Jesus Hospital Estate Residents’ Association Sustainable living for the JHERA community February 2007
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Contents 02 03 04 05
Section One: Introduction JHERA History Consultation
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Section Two: The Brief
09 10 11 12 19
Section Three: Design Proposals Design statement Location Drawings Artist’s impressions
20 21 22 23
Section Four: Cost and Structure Quantity surveyor’s report Budget breakdown Structural considerations
24 25 26 27 29
Section Five: Environment and Community Promoting green roofs, roof terraces and roof gardens Mayoral support for environmental and community improvements Renewable energy generation and energy efficiency Community projects
Credits Concept and design Theis + Khan Architects 22a Bateman’s Row, London EC2A 3HH
Environmental strategy XC02 1-5 Offord Street, London N1 1DH
Budget Steven Cuddy 1 Cobham Court, Chester Close, London SW1X 7BE
Proposal design Rob Riche www.robertriche.co.uk
Structural and surveyor’s report F J Samuely and Partners Celtic House, 33 St. John’s Mews, London WC1
Project committee Wanda Briggs, Carol Budd (Chair of JHERA), Sarah Kafala Email:
[email protected] Web: www.jhera.com
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Section One: Introduction
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
JHERA The Jesus Hospital Estate in Bethnal Green encompasses 321 houses within the borders of Wellington Row, Durant Street, Columbia Road and Ravenscroft Street. The Jesus Hospital Estate Residents’ Association (JHERA) was formed in 1979 with the objectives: a. To promote the exercise of the tenants’ rights and improve housing conditions and the environment of the Estate b. To encourage community spirit and organise social activities c. To represent the interests of residents in consultation with other bodies. JHERA has now been a working Residents’ Association for nearly thirty years and has held this same constitution ever since its inception. Over the years, various improvements have been made to the properties on an ad-hoc basis; the most important of these was the internal bathroom. This, however, reduced most of the houses from a three bedroom dwelling into a two bedroom one. The turnover of families moving out due to lack of room was beginning to erode the community. In May 2003 an idea originated by local architects Patrick Theis and Soraya Khan was moved forward – to create a sympathetic roof level extension that would enhance the neighbourhood and increase housing density. They volunteered, in discussion with a committee of residents, to draw up a scheme.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Brief history of the area The Jesus Hospital Estate was established as a charity by James Ravenscroft in 1679, the original land being farmland. The first houses were built in 1822 when it was “the desire of the Charity to erect buildings in keeping with a more civilized lifestyle”. These houses were, however, of such poor quality that they had to be torn down and rebuilt in 1862. During the Second World War, many of the houses on the estate were bombed and destroyed. Many were rebuilt but some were simply cleared to make way for open spaces like Ion Square. In the 1960s the area was considered by London Borough of Tower Hamlets for clearance and demolition but a spirited defence from the Charity and local residents prevented this from happening. Again, in 1971, an application was made by the GLC for a Compulsory Purchase Order which would designate five areas of the Estate as clearance areas resulting in the demolition of 190 houses. After a lengthy public enquiry held at Bethnal Green Town Hall in October 1972, the only area finally designated for clearance was the area now know as Jesus Green. After nearly 300 years, the Charity offered the freehold of each property to those existing tenants who could afford it or to some other landlord. The protection of the neighbourhood (as observed in historical references) remains to this day with local residents strongly supporting the residents’ association, JHERA, and actively participating in local issues and events.
Above: Quilter Street in 1900s. Left: Linda Wilkinson’s book on the history of the area.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Consultation In September 2003 a questionnaire, designed simply to assess whether the residents were in favour of pursuing the idea of a roof level extension, was distributed to all 321 houses on the Estate. The results were analysed at the Max Lock Centre, which specializes in community led projects, at Westminster University. The analysis showed that the majority of resident respondents are in support of the roof level extension. The elected committee of JHERA drafted in a sub-committee and this group collated all the information. After a period of reflection and research and bearing in mind the original brief, an environmentally friendly design was then developed. With overwhelming support for the idea, it is the intention to seek the London Borough of Tower Hamlets’ approval for a combined residents planning application. Note: The Max Lock report is available on request from the Chair of JHERA.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
20th December 2006
Section Two: The Brief
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
The Brief The primary aim of creating a roof level extension is to optimise the existing buildings with a uniform, modern, environmentally friendly addition maintaining the uniqueness of the neighbourhood. At the same time this will increase the density of the dwellings to meet with the increased need for housing capacity in the borough, in line with Mayor Ken Livingstone’s statement: “Well designed higher density housing is crucial to my vision for London… both well designed contemporary housing and the Victorian terraces of a typical London street can deliver just as high a density as many tower blocks. These are the places where a mixture of uses - living, working and relaxing generate character and vitality.”
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
The aims of creating a roof level extension are to: • maximise available space to accommodate growing families or to provide the possibility of home working. • increase the stability of the community, which might have a knock-on effect in raising the level of local services eg schools, GP services, etc. • increase housing density • enhance local biodiversity and water conservation • replace original third bedroom lost to indoor bathroom • maintain a family-oriented area by creating family-sized housing and allow for diversity in central London location [non-white households tend to be larger than white households] • maintain a ‘unique’ sense of community spirit and enhance the local ‘rich mix’ • show that change can be good and modern ideas can be applied to historical situations and buildings After careful consideration as to the character of the buildings and after a consultation period, a design was proposed that would enhance the existing buildings as well as offer an opportunity to implement environmental options, often only associated with new builds. It was also felt that since the greatest number of respondents to the questionnaire indicated that it was the sense of neighbourhood that they valued the most, if an element of this could be included, so much the better.
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Jesus Hospital Estate Residents’ Association 3rd Floor extension Proposal document
20th December 2006
Section Three: Design Proposals
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Design statement The proposal is for a lightweight extension at roof level to provide additional accommodation for the existing two storey houses. The extension creates approximately 23m2 or 246ft2 extra floor space. The design and construction of the extension is to follow sustainable principles to create a building with low energy needs and small carbon footprint. The intention is that the external design for the extension is standardised under a design licence to ensure overall uniformity of appearance and the highest quality construction. It is proposed that the shell of the extension is made off site by a specialist company. The walls and roof would be laminated timber panels using renewable resources which are then clad externally with insulation and weather proof coverings. A planted roof is proposed to slow water run off and enhance the biodiversity. Roof mounted solar and photovoltaic panels are incorporated to supplement water heating and electricity. A combination of zinc cladding and double glazed windows is proposed for the walls. This prefabricated unit can then be installed with the minimum of disruption. The extension is set back from the front wall to minimise its visual impact. This creates a new roof terrace behind the existing front parapet wall accessed via double glazed doors. The proposed flat roof keeps the height of the extension as low as possible. The extension is set away from the chimney stacks to avoid the need to alter their height. Taller chimney pots would be fitted to live flues as necessary. Storage would be created below the new gutter against and between the chimney stacks. This storage could accommodate water recycling equipment. Internally there are various alternative arrangements ranging from one single room to a main front room with smaller back room.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Location within London
Site plan Hackney Road
Proposed allotments and Community Recycling in Ion Square gardens Columbia Road
Proposed energy efficient, roof-level extension to all houses incorporating a terrace, green roof, and renewable energy generation
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
Ground floor plan Existing
February 2007
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
First floor plan Existing
First floor plan Proposed
New stair over existing to new roof level
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Roof plan Existing
Second floor plan Proposed option A: Single space with front roof terrace.
New stair over existing to new roof level
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
Second floor plan Proposed option B: Double bedroom with roof terrace at front. Bathroom and services storage at rear.
February 2007
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Section Existing
Section Proposed
Highly insulated green roof with solar and photovoltaic panels
New stair over existing to roof level
Glazed doors to terrace at front
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Front elevation Existing
Front elevation Proposed
Extension set away from existing chimney stacks
Green roof with solar and voltaic panels
Glazed doors to terrace set back behind existing parapet wall
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
Rear elevation Existing
Rear elevation Proposed
February 2007
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
Artist’s impressions Section across typical street
February 2007
Roof extensions set back from front wall to minimize impact on street and create terrace space
Aerial view
Glazed doors to front terrace space
Prefabricated unit ensures high quality construction and minimizes site disruption
Highly insulated green roof with solar and photovoltaic panels
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
20th December 2006
Section Four: Cost and Structure
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Quantity surveyor’s report The total budget estimate for all works associated with the extension for each house is approximately £65,000. Construction would be in three stages: Stage 1 Replacement of existing roof with new floor and adaptation of existing brick outer walls and chimney stacks. Stage 2 Installation of timber wall and roof panels and double glazed windows and doors followed by roof covering and external wall cladding including insulation. Stage 3 Internal fit out and finishes including new stair connection with the existing first floor.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Budget breakdown per house Preparatory works Scaffolding and protection Remove existing butterfly roof retaining ceilings below Raise party walls (1Nr. Per property) Raise rear parapet wall Repoint and repair internal faces of all retained brickwork New structural deck to take prefabricated addition New waterproofing to structural deck and connection to existing hoppers Preliminaries
4,000 1,200 2,500 1,000 1,300 4,000 6,000 2,500
Total
22,500
Prefabricated unit Solid timber building to form single storey addition External walls finished and watertight Glazed sliding screen to front elevation Roof finished with sedum on single ply membrane Craneage and installation
15,000 1,500 4,000 4,000 3,000
Total
27,500
Integration works (minimum requirement) Trim ceiling joists and install new staircase Provide new electrical installation Wall and ceiling finishes Upgrade all internal doors to fire doors Skirtings trims and architraves Decorations Total Basis The above estimate is based on current tender prices. Exclusions No allowance has been made in the costs for VAT or Professional, Legal and Planning fees.
4,000 4,000 3,000 2,500 500 1,000 15,000
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
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Structural Considerations Single storey rooftop extensions are common throughout the London area. An essential component of the financial viability of such proposals is that the existing structure should be capable of accommodating the new loading regime without the need for strengthening of the loadbearing walls or underpinning of the foundations. The major part of the extra loading that is generated by the proposals comes from a combination of a) the prefabricated roof structure itself and b) the additional dead and imposed loading generated by the conversion of the existing ceiling level construction to a useable floor plus the additional imposed loading that this attracts. The remainder of the new loading comes from the extra triangle of brickwork incorporated onto the rear elevation to level this out. Loads from the extra brickwork to the rear can reasonably be ignored, in structural terms, as the maximum load on the rear foundations will be only slightly i.e. less than 10% greater than currently exists. A preliminary assessment of the new loading regime on the party walls indicates that the loading on these walls could increase by up to 35%. However if we assume that a) the walls are of traditional 229 mm (9”) thick solid brick construction with stepped brick footings to give a footing width in the region of 450 mm and b) that the foundations bear on London Clay the resulting bearing stress on the clay is comfortably within its capacity. Exploratory trial pits should be dug in due course at a few locations to confirm, or otherwise, the validity of these assumptions. The capacity of the party walls themselves to carry the new loading is not, subject to checks on their actual thickness and construction, anticipated to be a problem structurally. With a combination of careful attention to the form and weight of the new construction, and sound existing construction, the proposals should be entirely viable in structural terms without the need for remedial strengthening.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
20th December 2006
Section Five: Environment and Community
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
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Living Roofs: promoting green roofs, roof terraces & roof gardens across London The Mayor of London, Ken Livingstone, and his Chief Advisor on Architecture and Urbanism, Richard Rogers, are promoting access to roof space as part of London’s urban renaissance. The GLA Environment Team has been promoting green roofs to enhance London’s biodiversity and improve building performance. Policies within the London Plan also promote Living Roofs. “Well cared for, attractive and lively external ‘private’ spaces add to the beauty of the street and the sense of community and local civic pride in an area, promoting social cohesion through visual contact and communication. Many of London’s typical urban neighbourhoods – including Georgian and Victorian terraced housing – have the potential for roof gardens and terraces that would make them more attractive to a wider range of potential residents.” “Living Roofs – green roofs, roof terraces and roof gardens – can deliver benefits throughout the city for individuals and for society as a whole, enhancing biodiversity, reducing flood risk (by absorbing heavy rainfall), providing insulation and improving the appearance of our cityscape.” “Cities are places of change; we cannot and should not arbitrarily freeze the urban form and layout of the existing city, letting it develop in a piecemeal and dysfunctional manner. Instead, the emphasis should be on planning the city so that it can adapt to provide liveable communities for all its citizens, while placing an appropriate value on preserving local character and heritage in all its forms.” From 'Green light to clean power' the Mayor of London's Energy Strategy ‘proposal 15’: “The Mayor requires planning applications referable to him to incorporate passive solar design, natural ventilation, borehole cooling and vegetation on buildings where feasible. Boroughs should expect the same.”
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Mayoral support for environmental & community improvements The following text is an extract from the recently published Sustainable Design and Construction: The London Plan Supplementary Planning Guidance in May 2006: “...2.1.3 Buildings Essential Standard Existing building reused where practicable, where the density of development and residential amenity are optimised and where the building conforms to or has the potential to meet the standards for energy, materials, biodiversity and water conservation set out in this SPG...” “...2.3.2 Mayor’s Preferred Standard Existing roof space reused where practicable to create new outdoor spaces and enhance biodiversity alongside the integration of renewable energy...” “...These standards are based on the principle of: Maximising the re-use of existing buildings...” “...Guidance on how this principle can be addressed Maximising the re-use of existing buildings - existing buildings can be refurbished or extended without the need for substantial use of new materials from primary resources. This can provide viable futures for listed buildings yet meet new needs…” “...The re-use of existing buildings should, where other policies permit: l Maximise the re-use of the buildings including the basements and roof spaces... l Where other policies allow, consider increasing the floorspace of the existing building through additional floors and/or extensions...”
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
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Renewable energy generation and energy efficiency The addition of a roof level extension for each dwelling provides scope for the introduction of standalone renewable energy generation and increased energy efficiency. Building integrated photovoltaic panels, solar thermal panels, wind turbines or grass roofs could be offered to the individual household as a series of options depending on the roof location and orientation. Each of these options are suitable for integration into a dwellings existing heating or electrical distribution via new hot water cylinders or electrical relays. High levels of insulation should be added to the new roof and walls. As the majority of the dwellings are terrace, the improved roof insulation should go some way to reducing the overall dwelling heat loss. Sustainable sources of insulation could be considered such as recycled newspaper or sheep’s wool. The use of a green roof could improve the level of insulation further, provide retention of rainfall during storms and add some greenery to a dense urban area.
Solar thermal panels Solar thermal panels capture solar radiation and transfer the heat to water, which is then used for space heating or, more commonly, domestic hot water heating. Water is passed through the panels before flowing to a heat exchanger in the hot water cylinder. The cylinder is usually of the twin coil type so that top up heat can be supplied from the existing gas boiler. Around 2m2 of solar collector connected to a twin coil DHW cylinder should provide around 50% of a typical dwelling hot water demand.
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
February 2007
Photovoltaic panels Photovoltaics convert daylight into direct current electricity. In principle they are the ideal source of renewable energy as they harness the most abundant source of energy on the Earth, the sun. PVs are silent in operation, have no moving parts, and have a long life with zero maintenance levels. PV systems can either be connected to the grid or used as stand alone systems, which are more suited to remote locations. Grid connected systems consist of PV arrays connected to the grid through a charge controller and an inverter which converts the direct current into the more useable alternating current. Building Integrated Wind Building integrated wind turbines could be considered and would provide a strong visual eco statement for the project. These are suitable for mounting on the roof or chimney stack of the building. www.windside.com/products.html
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Jesus Hospital Estate Residents’ Association Sustainable living for JHERA community
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Community Projects JHERA residents also wanted to engage with the rest of the local community (largely Bangladeshi) and it was felt that allotments would make the ideal meeting place. There is an already separated piece of land on Ion Square which could easily accommodate 30 - 40 allotments. This piece of land is, at present, totally under-utilised being used mainly by dog owners for toileting their pets. If the land was turned over to vegetable growing, there would be a need for natural compost which could be generated from local kitchen waste through worm and normal composting methods thus further reducing rubbish destined for landfill.* The added bonus is the opportunity for sales of locally produced organic food with no transport costs. We have also been looking at the viability of a wood chip power plant. We would take our lead from the BedZED (Beddington Zero [fossil] Energy Development) ecovillage in Croydon. The wood chips are generated by local government tree pruning and parks waste. Once again, we would be looking at siting this plant in Ion Square. * Similar to scheme in Hackney by East London Community Recycling Partnership