be provided on the quantities produced per year of the three main categories - Controlled Commercial, Controlled Industrial, Controlled Special - as well as a list of the main materials in the description of the wastes produced. For raw materials extraction, there is an additional category, mine and quarry waste, which should be used. For special waste, the National Waste Classification Codes and Hazard Property Codes 4 should be given where possible. Data should be provided on the route(s) for disposal which are in current use. The potential recyclability of a product is not considered at the data collection stage - see Chapter 5.

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5 5.1

INVENTORY DATA HANDLING:- ALLOCATION Explanation of allocation rules

Allocation for Linked Processes Figure 2

Allocation principles RETURN Σ v.t

WHY THE PROCESS EXISTS Capital Investment £C

t1 Process P Inputs

t2 t3

P r o d u c t 1 w o r t h £ v 1.t1

Allocate P . v 1 .t 1 / Σ v.t

P r o d u c t 2 w o r t h £ v 2.t2

P . v 2 .t 2 / Σ v.t

R e c y c l e d w a s t e £ v 3 .t 3

P . v 3 .t 3 / Σ v.t

R e c y c l e d w a s t e £ 0 . t4

P.0.t 1 / Σ v.t

t4 Wastes

A unit process is supplied with inputs and generates output products, by-products and recyclable wastes all of which might find application in further processes, together with wastes which must be disposed of and pollution which must be carried by the environment. An allocation rule is needed to assign the burdens appropriately between the co-products and reusable or recyclable wastes. ISO 14040 recommends a series of priorities for allocation as follows: Avoid, by division of a single process into sub-processes By system expansion to avoid allocation. By physical property (e.g. mass or calorific value) By product value BRE has used the following, in order of preference: Avoid, by division of a single process into sub-processes By physical property By product value BRE recognises the desirability of avoiding allocation and therefore separates processes into sub-processes to avoid allocation wherever possible. To achieve the goal of the BRE study it is necessary to have a standard method of LCA for all materials. To achieve a common approach to allocation, wherever physical data is available to divide between two processes, then this information will be used to allocate between multi-product processes. However, where physical data is not known there is a requirement for a further method that can be applied to all materials. It is not possible to use system expansion for all materials because alternative products must be available for which the by products from a system can

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be substituted and this does not apply to all materials. BRE consider economic value to be an effective and appropriate method of allocation which can be applied consistently to all materials where avoidance or allocation by physical property cannot be applied. Where two product streams come from a single process (or inseparable parallel processes), and physical data is not available, BRE will allocate burdens according to the proportion of product revenue earned from the two product streams. This rule is considered to be justified because the producer has invested in setting up the process(es) and expects to earn revenues from the product streams. Accordingly the value of the product streams is considered the most appropriate basis for allocation since it assigns the burdens in proportion to the product streams contribution to profits arising from the process(es). See Figure 2. The price that is used to make the allocation is the average three year market price of the relevant materials. If process 1 and 2 are sequential processes, with all product 1 used as an input for product 2, all of the inputs, wastes and pollution for both processes can be added together, product 1 can be ignored and all of the burdens can be assigned to product 2. This is called expanding the system boundary so that the two processes can be treated like a single process. For sequential processes, it is acceptable to expand the system boundary to account for them collectively. See Figure 3. Figure 3

Sequential processes Input 1

Process 1

Product 1

Process 2

Product 2

Input 2 Expand boundary so all Inputs for Product 2 = Input 1 and Input 2

If only part of the output from product 1 goes into process 2 then only the appropriate proportion by mass of the burdens going into process 2 should be passed on to process 2 and assigned to the production of product 2. The remainder of these burdens should remain with the balance of product 1. Figure 4 shows that if process 1 and 2 are operated in parallel in a single production facility, they should as far as possible be treated as separate processes and the inputs, outputs, wastes and pollution calculated separately for the two processes. In practice, however, it may often not be possible to distinguish the processes, especially where they share common feedstock or fuel sources that are not separately metered. In cases where the data cannot be separated for the two processes, the system boundary can be expanded to encompass both processes, and allocation by product stream value will be used to allocate burdens between the products.

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Figure 4

Two processes in parallel Process 1

t1

Process 2

t2

Product 1 worth £v1.t 1

Allocate P.v1.t1 / Σ v.t

Inputs Product 2 worth £v2.t 2

P.v2.t 2 / Σ v.t

1. Try to separate the processes and determine their profiles. 2. ONLY IF 1 IS NOT POSSIBLE combine the profiles for the processes and use allocation by value.

Recycling and allocation In assessing recycling, three issues need to be addressed: 1. To avoid double or undercounting, the method must EITHER distinguish recycled, reused and primary products to today’s decision taker OR combine recycled, reused and primary over a material’s cradle to grave multi-life-cycle (which may comprise a succession of different products). 2. How to allocate impacts between recycled, reused and primary product from process scrap, home scrap or end use scrap or wastes. 3. Whether to reward a product today for its recyclability over very long building timescales (perhaps over hundreds of years for several recycles) OR focus upon only today’s decision-making and current recycling and recycled content. BRE have chosen to resolve these issues by adopting the following rules in the Environmental Profiles methodology. Distinguishing recycled, reused and primary products Of the two approaches described in 1) above, distinguishing recycled, reused and primary products to today’s decision taker is the preferred approach by BRE in that it distinguishes the recycled and reused products in the market place and allows users to show a preference for (and presumably pay a premium price for) the lower environmental impact product. However, it is recognised that the second approach is useful for comparing products made from comprehensively recycled materials such as metals with those made from inherently non-recyclable materials. Hence, BRE accept that for particular comparisons, it may be appropriate to use the second method, but where all construction products are being assessed to a common methodology, as for the Environmental Profiles, the first method is preferred.

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Allocation for recycling and reuse Expanding the system boundary is an appropriate way to account for closed loop recycling in sequential processes. If material is recycled between sequential process stages (as in Figure 5 - closed loop recycling or “recycling into the same process”), then expanding the system boundary to incorporate the recycling processes is considered the best way of accounting for this. Figure 5

Recycling into same process Process P

tp. v p

Use

t r .v r

Primary production = P ( 1 - y ( v r/ v p ) ) + y (v r / v p ) ) = P ^added from recycled ^deducted from primary for recycled. yield y

However, if (as in Figure 6) material is taken out of the system boundary, then the recycled material has to be treated separately. Where scrap arises from post consumer use (old scrap), it is not considered appropriate to expand the system boundary to take account of scrap arising. To do so requires a comprehensive scenario of use, repair, maintenance, dereliction and reuse and recycling to be assumed over very long timescales. It would be difficult to be confident that all parties in the chain of decision making would consistently comply with the assumptions made, especially over such long periods. A similar approach to Figure 6 is therefore taken as if a separate recycling process is undertaken to recycle material, rather than adding this material as an input to the primary production (Figure 7). Figure 6

Recycling into another use Inputs

Process P

Primary production = P ( 1 - ( t r .v r)/( t p . v p ) ) o r P ( 1 - y ( v r/v p ) ) ^deducted from primary for recycled. yield y

tp . v p

Use 1

Use 2

t r. v r

Recycle R

Recycled production = R + P ( ( y .v r /v p ) ^share of primary in 1st recycle If the recycled material has no value, then none of the impacts from the first process are attributable to the recycled product.

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Figure 7

Separate recycling process Inputs

Process P

Primary production = P(1-(tr .v r )/(tp . v p )) or P(1-y(v r/v p )) ^deducted from primary for recycled. yield y

tp .v p

Use

t r .v r

Recycle R R 1 , R 2 ..R n

Recycled production = R(1- (y.v r /v p ) n ) + P((y.v r/v p ) n - (y. v r /v p ) (n+1) ) ^share of primary in n recycles ^share of recycled in future recycles For infinite numbers of recycles = R

Wastes or recycled products from open loop recycling will be allocated burdens based on the residual value of the waste stream compared to the value of the process product (and waste) streams. The same approach can be applied to allocating burdens to wastes or recycled products from open loop recycling as between products and co-products based on the value of the waste stream. This approach allocates a proportion of the impacts from production to the wastes that arise, in proportion to the residual value of those wastes compared to the value of the original products (and wastes). In this way, the burdens assigned to the product are effectively assigned to the use of the product over its life. At the end of the useful life of the product, it becomes a redundant liability unless it retains some inherent value. The burdens assigned to a valueless waste stream would be zero, but if a product retains some value then it ought to carry some of the burdens of its production onto the recycling or reuse phases. The proportion of burdens carried by a waste into the future are then subtracted from the burdens assigned to the primary product. Mathematically, this is completely consistent with the closed loop recycling principles and expanding the system boundary because any burdens retained by closed loop recycled product (which are subtracted from the primary production) are added again when the scrap returns to the process. The method also works for waste recycled into new construction materials production. If the waste has a market value, then it should attract a proportion of the burdens from the process. These are in turn subtracted from the burdens for producing the other products. This approach appears to give very sensible results. Producers that consume PFA from power stations would attract less than 0.02% of the burdens from electricity production because PFA is of such small value compared to the electricity as the main product . The PFA that is sold receives a proportion of the impacts of electricity generation, including a proportion of the burden of PFA sent to landfill, according to its market value. Hence, all of the materials arising from a process that have a financial value attract a proportion of the burdens associated with the production processes. This approach is entirely consistent, avoids double or undercounting and assigns burdens in proportion to the value paid and therefore perceived by society for the materials and products.

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Figure 8 demonstrates an important feature of the recycling methodology. "Home scrap" is scrap which arises from further fabrication processes but is not "post consumer" scrap, otherwise known as "old scrap". In this methodology, home scrap is considered to arise within the expanded boundary of the production process. Only old scrap is considered to have left the system and is thus available to reduce the impacts of the production process through recycling. Figure 8

Recycling home and new scrap Inputs

Process P1

“home scrap”-->

Process P2

Use

“new scrap”-->

“old scrap”-->

Recycle R

For “home scrap” and for “new scrap”, expand the system boundary. Only “old scrap” should attract any recycling discount from the production processes .

3 Recyclability or Recycled Content BRE will base its consideration of the recycling or reuse properties of a material or product on current recycling achievement. The rationale for this approach is as follows: Traditionally, we have thought about recycling as something that happens at the end of the life of a material or product. If we take account of recyclability, we must rely on decision takers in the future responding to our predictions and on markets wanting to use these materials into the future. For many high value materials, there is a strong historic precedent for justifying this assumption. However, for many newer materials e.g. plastics, it has been difficult to establish and sustain markets for recycled product and for some materials or products there are questions about degrading quality and performance. In addition, many materials or products are recycled into different materials and products for later uses. Finally, because buildings last for so long, it is impossible to imagine what innovations in recycling techniques, in building products which use recycled material and the changes in market values for different scrap materials and wastes. Hence, there is very large uncertainty about the real scenarios for recyclability. An alternative view of recycling is to consider it as the first stage in the production of a recycled product and starts right now with the effective mining of raw material from waste streams and results in a product that can be distinguished in today’s market place for its recycled content. This view of recycling is entirely contemporary and doesn’t rely on a succession of decision takers to deliver consistent action for possibly hundreds of years into the future. The performance of today’s products can be reflected to today’s decision taker acting in known market places with known recyclability performance. This approach also

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has advantages in that it can consistently use the same allocation rules based on the value of product or waste streams without the complications of discounting for future values. BRE will use recycled content as the basis for its methodology together with consistent allocation rules based on the value of current waste streams. In most cases, recycled material will attract no burdens from earlier phases of production. Recyclability cannot be considered consistently with this approach. 5.2

Summary of rules for allocation

Allocation for products and co-products • Allocation rules are needed to assign the burdens appropriately between products, coproducts and reusable or recyclable wastes from a process. •

Where two product streams come from a single process (or inseparable parallel processes), burdens are allocated according to the proportion of product revenue earned from the two product streams.

•

For sequential processes, it is acceptable to expand the system boundary to account for them collectively.

•

If only part of the output from a product 1 goes into a process 2 then only the appropriate proportion by mass of the burdens going into process 2 should be passed on to process 2 and assigned to the production of product 2. The remainder of these burdens should remain with the balance of product 1.

•

If two processes are operated in parallel in a single production facility, they should as far as possible be treated as separate processes and the inputs, outputs, wastes and pollution calculated separately for the two processes.

•

In cases where the data cannot be separated for the two processes, the system boundary can be expanded to encompass both processes, and allocation by product stream value will be used to allocate burdens between the products. This is the price at which the product is sold by the manufacturer and should be based on 3 year average prices.

Allocation for recycling and reuse • Wastes or recycled products from open loop recycling are allocated burdens based on the residual value of the waste stream compared to the value of the process product (and waste) streams. •

The proportion of burdens carried by a waste into the future are then subtracted from the burdens assigned to the primary product.

•

Hence, all of the materials arising from a process that have a financial value attract a proportion of the burdens associated with the production processes.

•

Where repeated recycling occurs, for example for metals, the primary burden carried forward through each recycling decreases until after an infinite number of recycles it reaches zero.

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6 6.1

FURTHER INVENTORY DATA HANDLING Rules and conventions

Raw inventory data collected from manufacturers must be modified to produce standard data in an Environmental Profile. The process is as follows: • Data is converted to standard units, e.g. MJ for energy, Tonnes for inputs. • Conversion figures for transport, into emissions to air and fuel consumption will have been applied • Conversion figures for fuel will have been applied into emissions • Additional figures will have been incorporated to fill in missing data from plants (with the approval of data providers) and to expand the data to include later stages in the life cycle of the product. • Allocation procedures will have been applied to obtain burdens for the main products and by-products etc. • Transport figures will be calculated to provide data on product delivery to site. • Where appropriate, lifetime data on maintenance and replacement will be added, at first using readily available information and professional rules of thumb. Additional information will be acquired from the further BRE study of life cycle impacts. • The data will have been normalised to per tonne levels. • Generic UK figures will be calculated where individual site data have been provided. The basic procedure to produce a per tonne datasheet is: • • •

Check data-using mass balance, process diagrams. Process data to standard units [ given in Annex 6]. Apply Input and Output inventory handling procedures.

The checklist in Table 1 describes the inventory data handling procedures for converting each inventory item to per tonne data items. This is followed by a more detailed explanation of how generic Profiles are produced. 6.2

Creating the generic Profile

Where data is available from a number of sites for a product group, the generic product for the UK is arrived at by applying an average based on the proportional contribution of each site by mass to the total UK mix of the sites supplied, where known. In a small number of cases the generic figure is derived from one site. It has already been noted that upstream data, i.e. data about inputs into a process, has been obtained from within the Profiles project where possible, but that important data gaps in manufacturing data sets that we cannot fill from partners will be filled using data from best available sources. These are primarily from IVAM, Pré, BUWAL, ETH and SBI data, listed in Annex 9. Further data may also be found from other sources, using the most recent and geographically applicable data as a preference. Wherever possible, all additional data is allocated according to the principles outlined in this document. Considerable effort has been made to check and compare the accuracy of additional data to UK production and other sources of data. Where possible, the UK fuel mix for electricity generation, together with associated emissions have been applied to the additional data. A lack of transparency in the inventory may prevent this.

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Table 1: Inventory data handling checklist OUTPUTS • Output materials: 1) Define Principal product for per tonne Datasheet 2) Include all other Products and By products 3) Include all materials sent to recycling 4) Divide outputs by product output in tonnes to obtain per tonne data. 5) Obtain relative values of all Outputs Use relative values to allocate

-------------------------------------------------------------------------------------------------------------------------INPUTS • 1) 2) 3) 4)

Transport: Check total inputs, loads, vehicle sizes and number of deliveries correspond. Allocate to principal product. Apply method for fuel consumption and emissions to air (see Annex 8). Divide by principal product output in tonnes to obtain per tonne Data.

• Fuel: 1) Convert quantities to MJ 2) Allocate to principal product 3) Divide by principal product output to obtain per tonne data. 4) Use standard conversion factors to obtain Primary Energy value. 5) Use standard conversion figures to obtain Fossil Fuel Depletion value. -------------------------------------------------------------------------------------------------------------------------------------• Water Use, Supply and Discharge: 3 1) Convert quantities to M 2) Divide by product output to give per tonne data. Note: use of recycled water is accounted for by considering total water use and total output. --------------------------------------------------------------------------------------------------------------------------------------

EMISSIONS • Emissions to Water 1) Cross check with Chemical Release Inventory 2) If concentration is given, multiply by water discharge to obtain mass 3) Allocate to principal product. 4) Divide by principal output in tonnes to give per tonne data -------------------------------------------------------------------------------------------------------------------------------------• Emissions to Air 1) Calculate emission for each fuel using Standard Conversion factors. 2) Ensure process emissions are included. 3) If chimney emissions have been given, check which fuels these apply to and ensure that there is no discrepancy between calculated emissions and given emissions (taking account of efficiencies and attenuation, e.g. FGDS) and substitute chimney emissions. 4) Cross check with Chemical Release Inventory 5) Allocate to principal product 6) Divide by product output in tonnes to obtain per tonne data 7) Aggregate data together with Emissions to Air arising from Transport.

-------------------------------------------------------------------------------------------------------------------------• 1) 2) 3) 4)

Emissions to Land Includes Solid and Liquid emissions to Landfill and Incinerators (and Mine and Quarry waste etc.) If incinerated on-site, give details of incineration emissions and any heat recovery. Allocate to principal products Divide by product output to obtain Per tonne data.

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6.3

Transport

Transport to factory gate The environmental burdens arising from the transport of raw materials and other goods to manufacturing sites are included within the unit process for that material or component. For example, the transport of clay to a brick manufacturing plant, or the transport of processed timber to a window manufacturer are included. Transport fuel data is calculated using the mix of transport modes used by an industry and the average loads and sizes of vehicles. The method incorporates mode, distance, vehicle size and return loads. See Annex 8 for details of calculating Road, Rail and Shipping fuel consumption. Transport to site Standard values will be assumed for each material or component. In life cycle software tools, it should be possible to change this "default" to take account of local conditions. In the absence of better data, the standard values for transport to the construction site from the factory gate is based on "average" haulage journeys for each material in the UK, as collated by DETR. It is assumed that there is an average loaded journey from the final fabricator to the site and that the return journey is empty and of average length. Using fuel consumption figures for different types of lorry, and the total distance travelled, the fuel used and associated emissions can be calculated. The loaded distance travelled in order to transport 1 tonne of product gives tonnes kilometres. Transport to site is not associated with per tonne figures. It is incorporated into the figures for installed and sixty year life elements. 6.4

Fuel

Primary and delivered energy For any manufacturing, transportation or heating process, energy is supplied from a number of different sources used as fuels, including waste materials. The data collected on the quantities of this energy used in a process provides a value for the ‘delivered’ energy (called ‘process’ energy in ISO). However, all fuels suffer losses and fuel expenditure in their extraction, their refining, and their supply and transmission, and require energy expenditure to extract, refine and distribute them. So that the full impacts of manufacture and processing can be assessed, the quantities of each form of delivered energy and fuel must be adjusted to take account of these losses. Values for delivered energy corrected to take account of the production and delivery losses and expenditure are known as ‘primary’ energy. The factors which will be used by BRE for conversion of delivered energy values to primary energy are given in Annex 4. Values are also given for the current fuel mix used in the UK for the generation of electricity, Annex 1 and 2. Fuels of no economic value, e.g. oil within fireclay and "town ash" are considered to have a primary energy value because the energy to win these fuels is considered in the inventory when they are used. Their transport to the place of consumption, i.e. factory, contributes to the energy consumption of the final product but is not included in the "primary energy" of the fuel, as for standard fuels. Primary energy is provided as a data item in the Inventory Environmental Profile. The primary energy is equivalent to the "embodied energy" figure for a material or element. The environmental impact of energy use arises from depletion of available fuel resources, or emissions from burning them. The emissions to air do not derive solely from the use of fuel, but fuel combustion is a major contributing factor. Energy use in the characterised Profile is also represented by Fossil Fuel Depletion. Fossil fuel depletion is measured in Tonnes of Oil equivalent (toe), which is an amount of energy equal to 41.83 GJ. It is calculated by converting the primary amount of fossil fuels, such as coal, oil and gas,

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used to provide the delivered energy into toe. Further details of this characterisation factor are given in section 7 and Annex 11. Calculation of energy-related emissions Carbon dioxide, sulphur oxides and nitrogen oxides are produced by each type of delivered energy, e.g. electricity, coal, gas, before they are delivered to the process and, apart from electricity, during their combustion. BRE has calculated the emission factors for these fuels per MJ of delivered energy. These are given in Annex 3. Combustion emissions from fuels are calculated using UK emission rates supplied by NATCEN. Where factory chimney emissions of specific gases are supplied, they are compared with the theoretical combustion emission values from the relevant fuels and substituted, with substantiation required for any discrepancies in the values. This process allows manufacturers using techniques that minimise emissions, such as SO 2 to benefit from their improved performance. Upstream emissions from the extraction, processing and distribution of fuels have been calculated from DUKES6 and the UK Greenhouse Gas Emissions Inventory7. Where factory chimney emissions of specific gases have been supplied and substituted for theoretical combustion emissions (see section 4.4), the upstream emissions will still be added to the Profile. Feedstock energy Feedstock energy is defined by ISO8as ‘the combustion heat of raw material inputs, which are not used as an energy source’. BRE includes the feedstock energy of fossil fuels in its primary energy calculations but does not include feedstock energy of non-economic fuels, e.g. timber. Tillman9 has discussed the problems of accounting for inherent and feedstock energy to avoid double counting. Embodied energy and embodied carbon dioxide There is no definition for embodied energy in the ISO Standards. The generally accepted definition is that produced by International Federation of Institutes of Advanced Studies (IFIAS) at a summer school on energy analysis in 1974: ‘the total primary energy that has to be sequestered from a stock within the earth in order to produce a product or service’ 10. The energy used in the extraction and processing of a material is sometimes defined as its initial embodied energy to distinguish it from the energy used at other stages in the material life cycle. Although values for initial embodied energy may be calculated on a mass basis as part of the unit process data, like other effects they must only be used within a system to make comparisons of alternative functional units, i.e. designs of particular components, elements or whole buildings with the same function. Once an element or building has been defined, then the whole life of the materials and products can be included in the embodied energy value - the energy used to extract, transport and process raw materials, to convert them into manufactured products and components, to transport them to the construction site and incorporate them into a building. The definition in this methodology to be used for the embodied energy of a material over the life of a building is: The total primary energy that has to be sequestered from a stock within the earth in order to produce, transport, maintain and dispose of the materials within a specified product, component, element or building. Many government initiatives are in place to reduce the energy use and CO2 emissions of industry. Carbon dioxide, or "embodied carbon dioxide" data needs to be considered as separate value because, although a major proportion is the result of the use of fuels of all

24

kinds, some processes in building material production release CO2 from carbonaceous materials. Calculation of values The definition of ‘stock within the earth’ requires interpretation in order to determine which input data should be aggregated to calculate a single value for embodied energy. The interpretation adopted by IFIAS when concerns were first raised about the use of fossil fuels required that only non-renewable hydrocarbons (and then confined to those which are extracted as economic fuels) are included in the estimate. Fuel and energy use is converted from delivered to primary terms and then only the energy obtained from fossil fuels, and not that produced from renewable sources, is included in the aggregated estimate. The term ‘embodied energy’ is effectively an accounting analysis and in no way refers to the physical or chemical composition of the materials, and is not meant to imply that there is an inherent energy content that can be recovered. In the calculation of embodied energy or fossil fuel depletion, the energy of feedstocks is not included in the calculation apart from that obtained from fossil hydrocarbons which are extracted as economic fuels e.g. oils. This view is shared by the authors of the guidelines for the Athena project11,12. The impacts of the use of organic materials as feedstock are addressed within the inventory. In this methodology, primary energy will be evaluated as the sum of: 1. the gross calorific value of economic fuels extracted from reservoirs within the UK or imported in crude form into the UK 2. the thermal energy generated in nuclear power stations calculated as the gross electricity generated divided by the average thermal efficiency of nuclear stations 3. refined fuels and electricity imported into the UK, counted as having the same embodied energy per unit of fuel as those generated from primary stocks within the UK. Non economic fuels Fuels defined as non economic fuels do not contribute to fossil fuel depletion. However, they do contribute to the emission of CO2 and other combustion products. Precise emission factors for all fuels should be obtained and added to an Environmental Profile. Where this is not possible, emission data from a similar material should be used. Renewable fuels are considered to be CO2 neutral where the emission of CO2 occurs less than 100 years from the sequestration of the CO2. See section 4.5 below. CO2 emissions from non-renewable fuels used in processing and transporting renewables are included where appropriate. 6.5

Carbon cycle

Carbon sequestration is considered over a timescale of 100 years (as are the impacts of CO2 emissions in relation to their global warming potential). CO2 emissions arising from Carbon sequestered after this date will not be considered, nor the carbon sequestration associated with the emission. One common factor for timber-based fuels (wood, bark, chips, sawdust, shavings etc) is that the CO2 released when they are burnt has been absorbed (sequestered) from the atmosphere and stored in the tree during growth. Had it not been released when the wood was used for energy production, it would have been released during the biological breakdown of the wood that would have taken place instead. The CO2 emissions from timber that is burnt are therefore assumed to be zero, since the use of wood as fuel does not

25

contribute to the build up of CO2 in the atmosphere. For forestry, account is taken of the emissions of methane arising from pruning, trimming, site clearance and felling. Where site clearance involves the release of CO2 from, e.g. peat bogs, sequestered more than 100 years ago, this is also considered. Timber cannot be assumed to be CO2 neutral according to the assumption above because not all timber is burnt at the end of its life. Based on current BRE statistics, BRE assumes that 80% of timber from buildings goes to landfill, whilst 15% is reclaimed and 5% is incinerated. Of the timber that goes to landfill, it may be estimated from Municipal waste figures 13 that half of the timber decomposes over one hundred years and the other half remains inert. Of the decomposed timber, it is assumed methane and carbon will be produced in roughly equal quantities, with some of the methane being burnt and converted to CO2. 6.6

Adjusting carbon dioxide emissions for re-carbonation.

In the case of cement and lime, CO2 will be "carbonised" back into the mortar/cement after manufacture. Again, this carbonation is considered over a 100 year timescale for the product as constructed. Lime carbonation is counted within the per tonne product data because the assimilation of CO2 is a function of how the product behaves and happens in a short timescale. The factor for carbonation will therefore be used at 100%, i.e. 0.785 t/tonne, considered as a property of one tonne of lime at the factory gate. Further explanation is provided in Annex 7 For blocks, whilst the rate of carbonation is slower than for free lime, the rate of carbonation is sufficiently fast for it to be assumed that carbonation will also take place at 100% for the amount of free lime in one tonne of product and 65% of the cement content at the factory gate. For cement, carbonation is an unwelcome activity and one which happens slowly over the life of the building. In this methodology, carbonation will only be considered for the whole building element, because carbonation is greatest for the first 5 cm of concrete exposed to the atmosphere. Thus the carbonation will be calculated for 5cm depth multiplied by the surface area exposed for each concrete element over 60 years. Further explanation is provided in Annex 7 6.7

Emissions

Emissions to air Data for emissions to air derived from fuel use are based on the NATCEN conversion factors provided in Annex 3. These are added to emission figures from the process. Emissions to air are converted to kg of emission per tonne of product produced and presented individually. As much detail is retained as possible. For example, if emissions are known for "formaldehyde" and "VOCs" from a process, this is how they should be entered, even though formaldehyde is a VOC. Emissions to land Emissions to land are the solid wastes derived from the process. These are currently measured only in terms of the tonnes of waste produced and greenhouse gases emitted from landfill and incineration. This position will be revised following further examination into the impacts associated with the disposal of different materials in landfill and incinerators.

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Waste may currently be entered onto the inventory Profiles as a detailed description of the quantities of different waste types emitted. Emissions to water Data on emissions to water requested on the questionnaire receive no further manipulation for the creation of the Profile. Data is entered onto the inventory Profile according to the detail provided in the questionnaire. For the characterised Profile, data is incorporated into the eutrophication and ecotoxicity to water categories. 6.8

Imports

The inputs and outputs attributed to imports of materials and products should, wherever possible, be based upon analyses appropriate to the country of origin and will include the energy of transportation. Where data for the country of origin are not available, the input and output data should be based upon the closest domestically produced product with an addition made for the transportation from the country of origin. The exception to this is for imported refined fuels and electricity; these are attributed the same environmental burdens as those generated from primary sources within the UK. Delivered energy values (in GJ/tonne) represent the calorific value for the gross delivered energy of the appropriate fuel. Gross calorific values include the quantity of heat necessary to evaporate water present in the fuel during the combustion process. This is also termed the higher heating value (HHV). The UK energy statistics on which BRE bases its calculations are presented gross whereas international statistics are presented net or in terms of the lower heating value; if these values are used they will be adjusted using the conversion factors given in Annex 5.

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7 7.1

IMPACT ASSESSMENT Presentation of results: the Environmental Profiles

Environmental Profile of inventory data The standard format for this Profile is shown in Annex 13. It may be applied to per tonne, installed elements and sixty year life elements. This is the data that has been treated according to the inventory data handling procedure in chapters 5 and 6. No further impact assessment is carried out. Inventory Profiles are useful to see, transparently, the data that relates to the production of a product or building element. They are not very useful for understanding the environmental consequences of the product or element because no information is provided on how the inputs and emissions relate to environmental impacts. Environmental Profile of characterised and normalised impact data. The standard format for this Profile is shown in Annex 14. Characterisation and normalisation are important steps towards increasing the understanding of the impacts from a product or element. They allow the user to see the contribution towards each impact category and relate this to the impacts of a person over one year. This stops short of a final evaluation of the importance of each of the different impact categories, where weighting factors would be applied. 7.2

The impact assessment process

All units of measurement must be recognised as proxies for both the activity that causes the impacts and for the effects of an impact. In assessing environmental impacts, parameters interact and there is no point at which cause starts and effects finish. Every effect becomes the cause of additional impacts. Hence, the aim is to comprehensively account for all of the burdens and impacts arising but avoid omissions or double counting. Many different impact assessment methodologies have been developed and are available for use. Much of the BRE methodology is based upon the work of Heijungs et al at CML, the University of Leiden in the Netherlands. This team have a significant input to the work of the Society for Ecological Toxicology and Chemistry (SETAC), a leading authority in life cycle analysis development. The three stages of impact assessment, classification, characterisation and normalisation, have been undertaken, as follows: Classification Classification is the process of allocating different environmental burdens (interventions) to categories of impact. BRE propose to follow international practice in the classification of inventory data into impact categories. Data in the UK national database will be classified for its impacts on the environment according to the following scheme: Climate change Acid deposition Ozone depletion Pollution to air: Human toxicity Pollution to air: Low level ozone depletion Fossil fuel depletion and extraction Pollution to water: Human toxicity

Pollution to water: Ecotoxicity Pollution to water: Eutrophication Minerals extraction Water extraction Waste disposal Transport pollution and congestion: Freight

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Characterisation Characterisation is the process of defining the contribution of an environmental burden (intervention) to a particular category of impact. For each category, there may be one burden which makes a contribution which is considered to have a contribution to that impact, or 'potency', of 1. Other burdens are provided with a potency factor relative to this. Alternatively, the burden can be characterised by measuring it in a particular unit, such as tonnes of oil equivalent (toe). BRE propose to follow international practice in the characterisation of inventory data for their potency within the different impact categories. Annex 11 shows the methods to be adopted to characterise data from the UK national database for the potency of impacts on the environment. Work is continuing internationally to develop improved methods of characterisation methods and BRE will continue to adapt to appropriate international practice. Areas of particular weakness that have been identified are human toxicity, ecotoxicity and ecological diversity. Normalisation In common with many other groups internationally, BRE will use normalisation of impacts against the impacts arising from human activity. Normalisation entails comparing the impacts arising from any activity (e.g. production of a tonne of material, production of a kWh of electricity, providing laundry services for a hospital for a year) with those from a common unit of activity – usually the impacts for an average citizen for a year. This step reduces each impact to a dimensionless ratio and eliminates the problem of units being widely variant between issues (e.g. kgCO2, tonnes of mineral extracted). Normalisation will be based on impacts from an average UK citizen, calculated by taking data on UK emissions, energy use etc, applying characterisation factors, and dividing by the population. A table of the characterisation and normalisation factors used is provided in Annex 11. The first set of sheets headed “Characterisation Factors” shows the parameters and values used to assess the relative potency of the different emissions and consumption in terms of the selected proxy measurement unit. The headings show the different issues addressed. The second set of sheets headed “Normalisation Factors” shows how the total UK emissions/consumption divided by the UK population gives the total UK impact per person. These factors are then characterised to give the characterised impact for each impact per person. The normalised impact is the characterised impact contributed by a material expressed as a percentage of the characterised impact contributed by a UK citizen in one year. 7.3 Explanation of impacts on the characterised and normalised Profile Each of the categories in the characterised and normalised Profile is described below. Climate change tonnes CO 2 eq. "Global warming" is associated with problems of increased desertification, rising sea levels, climatic disturbance and spread in disease. It has been the subject of major international activity, and methods for measuring it have been presented by the Intergovernmental Panel on Climate Change (IPCC). Gases recognised as having a "greenhouse" or radiative forcing effect include CFCs, HFCs, N2O and methane. Their relative global warming potential (GWP) has been calculated by comparing their direct and indirect radiative forcing to the emission of the same mass of CO2

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after 100 years. E.g. CFC-11 is 3400 times more powerful as a greenhouse gas than CO2 and therefore one tonne of CFC-11 is equivalent to 3400 tonnes CO2. Global warming potential is measured in CO2 equivalents for each emission, which can be added and entered into the Profile under “Climate change” as CO2 equivalents (100yrs). A timescale is applied to the GWP figure because the GWP of different gases is related to the amount of time they will spend in the atmosphere and the amount of radiative forcing they will induce over that period. It is important to recognise how long the gases will last in the atmosphere. For example, both carbon dioxide and CFC-11 are greenhouse gases but they have different half lives in the atmosphere and they will thus have a different relative effect over different timescales. Three different scenarios are available for GWP: 20 years, 100 years and 500 years. The 100 year scenario is most commonly used and has been applied here. Fossil fuel depletion toe This unit reflects the total quantity of fossil fuel energy depleted by consumption. It is measured in tonnes of oil equivalents - (toes), which is a unit of energy. The characterisation method assumes that the energy content of all fossil fuels is equally valuable to total fossil fuel resources. This is measured from the perspective of their depletion with a characterisation factor of 1 per tonne of oil equivalent for all fossil fuels. The characterisation factor for all fossil fuels will then be the primary energy value of the fuel in toe. Acid deposition Kg SO2 eq. Acid deposition on landscapes causes ecosystem impairment of varying degree, depending upon the nature of the landscape ecosystems. Gases are related to the acidification of one tonne of Sulphur Dioxide (SO2). They include Ammonia, Hydrochloric acid, Hydrogen Fluoride, Nitrous Oxides and Sulphur Oxides. The equivalents are calculated by dividing the contribution of protons (H+) to the ecosystem from a compound with the contribution from SO2. Ozone depletion Kg CFC11 eq. Ozone depleting gases cause damage to statospheric ozone or the "ozone layer". There is great uncertainty about the combined effects of different gases in the stratosphere and all chlorinated and brominated compounds that are stable enough to reach the stratosphere can have an effect. CFC manufacture is banned after 2000 and HCFCs will be phased out by 2015. In the characterisation method, gases are related to the ozone depletion potential (ODP) of one kilogram CFC-11. Human toxic air pollution Human toxic water pollution Ecotoxic water pollution

Kg. tox

The subject of toxicity is a particularly complex area within impact assessment and a variety of different techniques have been developed. The four categories proposed by Heijungs (1992) at the University of Leiden for the CML method is the most widely accepted method and BRE therefore advocate the use of this technique in the absence of more definitive works. CML developed a provisional method of toxicological weighting factors. For human toxicity these are then calculated as (human toxicological classification factor) x (kg body weight/kg substance). The factors are based on tolerable concentrations in air, air quality guidelines, tolerable daily intakes and acceptable daily intake.

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BRE are paying close attention to developments in the field and are particularly interested in the work of the World Health Organisation to develop Disability Adjusted Life years (DALYs) and Percentage Affected Fractions (PAFs) for human and eco-toxic effects respectively. Low level ozone creation kg ethene eq. In atmospheres containing nitrogen oxides, ozone creation occurs under the influence of radiation from the sun. Different hydrocarbons react to form ozone at different rates and both NOx and volatile organic compounds (VOCs) can control the rate of this photo-oxidation process. Increased ozone in the lower part of the atmosphere is important at a local, regional and global scale but impact assessment methods concentrate on the local and regional impacts. The formation of ozone and other oxidants, such as nitrogen dioxide, hydrogen peroxide and aldehydes, are implicated in impacts as diverse as crop damage and increased incidence of asthma and other respiratory complaints. The method used for characterisation in the Profile comes from CML and compares the photochemical ozone creation potential of VOCs to that of ethene. Eutrophication KgPO4 Phosphate is the unit against which a number of emissions to air and water are measured for their equivalent eutrophication or “nutrification” potential, leading to loss of biodiversity through over-enrichment of water supplies. Species dependent on low-nutrient environments are lost and algal blooms occur in water, increasing mortality of aquatic fauna and flora. Ammonia, Nitrates, Nitrous Oxides and total Nitrogen and Phosphorous are included within this part of the Profile. This characterisation factor is derived from the Dutch CML method. Minerals extraction tonnes This unit was selected to reflect the total quantity of mineral resource extracted. This applies to all minerals, including metal ore, and applies to both UK and overseas extraction. The extraction of minerals for building in the UK is a high Profile environmental topic but the minerals themselves are not considered to be scarce. It would be useful to develop a method that includes reference to scarcity. This unit is not currently used to make such a distinction. The assumption is that this unit is a proxy for levels of local environmental impact from mineral extraction. The characterisation method assumes that all mineral extractions are equally disruptive of the local environment and a characterisation factor of 1 is used per tonne of material extracted. Water extraction litres This unit was selected to reflect the depletion, disruption or pollution of aquifers or disruption or pollution of rivers and their ecosystems due to over abstraction. The characterisation factor is 1 per cubic metre and assumes that all abstractions are equally damaging. This is a significant area of impact which warrants further research. Waste disposal tonnes At the present time, it is most practical to use a tonne of waste as a proxy for the impacts arising from waste disposal. This unit was selected to reflect the depletion of landfill capacity, the noise, dust and odour from landfill (and other disposal) sites, the gaseous emissions and leachate pollution from incineration and landfill, the loss of resources from economic use and risk of underground fires etc. The characterisation factor is 1 assuming that 1 tonne of any waste is equally deleterious. In practice, wastes will vary in their putrescible content, combustibility, leachability of toxic substances etc. The exception to the "proxy" status of the associated impacts is for greenhouse gases. The greenhouse emissions from landfill and incineration are included in the sixty year life element Profile. This category is likely to be replaced by information on the per tonne impacts of waste disposal in the UK, which is a mix of incineration and landfill.

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Transport pollution & congestion tonne.km This unit was chosen to reflect the impacts arising from the transport of freight world wide, including ocean travel. It is particularly useful because it provides a figure for an impact over which producers have direct control. Tonne.km reflect the local transport pollution, congestion, noise, dust and discomfort to travellers and to those local to transport routes especially roads. The characterisation factors used is 1, implying that all modes of tonne.km are equally damaging. This characterisation factor will be the subject of future refinement. It is recognised that transport associated with the production and construction of buildings is also converted to emissions to atmosphere from the combustion of the fuel used and Primary energy figures reflect the production of the fuel itself. Tonnes km is not displayed to reflect these impacts, which are accurately accounted for within the other categories and therefore does not produce a double counting effect.

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8

REFERENCES

1. SETAC, 1993. Guidelines for Life-Cycle Assessment: A 'Code of Practice'. Society of Environmental Toxicology and Chemistry, Brussels. 2. Edwards S, 1998. A Survey of Life Cycle information ENP98/7 Unpublished Client Report. 3. Connaughton J, Life Cycle Energy Costing, Building Services, October 1990 pp 34-36, in Environmental Research Group, Building Materials in the Context of Sustainable Development, Life Cycle Energy Use in Building Materials, Forintek Canada Corp., August 1994. 4. National Waste Classification Codes and Hazard Property Codes. EPA 1990 Special Waste Regulations. September 1996 5. UK Transport Statistics 6. DUKES, 1997. Digest of UK Energy Statistics, 1997. Department of Trade and Industry. 7. Salway A G, 1995. UK Greenhouse Gas Emission Inventory, 1990 to 1993. AEA Technology. 8. ISO, 1997. Environmental Management - Life cycle assessment - Principles and framework. BS EN ISO 14040 : 1997. Environmental management - Life cycle assessment - Goal and Scope Definition and Inventory Analysis International Standard ISO 14041. 9. Tillman A M, 1995. Energy in Life Cycle Assessment. In: Environmental data for building materials in the Nordic countries. TemaNord 1995:577 Nordic Council of Ministers. 10. Chapman P F and Roberts F, 1983. Metal resources and energy. Butterworths. 11. Athena, 1993 Building materials in the context of sustainable development: research guidelines. Annex in Phase III Summary Report. Forintek Canada Corporation and Wayne B Trusty Associates Ltd. 12. Athena, 1997 Research Guidelines. January 1997 revision. Athena Sustainable Materials Institute. 13. Royal Commission for Environment 1993 17th Report. HMSO, London. 14. SPOLD, 1997. (Society for Promotion of Life Cycle Development) Common Format for LCI data. Av. E. Mounier 83, Box 1, B-1200 Brussels.

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9

ANNEXES

A1 AVERAGE GROSS CALORIFIC VALUES FOR UK FUELS - 1996

coal:

coke coke breeze other solid industrial wood straw chicken litter refuse derived waste tyres petroleum products:

average UK power station iron and steel other industry house coal Anthracite

average UK LPG motor spirit burning oil gas/diesel oil fuel oil power station oil orimulsion

natural gas coke oven gas blast furnace gas landfill gas sewage gas Source: DUKES, 1997 A2 FUEL USED IN ELECTRICITY GENERATION 1996 Coal Oil Gas Nuclear Onshore Wind Small Scale Hydro Large scale Hydro Landfill Gas Sewage Sludge Digestion Municipal Solid Waste Combustion Other Biofuels Other Fuels (eg Coke oven gas, blast furnace gas etc) Net Imports Source: Based on DUKES 1997

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GJ/per tonne 26.4 25.0 31.3 28.6 30.6 33.9 28.1 24.8 27.9 11.9 15.0 9.9 18.7 32.0 45.9 49.6 47.4 46.5 45.8 42.7 42.7 29.8 MJ per cubic metre 39.1 31.3 42.2 38.6 38.6

42.17% 4.47% 21.05% 28.39% 0.05% 0.01% 0.36% 0.29% 0.17% 0.51% 0.17% 0.52% 1.85%

A3 TOTAL AND UPSTREAM FUEL EMISSION FACTORS 1996 Figures from NETCEN National Atmospheric Emissions Inventory: UK emissions of Air pollutants 1970-1996. (published January 1999). TOTAL UPSTREAM AND COMBUSTION EMISSIONS FACTORS grams/MJ Burning Oil Gas Oil Fuel Oil Coal Coke and Coke Breeze Coal (Cement & Lime) LPG Natural Gas Biogas Petrol Waste Oil Rail Freight Gas Oil Coastal Shipping Containerised Shipping Coke Oven Gas Brick additives Road Transport (HGV)

CO2 75.83 76.70 81.08 85.17 117.25 76.90 67.81 53.88 0.00 74.23 78.74 76.70 76.70 76.70 69.03 110.52 76.70

CH4 0.021 0.021 0.023 0.261 0.336 0.253 0.019 0.112 0.615 0.021 0.001 0.024 0.023 0.027 0.334 0.173 0.027

N20 0.00060 0.00059 0.00060 0.00747 0.00005 0.00343 0.00009 0.00010 0.00000 0.00003 0.00000 0.02623 0.00439 0.00439 0.00005 0.00002 0.02063

NOx 0.076 0.091 0.192 0.164 0.176 0.431 0.092 0.093 0.897 0.088 0.535 0.780 1.544 1.260 0.086 0.173 1.003

CO NMVOC 0.0099 0.0702 0.0117 0.0702 0.0182 0.0712 0.1440 0.0181 0.1485 0.0319 0.0902 0.0163 0.0069 0.0656 0.0027 0.0090 0.1649 0.0473 0.0116 0.0702 0.0843 0.0031 0.4279 0.3544 0.2248 0.2408 0.1681 0.1144 0.0049 0.0305 0.1472 0.0255 0.5633 0.2802

SO2 PM10 0.059 0.0018 0.107 0.0070 1.051 0.0257 0.791 0.0875 0.717 0.0105 0.380 0.0790 0.014 0.0030 0.002 0.0011 0.000 0.0058 0.048 0.0058 0.590 0.0000 0.107 0.0070 0.469 0.0249 0.469 0.0249 0.431 0.0016 0.697 0.0104 0.107 0.0954

UPSTREAM FUEL EMISSION FACTORS grams/MJ CO2 CH4 0.6095 0.2517 Coal 13.46 0.3265 Coke 150.4 0.4043 Electricity (all producers) 1.718 0.1083 Gas 2.685 0.0184 Natural Gas Liquids as Products 8.159 0.0206 Non Energy Petroleum Products 8.093 0.0204 Oil and Petroleum Products

N2O

NOx

CO

NMVOC SO2

PM10

0.000021 0.001661 0.000627 0.000069 0.004634 0.000128 0.000046 0.005336 0.002548

0.01292

0.005577

0.01752

0.4218

0.1665

0.0411 0.000274 1.234

0.03284

0.000011 0.003187 0.000314 0.005412

0.00183 0.000079

0.000003

0.00335

0.0045

0.06372

0.01444 0.000211

0.000026

0.01545 0.006558

0.0689

0.04626 0.001222

0.000026

0.01533 0.006505

0.06835

0.04589 0.001546

A4 PRIMARY ENERGY RATIOS FOR UK DELIVERED ENERGY - 1996 Fuel Natural Gas Petroleum Products Coal Coke, Coke Breeze and Coke Oven Gas UK Electricity

Primary:delivered 1.110 1.110 1.013 1.316 3.083

Source: Based on DUKES 1997 and UK Greenhouse Gas Emissions Inventory 1996

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A5 GROSS v NET CALORIFIC VALUES Gross calorific values include the quantity of heat necessary to evaporate water present in the fuel during the combustion process. Net values do not. UK energy statistics are presented gross, whereas international statistics are presented net. If conversion is required, the following approximate adjustments should be made. Gross to Net -5% -10%

solid and liquid fuels (including wood) gases Source: DUKES, 1997 A6 STANDARD CONVERSION FACTORS AND UNITS

There are a number of units of energy used for collecting and publishing data. To convert from one to the other, the following table should be used. To convert from the units on the left hand side to the units across the top, multiply by the values in the table. FROM MJ GJ KWh therm BTU Kcal Tonnes oil equiv.

TO MJ

GJ

kWh

therm

BTU

kcal

1 1000 3.6 105 1.05E-03 4.187E-03 41868

0.001 1 0.0036 0.10551 1.0551E-06 4.187E-06 41.868

0.277 277.78 1 29.31 2.931E-04 0.001163 11630

0.009 9.4781 0.034121 1 1.00E-05 3.97E-05 396.8

947.81 947,810 3,412 100000 1 3.968 39,682,909

238.846 238,846 859.8 25,200 0.2520 1 10,000,000

The standard units required for data presentation are: Energy: MegaJoules (MJ) Input materials and output materials: Tonnes (t) Emissions to land: Kilogrammes (Kg) Emissions to air: grammes (g) Emissions to water: milligrammes (mg)

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Tonnes oil equiv. 0.0000239 0.0239 8.598E-05 0.00252 2.52E-08 1.00E-07 1

A7 CARBONATION CALCULATIONS This annex sets out how the carbonation of materials is accounted for within the Environmental Profiles methodology. The method set out here represents a first attempt to incorporate the effects of carbonation into the life cycle of building materials and is likely to be refined as understanding of this issue increases. First principles The amount of CO2 reacting with 1 tonne of pure CaO is 0.785 tonnes. This figure is derived from the molecular mass of carbon dioxide divided by the molecular mass of calcium oxide. Equation 1: 44/56.08 = 0.785 tonnes This assumes CaO + CO 2 → CaCO 3 The calcium content of Portland cement, expressed in terms of CaO, is typically about 65%. This will mainly be in the form of calcium silicates with some calcium aluminate and free lime as well as minor phases such as ferrite and gehlenite. The main products of cement hydration are calcium hydroxide and calcium silicate hydrates, together with small amounts of calcium aluminate hydrates, calcium sulfoaluminate hydrates etc. All of these are prone to carbonation and ultimately most of the CaO can be converted to CaCO3. The potential amount of CO2 absorbed will therefore depend mainly on the amount of free lime and the cement content (and its CaO content). Pfa and ggbs may increase the rate of CO2 absorption although its contribution is likely to be small. Pfa and ggbs will react with the cement, reducing the amount of Ca(OH) 2 present. However, again the products will eventually carbonate. Ggbs and pfa may reduce slightly the amount of CO2 absorbed but not to a significant extent within the accuracy of carbonation estimates. The amount of CO2 absorbed can therefore be estimated from: Equation 2 ((amount of free lime) + (cement content x 0.65)) x 44/56 Lime mortars carbonate over a period of months. Concrete can take decades to carbonate. However, aerated concrete blocks are likely to carbonate comparatively quickly. The actual amount that carbonates will depend on the environment - particularly the relative humidity (RH) -and the lifetime of the material. If the RH is low then carbonation will be very slow. If the material is fully saturated carbonation will also be slow as CO2 cannot penetrate into the material. For concrete the maximum rate of carbonation occurs in the RH range 50 - 90%. Chemical reaction may reduce the rate of carbonation but will not have a major effect on the ultimate amount of carbon dioxide absorbed. The amount of CO2 absorbed by Lime can be estimated from: ((amount of free lime) x 44/56 = tonnes of CO2 absorbed per tonne of Lime The amount of CO2 absorbed by Precast Concrete Blocks can be estimated from: ((amount of free lime) + (cement content x 0.65)) x 44/56 = tonnes of CO2 absorbed per tonne of Precast Concrete Block The amount of CO2 absorbed by concrete can be estimated from: (cement content x 0.65)) x 44/56 = tonnes of CO2 absorbed per tonne of Concrete The amount of CO2 absorbed in a concrete element can be estimated from: (Assume 5cm depth absorption): (cement content x 0.65)) x 44/56) x 5cm x surface area exposed.

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A8 TRANSPORT METHODOLOGY FOR CALCULATING FUEL USE. Road The assumptions to be used for Road Transport are listed below A Annual Delivery Quantity This is taken to be the annual input quantity of the product into the process, even where more or less product has been delivered in the given period than has been used, due to stockpiling, or no quantity is given Transport is considered for all given inputs into the process, including fuels such as diesel and LPG. B Gross Laden Weight of Vehicle Where data is given on the size of vehicle, it is taken to mean the GLW of the vehicle. The maximum size of vehicle permitted on UK roads until 1999 was 38 tonnes, except for travel to or from a railhead. Therefore, unless details of rail transport are also given, the maximum size of vehicle is assumed to be 38 tonnes. C Average Delivery Load Where the average delivery load is not given, then it is calculated from DETR UK Transport Statistics for the Gross Laden Weight of the Vehicle as given and for the type of load it is carrying figure (taking account of part load % if necessary). If neither an Average Delivery Load nor a Gross Laden Weight of Vehicle are given, then the Annual No of Deliveries is used to calculate the Average Delivery Load. The Gross Laden Weight is then estimated from this. If no Annual No of Deliveries is given either, then the most common form of transport for that commodity is taken from UK Transport Statistics3. D Annual No of Deliveries Where this information is given, it is used to calculate the Average Delivery Load (A/D). Where either the Gross Laden Weight of the Vehicle or Average Delivery Load have also been given, then it is checked that the calculated average load agrees with the given average load. If it is not given, then it is calculated (A/C). E Delivery Distance If this is not given, then it is taken as the “average haul” from the UK Transport Statistics for the given vehicle type and commodity transported. F Full or Part Load Where the delivery is a full load, e.g this is the only delivery made on the outward trip, then the load is 100%. Where the delivery is a part load, we have presented the information as the percentage of the load taken by the given delivery. If no percentage has been given, then it has been assumed to be 25%. For a part load, the fuel consumption is calculated in exactly the same way as for a full load, but only the given percentage is allocated to the product. G Return Trip Empty or Full Where no data has been given, the return trip has been assumed to be Empty. For Empty trips, then the delivery distance is doubled to give the total distance travelled per delivery. Part Loads are taken to be Empty Returns. For Full trips, then the delivery distance is taken to be the total distance travelled per delivery. H Total Distance Travelled If the Return Trip is Full then Total Distance Travelled = Delivery Distance (E). If the Return Trip is Empty or the delivery is Part Load, then Total Distance Travelled = 2* Delivery Distance (2E). J Fuel Consumption Taken from DETR UK Fuel Statistics for each class of vehicle (B), and converted to litres/km.

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Fuel Used = No of Deliveries * Distance Travelled * Part Load % * Fuel Consumption = D * H*F*J Fuel Consumption Figures: 1997 DETR Correspondence Rigid Rigid Rigid Rigid Rigid Artic Artic Artic <7.5t 7.5-14t 14-17t 17-25t 25t+ <=30 t 30-33t 33 t Miles Per 11.8 10.7 8.9 6.8 6.5 7.9 7.9 7.2 Gallon Kilometres Per 19.0 17.2 14.3 10.9 10.5 12.7 12.7 11.6 Gallon Litres Per 0.2394 0.2641 0.3175 0.4155 0.4347 0.3576 0.3576 0.3924 Kilometre Rail The various types of information which have been provided for Rail Transport are listed below: A Annual Delivery Quantity: This is taken to be the annual input quantity of the product into the process, even where more or less product has been delivered in the given period than has been used, due to stockpiling. B Type of Rail Transport This is taken to be a Western European mix of Electric and Diesel. All rail travel is assumed to be containerised. E Delivery distance A Delivery Distance must be obtained for rail transport. J Fuel Consumption 0.15MJ/t.km electricity 0.1466MJ/t.km Diesel Train Electricity consumption = A x Ex J (0.15) Train Diesel consumption = A x Ex J (0.1466) Both of the above calculations should be carried out for each train journey

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Shipping The various types of information which have been provided for shipping are listed below: A Annual Delivery Quantity: This is taken to be the annual input quantity of the product into the process, even where more or less product has been delivered in the given period than has been used, due to stockpiling, or no quantity is given B Type of Ship Where data is given on the type of ship, fuel consumption data for that type of shipping will be used. Otherwise it is assumed that containerised shipping is used and this fuel consumption will be used. C Average Delivery Load Where the average delivery load is not given, then it is assumed that it is equal to the Annual Delivery Quantity (A). D Annual No of Deliveries Where this information is given specifically for shipping, it has been used to calculate the Average Delivery Load (A/D). Otherwise it is assumed to be 1. E Delivery distance A Delivery Distance must be obtained for shipping transport. G Return Trip Empty or Full Where the return trip is given as empty, then the distance travelled is taken to be double the delivery distance. Otherwise, shipping is assumed to be containerised with a full return trip. J Fuel Consumption Tonne-km fuel consumption has been used of 0.0038 kg Diesel/ tonne-km for Containerised Shipping and 0.0018 kg Diesel/tonne-km for Inland Navigation. Fuel Consumption = Annual Delivery Quantity * Delivery Distance * Annual Number of Deliveries * Fuel Consumption = A * E * D * J

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A9

SOURCES OF LCA DATA

The primary sources of supplementary upstream life cycle inventory (LCI) data used in the project are: 1.

SimaPro Pre Consultants B.V Plotterweg 12 3821 BB Amersfoort The Netherlands www.pre.nl The SimaPro tool contains data from: Pre 4 Database, collected by Pre BUWAL 250 Database, developed by EMPA St. Gallen in Switzerland for Swiss Ministry of the Environment (BUWAL). IDEMAT database developed by Delft University of Technology. Franklin USA LCI Database.

2.

IVAM LCA Data 2.0 The IVAM Environmental Research LCA database IVAM Environmental Research PO Box 18180 1001 ZB Amsterdam the Netherlands www.ivambv.uva.nl

3

SBI Database Danish Building Institute SBI Produced for the Danish Government and published in 1998. www.sbi.dk

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A10 THE STANDARD QUESTIONNAIRE FOR INVENTORY DATA COLLECTION.

Construction Materials and the Environment ENVIRONMENTAL P ROFILES OF CONSTRUCTION MATERIALS, COMPONENTS AND BUILDINGS QUESTIONNAIRE to be used for the collection of data from : a) b) c)

raw material processing (including transport to factory) or secondary processing (including transport to factory) or component manufacture (including transport to factory)

This data will be used to calculate figures of inputs and outputs associated with the production of one tonne of your products. This questionnaire requests the raw data that will allow these calculations to be made. An electronic version of this document is available. You may wish to customise this questionnaire for your industry 1.

PROCESS AND PRODUCTS

This questionnaire requires information about the process described on the accompanying PROCESS TREE to produce the following product(s). (Please include BS or CEN numbers, end use, grade, thickness, density, weight etc. in your description of the finished product) ............................................................................................................. .............................................................................................................

Please provide a PROCESS TREE containing information about the main process and sub-processes involved, using the guidance attached. Information will be collected for the overall process but it is important to produce a detailed flow chart to aid the assessment of the data you provide and to ensure that the key processes have been included.

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2.

PLANT INFORMATION

Company name/code number ............................................................................................................. Company address ............................................................................................................. ............................................................................................................. Telephone....................................................... Fax................................................................. Name of respondent…………………………………………………

3.

QUALITY OF DATA

Age Please indicate below the starting and end months and the year(s) in which the data in this questionnaire was collected Start month and year ............................................................................................................. End month and year ............................................................................................................. Please indicate in the questionnaire where the age of specific data differs from that stated above. Source of data Please provide information about the sources and derivation of all figures. Where possible, include data ranges or other descriptions so that it is clear how any general figures were calculated. Please state clearly whether the figures quoted are based on measured or estimated values and the basis for both measurements and estimations .

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4.

WORKS OUTPUT

Please enter all the principle outputs i.e. main products and any co-products of the production site (not including material sent to waste disposal) and the annual production of each. This information allows the burdens of production to be allocated to co-products using physical relationships Output description

Production (000 tonnes)

Approximate value (£/year)1

1We ask about the value for each output (i.e. how much are you paid for each) as an alternative means of allocation, should this be necessary. You do not need to give this information now but in the future we may need to discuss how you can provide it on a confidential basis. 5.

WORKS INPUT

5 a) Materials We are interested in all the inputs to the plant that are associated with your product. Please include packaging materials and consumable items, as well as the ingredients of your product. Please list all input materials even if you know you cannot provide information about their manufacture before they reach you. Examples are: Raw materials: Minerals - limestone, clay, silica, sand, gravel Metallic minerals - zinc, alumina, iron ore Wood materials - solid timber, sawmill chips, other residues (with species where possible) Fossil fuels used as feedstock materials rather than for energy production - natural gas to make plastics, petroleum products to make roofing materials Processed materials: screws, resins, paints scrap and materials recycled from other processes consumable items - sanding paper, drilling bits, detergents, lubricating oils ( Note: this does not include the repair and maintenance of machinery and vehicles) Ancillary materials Data is required for 98% of the materials input by mass. Data is thus also required for all materials with a mass greater than 2% of the output from the process. Please also provide information on materials which, although they contribute less than 2% by mass, may possibly have significant effects in their extraction, their use or disposal, or are highly toxic or classed as hazardous waste. For example, the adhesives which are used in the manufacture of window frames are integral to the product and should be included even though they account for less than 2% of the outputs (by mass).

44

Item

Physical quantities (specify units e.g. dry tonnes)

5 b) Transport of materials to the factory This may be achieved by more than one mode of transport. Please list these and detail the mileage of each mode separately. Where more than one supplier is used you may estimate the tonnage from each and indicate this on the table. The data for each supplier can then be entered into the table. Material (specify)

Quantity to plant/yr (t)

Transport method (eg 40 tonne lorry)

No. deliveries per year.

Average distance source to plant (km)

Return journey: empty/ full/ part load (give %)

What is carried on return?

Please provide any further information about the material inputs .............................................................................................................. ..............................................................................................................

5 c) Direct consumption of fuel Please enter the fuel purchased by your plant for one year. Include all fuels purchased for the site, including fuels used for heating and lighting in buildings. It will be useful to indicate what different fuels are used for. This helps to ensure all are included. Please only include vehicle fuels used for transport on site. Fuel Purchased

What are the fuels used for?

Unit of fuel purchased (eg/ m3 or kWh)

heating oil diesel kerosene gasoline natural gas landfill gas LPG coal biomassspecify grid electricity1 waste from plant (specify)

45

Total quantity used per year

Source of data

Calculate own emissions ()

external waste2 (specify) other (specify) 1 if electricity is not purchased from the national supply, please indicate its source 2 for example, wood residues, secondary liquid fuels (SLF). For these fuels, provide information about transport mode and distances in Table b)

5 d) Water Use Please enter the water brought into the plant in the year. Water Use

Units

quantity used/yr

quantity/tonne of each product

water purchased from water company surface water - private supply groundwater - private supply other

5 e) Capital Equipment Although it is a form of indirect energy input into the process, the contribution of capital equipment is not normally considered in LCA and so it will not be included here. 6.

WORKS EMISSIONS/DISCHARGES

Emissions from a plant may be from more than one product. If you can allocate emissions to specific products, by causal relationship, please attach a description of the method used. If you cannot do this, please give emissions for the whole plant. Please give the units in which your emissions are measured. BRE will convert general fuel data to emissions using standard conversion figures. Please tick the appropriate boxes in Table 5 c) if you wish to provide your own emissions in the table below. Please enter these emissions and the fuel sources beside your data entry in Table 6 a) below.

46

6 a) Emissions to Air Emission to outside air

Measured Quantity per year (include range)

Total emission Volume

Emission concentration

Units measured

Sampling procedure (include baseline)

Own fuel emission calulations from: (state source)

Wherever possible, provide specific data on: carbon monoxide sulphur dioxide nitrogen oxides For the following categories, please list individual compounds wherever possible: particulates (with percentage composition for each component) volatile organic compounds halogens hydrocarbons e.g. methane metals e.g. lead 6 b) Discharge to Water Discharges to water

Total water to sewer Total water to surface water BOD to sewer to surface water COD to sewer to surface water Total organic carbon to sewer to surface water pH to sewer to surface water Suspended solids 1 to sewer to surface water other1 to sewer to surface water

Units

l l

Measured value in discharge (average and range) N/A N/A

mg/l mg/l mg/l

1Please include data on specific compounds e.g. oil and grease metals (specify) cyanide

47

Total volume of discharge

Sampling procedure

N/A N/A

detergents phosphates phenol and phenolic compounds ammonia and ammonium compounds halogenated and non-halogenated organics chlorides heated water 6 c) Solid Waste Please provide a list of the main materials in the description of the wastes produced. For special waste, it would be useful to use the National Waste Classification codes and Hazard Property codes (EPA 1990 Special Waste Regulations September 1996). Waste produced

Description of waste

Quantity per year (t)

Destination e.g. Landfill, incinerator

Controlled: Commercial Controlled: Industrial Controlled: Special

Any further information on the emissions and discharges…………………… Please direct any queries to […………..] Thank you for answering this questionnaire

48

A11

CHARACTERISATION FACTORS

Climate Change Source: IPCC 1995

9.1

Emissions to Air

kg CO2 eq. (100years)/kg C2F6 C3F8 C4F10 C5F12 C6F14 C-C4F8 CCl4 CF4 CFC-11 CFC-113 CFC-114 CFC-115 CFC-12 CFC-13 CH2 Cl2 CH3 CCl3 CH4 CHCl3 CO2 HALON-1211 HALON-1301 HCFC-123 HCFC-124 HCFC-141b HCFC142b HCFC-22 HFC-125 HFC-134 HFC-134a HFC-143 HFC-143a HFC152a HFC-227ea HFC-23 HFC-236fa HFC-245ca HFC-32 HFC-41 HFC-43-10mee N2O SF6

Acid Deposition Source: Heijungs Emissions to Air

9200 7000 7000 7500 7400 8700 -650 6500 2100 3600 7000 7000 7100 13000 9 -320 21 4 1 4900 -86400 50 430 370 1700 1400 2800 1000 1300 300 3800 140 2900 11700 6300 560 650 150 1300 310 23900

kgSO2 eq./kg HCl HF NH3

0.88 1.6 1.88

49

NO NO2 Nox (as NO2 ) SO2 Ozone Depletion Source: Montreal Protocol Emissions to Air

Human Toxicity Source: Heijungs Emissions to Air

1.07 0.7 0.7 1

kgCFC11 eq./kg CCl4 CFC-11 CFC-113 CFC-114 CFC-115 CFC-12 CFC-13 CH3 CCl3 CHCl3 HALON-1201 HALON-1202 HALON-1211 HALON-1301 HCFC-123 HCFC-124 HCFC-141b HCFC142b HCFC-22 Other CFC

1.1 1 0.8 1 0.6 1 1 0.1 0.12 1.4 1.25 3 10 0.006 0.04 0.11 0.065 0.055 1

kg.tox/kg 124trimethylbenzene 22dimethylpropane 2methylhexane 2methylpentane 3methylhexane 3methylpentane 4methylpentan2one Acetone Acetylene Aromatic Hydrocarbons As Ba Benzene But2ene Butan2one Butane Butanols Butylacetate CCl4 Cd CFC-11 CFC-113

50

3.9 0.022 1.6 0.022 1.6 0.022 0.022 0.022 0.022 3.9 4700 1.7 3.9 0.022 0.022 0.022 0.022 0.022 1.9 580 0.022 0.022

CFC-114 CFC-115 CFC-12 CFC-13 CFC-502 CH2 Cl2 CH2 Cl2 CH3 CCl3 CHCl3 Co CO Cr Cu Cypermethrin Dichofluanid Dioxin Ethane Ethanol Ethene Ethylacetate Ethylbenzene Fe Formaldehyde Glycols Glyphosphate HALON-1201 HALON-1202 HALON-1211 HALON-1301 HCFC-123 HCFC-124 HCFC-141b HCFC142b HCFC-22 Heptane Hexane HF HFC-125 HFC-134 HFC-134a HFC-143 HFC-143a HFC152a HFC-227ea HFC-23 HFC-236fa HFC-245ca HFC-32 HFC-41 HFC-43-10mee Hg Isobutane

51

0.022 0.022 0.022 0.022 0.022 0.069 0.069 2.4 1.2 24 0.012 6.7 0.24 0.67 0.11 3300000 0.022 0.022 0.022 0.022 3.9 0.042 0.022 0.0083 0.11 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 1.6 0.022 0.48 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 0.022 120 0.022

Emissions to Water

Isopentane Lindane Malathion Methylheptanes m-ethyltoluene Mn Mo m-xylene NH3 Ni NMVOC NOx (as NO2) Octane Other CFC Other HCFC Other paraffins Other unknown VOC Other VOC o-xylene Paraquat Pb PCB's Pent2ene Pentane Pentane isomers Permethrin p-ethyltoluene Pimiricarb Propan1ol Propan2ol Propane Propylene p-xylene RH Simazine Sn SO2 Tetrachloroethene Toluene Trichloroethene Triflorine V White spirit Xylenes Zn Aliphatic Hydrocarbons Aromatic Hydrocarbons As Atrazine Azinphos-methyl Ba CCl4

52

0.022 0.047 1.7 1.6 3.9 120 3.3 2.2 0.02 470 0.022 0.78 1.6 0.022 0.022 0.022 0.022 0.022 2.2 8.3 160 370 0.022 0.022 0.022 0.67 3.9 1.7 0.022 0.022 0.022 0.022 2.2 0.022 17 0.017 1.2 0.047 0.039 0.061 1.7 120 0.022 2.2 0.033 0.0019 0.66 1.4 0.57 1.1 0.14 0.71

Cd CH2 Cl2 CHCl3 Co Cr Cu Cypermethrin DDT Dichlorvos Dichofluanid Dioxin Drins Endosulfan Ethyl benzene Fe Fenitrothion Fenthion Glyphosphate Hexachlorobenzene Hexachlorobutadiene Hg Lindane Malathion Mo Ni Nitrate Nitrite Orthophosphate Paraquat Parathion Parathion-methyl Pb PCB's Pentachlorophenol Permethrin Pesticides Pimiricarb Simazine Sn Tetrachloroethene Tributyltin Trichlorobenzene Trichloroethane Trichloroethene Trifluralin Triphenyltin Zn Photochemical Ozone Creation Potential Source: Heijungs Emissions to Air

2.9 0.048 0.095 2 0.57 0.02 0.058 0.14 0.71 0.0095 290000 29 0.48 0.021 0.0036 0.57 2.9 0.0095 5.7 2.9 4.7 2.9 0.14 0.29 0.057 0.00078 0.022 0.000041 0.71 0.57 0.14 0.79 32 0.095 0.057 2.9 0.14 1.4 0.0014 0.18 5.7 5.7 0.2 0.2 0.14 5.7 0.0029

kg ethene eq/kg

124trimethylbenzene

53

1.2

22dimethylpropane 2methylhexane 2methylpentane 3methylhexane 3methylpentane 4methylpentan2one Acetone Acetylene Aromatic Hydrocarbons Benzene But2ene Butan2one Butane Butanols Butylacetate CCl4 CFC-11 CFC-113 CFC-114 CFC-115 CFC-12 CFC-13 CFC-502 CH2 Cl2 CH3 CCl3 CH4 CHCl3 Ethane Ethanol Ethene Ethylacetate Ethylbenzene Formaldehyde Glycols HALON-1201 HALON-1202 HALON-1211 HALON-1301 HCFC-123 HCFC-124 HCFC-141b HCFC142b HCFC-22 Heptane Hexane HFC-125 HFC-134 HFC-134a HFC-143 HFC-143a HFC152a HFC-227ea

54

0.398 0.492 0.524 0.492 0.431 0.326 0.178 0.168 0.761 0.189 0.992 0.326 0.41 0.196 0.323 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.007 0.001 0.082 0.268 1 0.218 0.593 0.421 0.196 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.021 0.529 0.421 0.021 0.021 0.021 0.021 0.021 0.021 0.021

HFC-23 HFC-236fa HFC-245ca HFC-32 HFC-41 HFC-43-10mee Isobutane Isopentane Methylheptanes m-ethyltoluene m-xylene NMVOC Octane Other CFC Other HCFC Other paraffins Other unknown VOC Other VOC o-xylene PCB's Pent2ene Pentane Pentane isomers p-ethyltoluene Propan1ol Propan2ol Propane Propylene p-xylene Aliphatic Hydrocarbons Tetrachloroethene Toluene Trichloroethene White spirit Xylenes Eutrophication Source: Heijungs Emissions to Air

Emissions to Water

0.021 0.021 0.021 0.021 0.021 0.021 0.315 0.296 0.469 0.794 0.993 0.416 0.493 0.021 0.021 0.761 0.337 0.337 0.666 0.021 0.93 0.408 0.296 0.725 0.196 0.196 0.42 1.03 0.888 0.398 0.005 0.563 0.066 0.761 0.888

kg.PO4 eq./kg N2O NH3 NO NO2 NOx (as NO2) Ammoniacal N BOD COD Nitrate Orthophosphate Total Nitrogen

Ecotoxicity

55

0.13 0.35 0.2 0.13 0.13 0.33 0.11 0.022 0.1 1 0.42

Source: Heijungs Emissions to Water

Fossil Fuel Depletion Fossil Fuels

3

m /mg Aliphatic Hydrocarbons Aromatic Hydrocarbons As Atrazine Azinphos-ethyl Azinphos-methyl CCl4 Cd CH2 Cl2 CHCl3 Co Cr Cu Cypermethrin DDT Dichlorvos Dioxin Drins Endosulfan Ethyl benzene Fenitrothion Fenthion Hexachlorobenzene Hexachlorobutadiene Hg Lindane Malathion Ni Parathion Parathion-methyl Pb PCB's Pentachlorophenol Permethrin Pesticides Simazine Tetrachloroethene Tributyltin Trichlorobenzene Trichloroethane Trichloroethene Trifluralin Triphenyltin Zn

0.05 0.029 0.2 5 100 100 0.0074 200 0.00094 0.17 1 1 2 250 1.3 2000 1400 53 100 0.023 100 250 53 11 500 2.5 67 0.33 250 8.3 2 100 5.6 710 2.5 1 0.02 250 0.83 0.00028 0.046 5 20 0.38 per toe

Coal Oil Gas

1 1 1

Minerals Extraction

per tonne

56

Minerals Extracted

Stone/rock Clays/earth Sand/gravel Others

Water Extraction Water

1 1 1 1 per litre

Water Co Surface Water Ground Water

Waste Disposal Waste

1 1 1 per tonne

To Landfill To Incineration

Transport Pollution & Congestion

1 1 per tonne.km 1

Freight

1996 Normalisation Factors 1995 figures (in italics) used where 1996 figures not available

Population Nos. UK 58,801,500 GB 57,138,200 England & Wales 52,010,200 Air Pollution

UK Unit CO2 574750 000's t CO 4641 000's t CH4 3712 000's t Nox (as NO2) 2052 000's t NMVOC 2030 000's t SO2 2026 000's t Particulates 356 000's t other unknown VOC 279 000's t other VOC 257 000's t PM10 213 000's t butane 191.51 000's t N2O 189 000's t toluene 136.36 000's t white spirit 98.62 000's t ethanol 98.02 000's t pentane 88.32 000's t propane 76.29 000's t ethene 65.53 000's t isopentane 55.31 000's t isobutane 44.52 000's t hexane 43.43 000's t p-xylene 42.08 000's t benzene 41.33 000's t other parrafins 40.33 000's t m-xylene 39.21 000's t xylenes 35.29 000's t

57

Per UK Citizen 9774.411 kg/person 78.92656 kg/person 63.12764 kg/person 34.89707 kg/person 34.52293 kg/person 34.4549 kg/person 6.054267 kg/person 4.744777 kg/person 4.370637 kg/person 3.622357 kg/person 3.25689 kg/person 3.214204 kg/person 2.318988 kg/person 1.677168 kg/person 1.666964 kg/person 1.502002 kg/person 1.297416 kg/person 1.114427 kg/person 0.940622 kg/person 0.757124 kg/person 0.738587 kg/person 0.715628 kg/person 0.702873 kg/person 0.685867 kg/person 0.66682 kg/person 0.600155 kg/person

o-xylene ethane propylene acetylene trichloroethene heptane formaldehyde methylheptanes 124trimethylbenzen e propan2ol ethylbenzene acetone propan1ol octane CH3CCl3 RH 2methylpentane pentane isomers CH2Cl2 4methylpentan2one butan2one glycols 22dimethylpropane butylacetate ethylacetate but2ene CCl4 tetrachloroethene ArH 3methylpentane butanols 3methylhexane pent2ene m-ethyltoluene p-ethyltoluene 2methylhexane HCFC-22 HCFC-141b HCFC142b CFC-12 Pb Other HCFC CFC-11 CFC-502 CF4 CFC-114 SF6 CFC-113 Other CFC

32.62 000's t 31.33 000's t 30.35 000's t 29.58 000's t 26.23 000's t 26.21 000's t 25.76 000's t 24.79 000's t 23.87 000's t

0.554748 kg/person 0.53281 kg/person 0.516143 kg/person 0.503048 kg/person 0.446077 kg/person 0.445737 kg/person 0.438084 kg/person 0.421588 kg/person 0.405942 kg/person

23.52 000's t 22.62 000's t 22.3 000's t 21.66 000's t 19.73 000's t 19.64 000's t 17.93 000's t 16.32 000's t 15.72 000's t 14.84 000's t 14.16 000's t 14 000's t 11.96 000's t 11.79 000's t 11.55 000's t 11.48 000's t 11.39 000's t 11.32 000's t 10.93 000's t 10.76 000's t 10.49 000's t 9.02 000's t 8.05 000's t 7.82 000's t 7.52 000's t 7.47 000's t 7.35 000's t 6.817 000's t 3.761 000's t 1.316 000's t 1.112 000's t 1.1 000's t 0.559 000's t 0.293 000's t 0.172 000's t 0.079 000's t 0.07 000's t 0.035 000's t 0.03 000's t 0.025 000's t

0.39999 kg/person 0.384684 kg/person 0.379242 kg/person 0.368358 kg/person 0.335536 kg/person 0.334005 kg/person 0.304924 kg/person 0.277544 kg/person 0.26734 kg/person 0.252375 kg/person 0.24081 kg/person 0.238089 kg/person 0.203396 kg/person 0.200505 kg/person 0.196424 kg/person 0.195233 kg/person 0.193703 kg/person 0.192512 kg/person 0.18588 kg/person 0.182989 kg/person 0.178397 kg/person 0.153397 kg/person 0.136901 kg/person 0.13299 kg/person 0.127888 kg/person 0.127038 kg/person 0.124997 kg/person 0.115932 kg/person 0.063961 kg/person 0.02238 kg/person 0.018911 kg/person 0.018707 kg/person 0.009507 kg/person 0.004983 kg/person 0.002925 kg/person 0.001344 0.00119 kg/person 0.000595 kg/person 0.00051 kg/person 0.000425 kg/person

58

Pollution to Water

Particulates

1770 000's t

30.10127 kg/person

Total Nitrogen Ammoniacal Nitrogen orthophosphate Zn Simazine Atrazine Azinphos-methyl Dichlorvos Azinphos-ethyl Fenitrothion Parathion-methyl Malathion Fenthion Trifluralin Cu Drins Cr Ni Lindane Pb Parathion DDT Tributyltin Endosulfan As CHCl3 CH2Cl2 Cd trichloroethene tetrachloroethene CCl4 trichloroethane Hg pentachlorophenol trichlorobenzene Pesticides PCB's hexachlorobenzene Hexachlorobutadien e Triphenyltin

305 000's t 63.5 000's t

5.186943 kg/person 1.079904 kg/person

30.4 000's t 2.1 000's t 1.895 tonnes 1.435 tonnes 0.87 tonnes 0.825 tonnes 0.72 tonnes 0.64 tonnes 0.605 tonnes 0.6 tonnes 0.555 tonnes 0.485 tonnes 0.459 000's t 0.405 tonnes 0.321 000's t 0.3197 000's t 0.3125 tonnes 0.309 000's t 0.17 tonnes 0.16 tonnes 0.155 000's t 0.13 tonnes 0.0855 000's t 0.0544 000's t 0.04915 000's t 0.01905 000's t 0.01495 000's t 0.01355 000's t 0.00875 000's t 0.0087 000's t 0.0033 000's t 0.00299 000's t 0.00145 000's t 0.001356 000's t 0.000741 000's t 0.000135 000's t 0.000125 000's t

0.516994 kg/person 0.035713 kg/person 3.22E-05 kg/person 2.44E-05 kg/person 1.48E-05 kg/person 1.4E-05 kg/person 1.22E-05 kg/person 1.09E-05 kg/person 1.03E-05 kg/person 1.02E-05 kg/person 9.44E-06 kg/person 8.25E-06 kg/person 0.007806 kg/person 6.89E-06 kg/person 0.005459 kg/person 0.005437 kg/person 5.31E-06 kg/person 0.005255 kg/person 2.89E-06 kg/person 2.72E-06 kg/person 0.002636 kg/person 2.21E-06 kg/person 0.001454 kg/person 0.000925 kg/person 0.000836 kg/person 0.000324 kg/person 0.000254 kg/person 0.00023 kg/person 0.000149 kg/person 0.000148 kg/person 5.61E-05 kg/person 5.08E-05 kg/person 2.47E-05 kg/person 2.31E-05 kg/person 1.26E-05 kg/person 2.3E-06 kg/person 2.13E-06 kg/person

0.00008 000's t

1.36E-06 kg/person

175481 000's t 17251 000's t 96000 000's t 7600 000's t 296332 000's t

2.984295 t/person 0.293377 t/person 1.632611 t/person 0.129248 t/person 5.039531 t/person

Mineral Extraction Stone/rock Clays/earth Sand/gravel Others Total

59

Fossil Fuel Extraction Coal Oil Gas Total Fossil

46009 000's toe 109338 000's toe 84886 000's toe 240233 000's toe

Water

Abstracted Supplied

Waste

Arising

423000 000's t

Transport

Freight

2.37E+08 000's t.km

2.17E+13 litres 7.52E+12 litres

60

0.782446 toe/person 1.859442 toe/person 1.443603 toe/person 4.085491 toe/person 417583.4 litre/person 144539.7 litre/person 7.193694 t/person 4140.837 t.km/person

A12

AN OVERVIEW OF THE ENVIRONMENTAL PROFILES DATABASE

All the information collected in the process is entered into an initial database that processes the data to the desired “per tonne” format. Thus BRE retains a record of the raw data and can easily update it with any changes industry partners may provide. It is this processed data, combined or adapted to produce UK average figures for generic building materials and calculated to include upstream impacts that are the subject of the following databases. BRE have created a series of databases to satisfy the varying needs of construction professionals. To assist in the comprehension of these Profiles, characterised data as well as inventory data is available. The method used is the result of work undertaken at BRE for DETR, ‘Eco-points –a consensus for building’. D1-Restricted Access Database: Materials and Components Inventory Data D3-Public Access Database: Materials and Components Inventory Data The data provided in the project is provided as per tonne inventory data for materials and components, for example “manufacture of one tonne of Portland cement”. This data is in the form of individual Profiles, which provide information about the inputs and outputs involved in extracting, processing or making the material. Thus there will also individual Profiles for “one tonne chalk” dealing with extraction of a raw material and then a Profiles for “one tonne lime” which incorporates the chalk Profiles and also covers the processing of this raw material. The Profiles of upstream material inputs must be added together to achieve the full picture. The only difference between D1 and D3 is that D3 data has been released for public access. D2-Restricted Access Database: Materials Characterised and Normalised Data D4-Public Access Database: Materials and Components Characterised and Normalised Data The data in this database is the information in D1, which has been classified into environmental impact categories and the process contribution to each category calculated i.e. characterised and then normalised to give the contribution relative to one UK citizen. The data in the databases D1 and 2 are not available to the public. However, with the permission of the data providers, this data can be transferred into D3 and D4: D5-Public Access Database: Installed Building Elements Inventory Data In this database, the individual materials Profiles in D1 are combined to provide Environmental Profiles for building elements, on a square meter basis, up to the point of installation. Example building elements are: windows; external walls; upper floors. This database will be available for public access. The individual generic data contributions from each component material are hidden within the element. Where materials are used in elements which have not been included in the Environmental Profiles project, then additional per tonne data are sourced from other databases -see Annex 9. D6-Public Access Database: Installed Building Elements Characterised and Normalised Data The Profiles are based on the same information as D5, but the information has been classified into environmental impact categories and the process contribution to each category calculated and then normalised to give the contribution relative to one UK citizen. D7-Public Access Database: 60 year life Building Elements Inventory Data In this database, the individual materials Profiles in D1 are combined to provide Environmental Profiles for building elements, on a square metre basis, for the life of a typical office building of 60 years. It is in this database that the lifetime information about maintenance, replacement and disposal is applied. This database is available for public

61

access. The individual data contributions from each component material are hidden within the element. D8-Public Access Database: 60 year life Building Elements Characterised Data The Profiles are based on the same information as D7, but the information has been classified into environmental impact categories and the process contribution to each category calculated and then normalised to give the contribution relative to one UK citizen.

62

A13 INVENTORY PROFILE FORMAT

APPROVED ENVIRONMENTAL PROFILE Environmental Profile of Inventory Data Manufacture of 1 tonne/1 m3 [product] for: Quality of data Start Date End Date Source of data Geography

e.g. aggregated responses of average data from 5 UK manufacturers e.g. UK

Representativeness

e.g. Current practice in UK

LCA methodology

e.g. BRE

Allocation

e.g.100% to Product

Date of Data entry Boundary

e.g. Extraction of Raw Material and production to Factory gate

Comments

INVENTORY Inputs tonnes

Materials Input

Water from Water Company

m3 m3

Water from Surface Water

m3

Water from Ground Water

m3

Water Use

Energy Use

Primary Energy

MJ

Outputs Product

tonnes

Co-products, by products, other output for recycling/reuse Emissions to Air

tonnes grams

Emissions to Surface Water Water discharged to surface

m3

E.g. suspended solids

mg

Water discharged to sewer

mg

Emissions to landfill Emissions to incinerator

kg kg

Emissions to Sewer Emissions to Land

63

NOTES on Annex 13 'BRE Approved Environmental Profile' for Inventory data. This Profile can be used for D1 and D3, Materials and Components Inventory Data, D5 Installed Element Inventory Data and D7 60 year Element Inventory Data. 1) This title contains a reference to the product as it is officially recognised, including British Standard numbers where appropriate. For elements, this will refer to the major products of which the element is comprised. The title may also contain a reference to a generic product, such as mineral wool, which contains the average available figures from a number of plants making a wide range of mineral wool products. At a later date, such information may be broken down into more specific categories using the density of different products. 2) Quality of data. This is an abbreviated, user friendly format of the requirements proposed by SPOLD, the Society for the Promotion of Life Cycle Development14 . Age, source, geography and the representativeness of the process are shown. For the data collected by BRE through this project, the latter will be “UK average data”, from a varying proportion of UK industry. For elements, this information will be referenced to the major products of which the element is comprised. LCA methodology refers to the assumptions and standard conversion figures adopted by BRE in the BRE Methodology for Environmental Profiles of Construction Materials, Components and Buildings. The “allocation” entry allows transparency by showing the allocation procedures used for different products. 3) Materials input will refer to all products contributing over 2% of the final mass of the product and those which contribute less but which have a significant environmental impact. Packaging materials are listed separately. This Profile includes the environmental data from the key input materials. 5) Energy sources are listed by type and quantity to recognise the resource depletion associated with their use. 6) Outputs refer to the main product and associated by-products, produced as a result of the manufacture of the main product and to which an allocation of the burdens of the process must be made. 5) Electricity and other fuels are listed individually with their energy content in MJ. 7) 'Emissions to air' represents a summary of: emissions arising from the process, from the combustion of fuels in the process and from the combustion of fuels for transport on site and delivery of materials to the site. 8) Emissions to water usually take place over a range of concentrations. These figures represent total mass of emission based on median concentration and total emission to water.

64

A14 CHARACTERISED AND NORMALISED DATAPROFILE FORMAT This format is suitable for Profiles D2, D4, D6, D8.

Approved Environmental Profile Environmental Profile of Characterised and Normalised data for:

1 tonne of product/ 1 square metre of building element installed/ 1 square metre of building element 60 year life

Quality of Data

ISSUES

Start date End date Source of Data Geography Representativeness LCA Methodology Allocation Date of Data Entry Boundaries Comments UNITS

Climate Change Acid Deposition Ozone Depletion Pollution to Air: Human Toxicity Pollution to Air: Low level Ozone Creation Fossil Fuel Depletion and Extraction Pollution to Water: Human Toxicity Pollution to Water: Ecotoxicity Pollution to Water: Eutrophication Minerals Extraction Water Extraction Waste Disposal Transport Pollution & Congestion: Freight

kgCO2 eq. (100yr)) kgSO2 eq kg CFC11 eq kg.tox. kg ethene eq.(POCP) tonnes oil eq. kg.tox. m 3 tox kgPO4 eq tonnes litres tonnes tonne.km ONE UK CITIZEN

ISSUES Climate Change Acid Deposition Ozone Depletion Pollution to Air: Human Toxicity Pollution to Air: Low level Ozone Creation

12270 kgCO2 eq. (100yr)) 58.88 kgSO2 eq 0.29 kg CFC11 eq 90.7 kg.tox. 32.23 kg ethene eq. (POCP) 4.085 tonnes oil eq. 0.02746 kg.tox. 837600 m 3 tox 8.006 kgPO4 eq 5.04 tonnes 417600litres 7.194 tonnes 4140.84 tonne.km

Fossil Fuel Depletion and Extraction Pollution to Water: Human Toxicity Pollution to Water: Ecotoxicity Pollution to Water: Eutrophication Minerals Extraction Water Extraction Waste Disposal Transport Pollution & Congestion: Freight

65

CHARACTERISED DATA

NORMALISED DATA

66