Draft

1 INTRODUCTION

2 A. Definition The plumbing in a six-door cottage includes the installation of pipes, plumbing fixtures and other apparatus necessary in the design, installation and maintenance of plumbing. There are two pipes known as the water supply and drainage pipes in which supply pipes convey and supply water while drainage pipes carry off the used water. The used water is generally discharged and disposed into a common sewer or other place of disposal in a healthy and sanitary manner.

B. Purpose Basically, plumbing is installed for personal comfort and convenience as well as sanitation and public health measures. It has two main objectives, which are to supply water to different parts of the cottage and to remove and discharge human excrements and other substances out of the cottage. That is possible if there is enough water supply and proper plumbing installation based on the requirements enumerated by the National Plumbing Code.

3 For an effective water supply, there must be sufficient quantity of water to supply the plumbing fixtures and the prevention of backflow of used water into the water supply system. Backflow is the flow of water or other liquid mixture or substances into the distributing pipes of a supply of water from any source, other than its intended source. In other words, backflow brings danger to human health because it may contaminate the water supply. Indeed, it is important to realize the importance of sanitation actions in the form of an efficient and effective water supply and sewage disposal.

C. Principle

Here is a general set of principles which can be used to guide us is found in the Recommended Minimum Requirements for Plumbing developed by the Bureau of Standards, U.S. Department of Commerce. These basic plumbing principles were written to meet the minimum sanitary requirements for all parts of the country, after due consideration of differences in climate, building codes, and methods of sewage disposal: All premises intended for human habitation or occupancy shall be provided with a supply of neither pure and wholesome water, neither connected with unsafe water supplies nor cross-connected through plumbing fixtures to the drainage system. If such premises abut on a street in which there is a public sewer, they shall have a connection, if possible, a separate connection, with the sewer. Buildings in which water closets and other plumbing fixtures exist shall be provided with a supply of water adequate in volume and pressure for flushing purposes by pipes of sufficient size to supply such water without reducing pressure at other fixtures. Plumbing systems shall be maintained in a sanitary condition and will be designed and constructed to guard against fouling and clogging, but with adequate and accessible cleanouts in case, such stoppages should occur. Plumbing fixtures shall be made of smooth, nonabsorbent materials, shall be free from concealed fouling surfaces, and shall be set free of enclosures, with each fixture or combination fixture provided with a separate, accessible, self-scouring, reliable, water-seal trap placed as near the fixture as possible. Drainage system piping shall be so designed and constructed as to be proof for a reasonable life of the building against leakage of water or drain air due to defective materials, imperfect connections, corrosion, settlements or vibration of the ground or building, temperature changes, freezing, or other causes. The plumbing system shall be subject to a water- or air-pressure test and

4 to a final air-pressure test in such a manner as to disclose all leaks and imperfections in the work. House drainage systems shall be so designed that there will be an adequate circulation of air in all pipes and no danger of siphoning, aspiration, or forcing of trap seals under conditions of ordinary use. The soil stack shall extend full size upward through the roof and have a free opening with no danger of clogging from frost or roof water draining into it or of any air from it passing to any window. If water closets or other fixtures exist in buildings where no sewer is within a reasonable distance, suitable provision shall be made for disposing of house sewage by some method of sewage treatment and disposal satisfactory to the health authority having jurisdiction. Where backflow of sewage is possible, provision should be made to prevent its overflow in the building.1

The principle of proper plumbing installation must be achieved safely for the prevention of spread of disease. The horizon of possibility in the spread of disease is so true and of satisfactory public interest that is the reason why the National Plumbing Code is regulated to promulgate municipal ordinances. The health and safety requirements prescribed by the National Plumbing Code has a set of rules of the standards of design, installation and maintenance of various plumbing fixtures and other related installation subject to human health and sanitation.

1. Requirements a.

Drainage system. There are established requirements enumerated below

for an effective drainage system:

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www.icivilengineer.com

5 That all pipe joints must be well fitted and tightly connected with each other to prevent leakage of gas and liquid. The drainage pipe should be graded or inclined properly for a downward gravity flow of water towards the main sewer line or to the septic tank. The drainage pipe should be provided with adequate cleanout accessible for repair in case of stopping. The drainage system must be provided with ventilation pipe that will convey gases to the atmosphere where it can do no harm to human health. That except for water closet, each fixture should be provided with suitable trap that will prevent backflow of gases. The drainage system must be vented to avoid siphonage or backflow to the water seal.2 Plumbing ventilation is one of the most important elements in drainage pipe installation because it is intentionally designed to maintain a balance atmospheric pressure to prevent the existence of trap seal loss, retardation of flow and disintegration of plumbing materials, which may attribute to unpleasing factors that will unsatisfactorily bring harm to us.

b.

Water distribution. For health and safety purposes, it is important to plan

the water distribution so as to attain a satisfactory chemical and bacteriological quality. This can prevent water borne diseases and other cause. The following elaborated below must be known:

The system must be provided adequate supply of water, with adequate pressure up to the extremities of the system. The safety and quality of the water should not be impaired by the defects in the system. It should be provided with sufficient valves and blow offs to allow repair work without undue interruption of service o some areas and to allow the flushing of the system. There should be no unprotected open reservoir or cross connections with inferior water system to enter the distribution system. The water system should be tight against leakage. The main and branches connection should not be submerged in surface water, or

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

6 subjected to any source of contamination. The water system detail design shall afford effective circulation of water with minimum number of dead end mains.3

It is only through planning and knowing the essence of adequate water supply since insufficient supply may cause defects and contamination in the system. It is necessary to be aware of the safety precautions and be protected against leakage, which may lead to bursting of pipe joints to ensure health and sanitation.

2.

Hydraulic principle. In plumbing, pressure plays an important function in the

flow of fluids. It is the force needed for the water to move inside the pipe. It is the only means necessary to overcome friction. There are two forms of pressure namely the static pressure and the normal pressure. Static pressure is the pressure exerted by the water at rest. One example of static pressure is the pressure exerted by the water at the base of a water service pipe when the water is not moving. The water service pipe is the pipe from the water main or other source of water supply to the cottage served. On the other hand, normal pressure refers to the pressure range measured over a period of twenty-four hours. Normal pressure ranges from thirty to forty pound per square inch. Lower than this may result to insufficient flow of water supply especially during simultaneous use of the plumbing fixtures. Whereas, water pressure greater than fifty pound per square inch may cause undesirable pipe hammering or even breaking of pipe joints.

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

7 Pascal’s law states that the pressure on a fluid is equal in directions and in all parts of the container.4

Pascal’s statement can be restated in the formula given below:

P

F A

(1)

Where F= force, N A=area, m2

Meaning to say as pressure is exerted on water inside the pipe, liquid flows of equal part and direction towards to the cottage tank going to the distributing pipes of plumbing fixtures located elsewhere in the cottage. The liquid runs freely or rises to the same level in all parts of the pipe.

The pump is placed underground the cottage. It is connected to the source of water supply, which is also laid underground along the streets where the house sewer pipe is connected.

A pump is designed to pump or raise the water from a lower elevation in the water supply system to a higher elevation going to the roof of the cottage of which tank is located. The input power (Pinput) of the pump is electrical energy and its output power (Poutput) is the flow energy. The equation given below is the

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Gillesania, Diego T. Fluid Mechanics and Hydraulics. GPP Gillesania Printing Press, Philippines, 2003

8

energy equations with pump where



is the summation of kinetic and

potential energies:5

  HA  HL   1

Where

å

= 1

v12 P 1 + + Z1 at 2g 

å

= 2

v22 P 2 + + Z2 at 2g 

(2)

2

lower elevation higher elevation

Equation 2 would then become the mathematical expression of Bernoulli’s theorem in which its principles are applicable to the solution of problems in the flow of fluids:

v12 P 1 v22 P 2 + + Z1 + HA= + + Z2 2g  2g 

Where

å

= 1

v12 P 1 + + Z1 at 2g 

å

= 2

v22 P 2 + + Z2 2g 

(3)

lower elevation

at higher elevation

HA= pump HL= head loss due to friction

5

Gillesania, Diego T. Fluid Mechanics and Hydraulics. GPP Gillesania Printing Press, Philippines, 2003

9 The equation 3 means that if water is pumped to the tank, the water from the tank is distributed to different fixtures of equal total energy plus the energy lost by friction due to flow between them.

The flow energy of the pump would then become equation 4 where Q is the discharge of water and γ is the specific weight of the unit volume of a fluid flowing.6 Poutput=QγHA (4)

A general expression for the flow of fluids can be expressed as:7

Hf

=

Lv2 d2g

or Q=AC√RS

(5)

In which f= friction factor, depending on character of wall or conduit g= acceleration die to gravity l= length of pipe or conduit d=diameter of the pipe or conduit Hf= loss of head due to friction in conduit C=coefficient R=hydraulic radius of the conduit S=hydraulic gradient or S =

hf l

Elaborated below are certain factors included in the flow of fluids through pipes:

6 7

Gillesania, Diego T. Fluid Mechanics and Hydraulics. GPP Gillesania Printing Press, Philippines, 2003 Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960

10 Head loss due to friction hf, in a length of l of the conduit. The magnitude of hf is expressed in terms of the height of a column of the fluid flowing in the conduit. The rate of flow Q that is, the quantity of fluid passing a cross section of a conduit in a unit of time. The velocity of flow V, that is the distance of the fluid particle travels in a unit of time in that cross section where Q is measured. The inside diameter of the conduit d, for circular pipes or its hydraulic radius R for shapes other that circular. The roughness of the conduit wall expressed in various terms such as C, f, n and k and determined empirically for particular fluids and conditions of flow. The density of the fluid, µ and the viscosity of the fluid, ρ.8 Given below is the Hazen and Williams’s formula or the flow of water in pipes under pressure:9 V=Cr 0.63 S 0.540.001-0.04 (6) Where c= a coefficient depending on the roughness of the pipe r= hydraulic radius of the pipe, ft=d/4 S=hydraulic gradient=hf/l d=diameter of pipe, ft V=velocity, fps The values of c are given in table 1.

Table1: Values of coefficients10 Kind of pipe Formula Cast iron, 20 yrs old, V=Cr 0.63 S 0.540.001-0.04 tuberculated Cast iron, new tar coated V=Cr 0.63 S 0.540.001-0.04 Cast iron, cement lined, V=Cr 0.63 S 0.540.001-0.04 centrifugal process Cast iron new, bitumastic- V=Cr 0.63 S 0.540.001-0.04 enamel-lined Wrought iron with new V=80.2d0.678 S0.543 coupling Steel, riveted and welded H= KV1.9/d1.1

8 9

Coefficient C= 100 C= 135 C=150 C=155

K=0.38 to 0.48 C= 130 to 110

Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960 Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960

10

Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960

11 Concrete

H= KV2/d1.5

K= 0.33 to 0.465 C= 145 to 115 Babbit, Harold E. Plumbing. McGraw- Hill Book Company, Toronto, 1960

PLUMBING MATERIALS A. Underground Water Supply and Drainage Pipes Explained below are the material used and its selected fittings used in underground and water supply drainage pipes.

1.

Cast iron pipe. Cast iron pipe have been known the most popular and generally

used material in drainage system because of its distinctive property compared to other materials. It is durable and conveniently installed of buildings not more than twenty five storeys high. Cast iron pipe is not advisable to use to buildings of more than twenty-five storeys high because it may result in leaking of pipe joints.

However, cast iron pipe has its limited design. It is affected by corrosion which is caused by the action of certain gases like carbon dioxide, sulfur oxide and methane forming solutions of carbonic and sulfuric acids. These acids are responsible for the rusting of its metallic material cause by the chemical reaction to take place. Cast iron pipe is classified into two types. These are the SV type, which is generally used for building installations and the XV type known as the extra duty pipe used for underground installations. Cast iron pipes vary in different designs and purposes classified as the standard pipe, single hub pipe, double hub pipe and hubless pipe.

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The standard pipe which is used for a well-fitted hub and spigot connections. The single hub pipe which is recommended with the length of the pipe needed is more than 150cm long wherein cutting is not necessary. The double hub pipe which is preferred when a piece of pipe needed is more than 150cm long. When pipe is cut, both ends has hub to serve as joint connector. The hubless pipe which is used in lieu of the single hub to do away with caulking of joints. It is cheaper and easily connected using a neoprene rubber sleeves.11

Refer to the figures shown below fort the four varieties of cast iron pipe:12

Figure 1: Single Hub Pipe

Figure 2: Double Hub Pipe

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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Figure 3: Hubless Pipe

Figure 4: Standard Pipe

14 Each varying pipes and its recommended uses are applicable in determining the type of pipe that is appropriate in a given length of cast iron pipe required to connect the plumbing installation. They serve, as a reference on what type of pipe shall be used.

2.

Fittings.

There are three types of end which are standard to cast iron pipe and fittings. These are known as the bell-and-spigot, flanged and screwed. Bell-and-spigot ends are used principally or underground work and in buildings where there is ample space for the larger dimensions of the fittings and for caulking operations. Flanged ends are used within buildings where space is limited. The pipe sections being held together by bolts, sometimes with gaskets between the flanges and sometimes with watertight machine-faced flanges. Threaded or screwed ends are used in small pipes in general practice, although they are available in pipes up to 8 and 10in. in diameter. Flanged fittings and threaded fittings are more expensive than bell-and-spigot. They require more accurate cutting and fitting and they lack the adaptability of bell-and-spigot pipe to the slight changes in dimension or direction that are sometimes met in installation. When properly fitted however, they are easier to handle and they can be installed more quickly than bell-andspigot ends. The use of any fitting other than standard may be costly and time consuming in design, manufacture and installation. Therefore, the use of nonstandard fittings should be avoided and ingenuity exercised.13

For the bell-and-spigot end fittings, refer to the following figures shown below:14

Figure 5: Sanitary Branch

13 14

Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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A B C D E

2in 10.6 13.1 26.3 20 6

3in 13.1 16.9 31.9 25 10

4in 15 18 35 27.5 11.3

5in 16.3 20 37.5 30 12.5

6in 17.5 21.3 40 32.5 13.8

8in 21.9 25.3 51.3 42.5 16.6

3x2 11.9 16.3 29.4 22.5 10

4x2 12.5 17.5 30 25 11.3

4x3 13.8 18.1 32.5 22.5 11.3

5x2 12.5 18.8 30 25 12.5

5x3 13.8 19.4 32.5 25 12.5

5x4 15 20 35 27.5 12.5

Table 2: Dimensions of Sanitary Branch Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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Figure 6: Long Sweep

Table 3: Dimensions of Long Sweep 2in 3in 4in 5in 6in 8in A 6.9 8.1 8.8 8.8 8.8 10.3 B 26.9 29.4 31.3 32.5 33.8 37.8 C 27.5 30 32.5 33.8 35 41.3 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

Figure 7: Single Y branches

Table 4: Dimensions of Single Y branches 2in 3in 4in 5in 6in A 16.3 20.7 24.4 27.5 30.6 B 26.3 33.1 37.5 41.3 45 C 20 26.3 30 33.8 37.5

8in 38.3 57.5 48.8

3x2 18.9 29.4 25.5

4x2 20.9 30 22.5

4x3 22.7 33.8 26.3

5x2 22.2 30 22.5

5x3 24.1 33.8 26.3

17 D

10

13.8

16.9

20

23.1 29.5 12.5 14.4 14.6 16.3 17.5 0 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

For the flanged end fittings, refer to the following figures shown below:15

Figure 8: Reducing Short Tee Wye

Table 5: Dimensions of Reducing Short Tee Wye (mm) 30x3 50x3 50x3 63x3 63x3 63x5 75x3 75x5 100x3 100x50 2 6 8 2 8 0 8 0 8 A 109 111 123 128 128 138 127 144 145 145 B 69 70 75 81 81 92 83 91 102 102 C 69 67 72 75 75 78 73 81 84 84 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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For the screwed end fittings, refer to the following figures shown below:16

Figure 9: Reducer

Table 6: Dimensions of Reducer 3x2 4x2 4x3 5x2 5x3 5x4 6x2 6x3 6x4 6x4 8x2 A 9.4 10 10 10 10 10 10 10 10 10 11.3 B 11.9 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 12.5 15 C 18.1 18.1 18.4 18.8 19.4 19.9 18.8 19.4 20 20 21.3 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001

B. Water supply within the cottage Elaborated below are the material used and its chosen fittings for water supply pipe within the cottage:

1.

Plastic Pipe. Plastic pipe is a product of innovation, which is recently developed in

the field of plumbing. It has acquired worldwide acceptance after it has proven itself to be superior in water supply and drainage pipes. 16

Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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According to Dick Demske: Many codes have not been updated since the days when plastic was still in the test tube stage, and therefore do not make any mention of the type of plastic piping that are in widespread use today… Building authorities have a reputation for hard headedness and it is not unknown for them to require the tearing down of installation that does not conform to their codes.17

Basically, there are two types of plastic pipes. These are classified as the rigid type and the flexible type. One of the many pipes of rigid pipe which is commonly seen in plumbing installation inside the served cottage is the polyvinyl chloride (PVC).

Enumerated below are advantages of plastic pipes:

Plastic pipe is more resistant to rust and corrosion. Water conveyed by plastic pipe has no pipe tastes. The extreme smooth interior surface prevents the buildup of scale, rust and foreign material that often impedes flow through metallic pipes. There is no turbulence of water and therefore, has a minimum resistance to flow. PVC pipe and fittings weighs about 1/5 of the metal pipe. They are easily and quickly installed through solvent cementing. Plastic pipes are cast in longer length and easy to cut as well as to install. PVC pipe can be connected to existing metal pipe using a threaded adapter. PVC is virtually acid proof to any chemical use in recommended strengths around the home. No special tools are needed for installing PVC except a ruler to measure and a saw to cut.18

Despite the superiority of plastic pipes over others, not all plastic pipes that are being sold and available in the market are appropriate for plumbing installation. Reputable manufacturers honestly said that other plastic pipe ate doubtful for plumbing use since 17 18

Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

20 most of the plastic pipes are produced from synthetic resins, which means that the chemistry of plastic pipe is confusing and that the finished product could appear in great forms, varieties and colors. Furthermore, they must not be exposed at higher temperature because they tend to have low strength, which may result in cracking. Therefore, the customers must be aware of certain extension brought by the plastic pipe.

2.

Fittings. Shown below are selected fittings for water supply within the cottage:19

Figure 10: 90 o Threaded Elbow

Table 7: Dimensions of 90oThreaded Elbow a b A B C D 20 13 30 27 11 14 25 20 35 33 14 17 32 25 45 39 17 22 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001

Figure 11: 90o Threaded Tees

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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Table 8: Dimensions of 90o Threaded Tees a b A B C D 20 13 30 27 11 14 25 20 35 33 14 17 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001

Figure 12: 90o Elbow

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Table 9: Dimensions of 90o Elbow a A B C 20 26.5 27 11 25 32.5 33 14 32 40 39 17 40 49 49 23 50 60.5 59 28 63 75 72 34 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001 C. Trap A trap is scientifically designed for the purpose of prevention of backflow gases coming from the sewage system passing into the outlet of the fixture that may affect human health. A trap must be self-cleansing. It must allow the passage of liquid carrying solids in suspension without maintaining the solid inside the trap and becoming clogged. In other words, it must be provided with an opening between suspensions of the water seal trap in case of clogging of solid substance. Water seal is a column of water that is maintained inside the trap. The requirements of a perfect trap are enumerated below:

23 It must be able to pass used water freely without mechanical aid. It must be able to prevent passage of sewer air either direction whether sewage is flowing or not. It must be self-cleansing. It must have a preferably not less than 2-in deep. It must be strong and proof against leakage from it of gas or liquid. It must have no mechanical or moving parts. It should be provided with a clean out or other means of access to interior in the event of chokage. The cover must be gastight and watertight. It must have no recesses, cavities or pockets that cannot be scoured by the flow of sewage through the trap. It must have no internal projections to catch and hold hair, lint, bits of matches, etc. but must have a smooth inner surface every part of which is automatically scoured by the flow of sewage through the trap. It must have no washers, gaskets or packing on the sewer side of the seal that may decay and cause sewage or sewer air leakage. Where necessary, it must be back-vented. It must not have concealed partitions, tubes or other invisible parts if defects in construction might permit sewer air to enter into the house.20

The National Plumbing Code on traps provides that: “Every trap shall be selfcleansing. Traps for bathtubs, lavatories, sinks and other similar fixtures shall be of either lead, brass, cast iron, galvanized, porcelain or enameled inside or plastic. Each fixture shall b separately trapped by a water sealed trap placed as possible to the fixture except that a set of similar fixture consisting of not more than three wash basins, or a set of three laundry trays or a set of three sinks may connect may connect with a single trap but in no case shall the waste from bathtub or other fixture discharge into a water closet trap. No fixture shall be double trapped.”21

PLUMBING DESIGN A. Design Procedures Enumerated below are the procedures in the design of plumbing work and the preparation of plumbing drawings:

20 21

Babbit, Harold E. Plumbing. McGraw-Hill Book Company, Toronto, 1960 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

24 Count the plumbing fixtures and estimate the following: sizes of house sewers, size of water services, size of gas service and hot water load (Tank size and necessary makeup). Determine if sump pumps or ejector pumps are required. Determine if constant-pressure booster pumps or gravity or pneumatic tanks are required. Note the presence or absence of sufficient slop sinks, fixtures for the handicapped and drinking fountains or water coolers and check any lack with the architect. Notify the electrical project engineer of the electrical requirements of the plumbing work. Check with the HVAC and electrical project engineers regarding space conditions for risers, fire hose cabinets and for required machinery room space. Check the structural drawings for space conditions affecting the plumbing work. Obtain minimum ceiling heights from the architectural drawings or architect and check to see that the plumbing work clears these heights. Note lack of proper pipe stacks and wall thickness for the plumbing work and check this lack with the architect. In general, piping should be run as direct as possible. However except for piping buried underground, all piping should be run parallel to and at right angles to the walls, partitions, etc. and should be neatly grouped in parallel lines. Note piping rising with a storey as “rise”. Note that rising to the storey should be noted as “drop”. Dropping to the storey should be noted as “at ceiling” when exposed and as “in ceiling below” as required. All information received from or given to the architect, owner, local authorities, etc. either in person or in telephone, should be immediately conform to the memorandum wit copies sent t individuals involved. When attending project meetings, detailed notes should be taken at all items of discussion pertaining either the meeting, a memorandum should be written conforming the details discussed to a copy sent to the others present at the meeting. After a project has been scheduled and started, the project engineer should record the memorandum the involved (man days) and any resultant delay in completion, and have this memorandum approved before proceeding with the work involved.22 B. Plumbing Layout Roughing-in refers to actual installation. The roughing-in process in the plumbing pipes proceeds simultaneously with the erection of the structural parts of the cottage. Therefore the walls and floors must be completed first before the installation of pipes. Roughing-in includes the placement of connections of pipes, fittings and fixtures from the connection of the house sewer in the underground at the top of the vent stack

22

Church, James G. Practical Plumbing Design Guide. McGraw-Hill Book Company, New York, 1979

25 extending through the roof and all water lines but not connected to fixtures. Plumbing work that is completely roughed-in is ready for fixtures.

Basically, the first step in plumbing installation is the connection of the house service pipeline with the underground spring water and also of the house sewer line with the public sewer. Water hangers for plumbing stacks are then placed to support the vertical main of a system of soil or waste pipe in the cottage. Soil pipe differs from waste pipe in the way they receive and convey discharges of liquid and solid substances. Soil pipe carries human waste coming from the water closet whereas waste pipe does not receive discharges from water closet but from other fixtures only.

After the installation of supports, water supply and drainage are then placed simultaneously followed by the branching pipe following closely on the erection of riser pipes and stacks. Branching pipes are horizontal pipes that serve the fixtures while riser pipes are the vertical supply pipes, which extend upward from the floor to the next. Lastly, plumbing fixtures are installed after flooring and plastering is completed.

The plumbing plan for the six-door cottage is shown below with its corresponding plumping specifications, symbols and schematic diagram.

26 Figure 13: Perspective of the Six-Door Cottage.

27 Figure 14: Plumbing Plan PLUMBING FIXTURES

28

Plumbing fixtures are installed receptacles, which are supplied with sufficient water and receive all discharges water or wastewater into the drainage system. It comes in varieties of style. It must be selected with dependable quality since they take a lot of abuse, yet expected to remain adequate and sufficient for years.

A. Lavatory A lavatory is a hollow vessel with running water, which is primarily used in washing our faces and hands. It is connected with a waste pipe for draining the wastewater inside the lavatory. The elevation sides are nearly sloping side for easy escape of water in the drainage pipe. It is available in a variety of forms. It comes as rounded, square, oval, rectangular, trapezoidal and triangular shapes. Shown below is a rectangular lavatory installed inside the cottage.

29 Figure 15: Rectangular Lavatory23

The discharge pattern of a lavatory is dependent on the length, diameter and slope of the fixture drain, on the type of stack fitting used, on the type and diameter of the trap, on the side and shape of the lavatory and on the volume of water in the lavatory.24

Wyly and Hints from the tests at the National Bureau of Standards found that the average rate of flow from lavatories and bathtubs could express fairly well by this formula:25

q= 4.33A√h 23

www.icivilengineer.com Manas, Vincent T. National Plumbing Code Hamdbook. McGraw-Hill Book Company, 1st Edition, Toronto,1957 25 Manas, Vincent T. National Plumbing Code Hamdbook. McGraw-Hill Book Company, 1st Edition, Toronto,1957 24

(7)

30

Where q= rate of discharge, gpm A= effective area of the outlet orifice, in2 h= vertical distance from water surface to level of overflow connection, in. B. Water Closet Water closet is a plumbing fixture, which is used to carry human excrements to the drainage system. Water closets are known with different names according to its design, quality, shape and color. With respect to its quality, it must flush down organic wastes quietly and completely. It must function effectively and efficiently and must maintain large amount of standing water inside the bowl to avoid fouling odors and contamination. The figure as shown below is known as the Siphon Vortex water closet installed inside the cottage.

Figure 16: Siphon Vortex Water Closet26

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The Siphon Vortex water closet has the following characteristics:

Although it is acceptably expensive type of water closet bowl, yet, proven to be less noisy and very efficient in its performance. The flushing action of the siphon vortex water closet is through a whirlpool motion of water inside the bowl, followed by a flush down of the liquid and waste completely. Siphon vortex retains a large amount of standing water covering almost the entire interior surface of the bowl. Considering the large amount of standing water retained inside the bowl, it is very sanitary and easy to clean.27 C. Shower A shower is another plumbing fixture installed inside the cottage. It is named as shower because it has an overhead nozzle that sprays water down on our bodies. It is where customers bath themselves with sufficient supply of water.

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

32 Figure 17: Shower28

PLUMBING SYSTEMS

The plumbing system generally includes the water supply and drainage system. It further explains the function of water supply distributing pipes, soil pipe, house drain and house sewer.

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A. Water Supply System The water supply consists of the water service pipe, water-distributing pipes, and other necessary connection pipes and fittings to the cottage being served. Water service pipe is connected underground to the spring water.

Water is the heart in plumbing because without its existence, there will be no plumbing installation at all.

The water conveyed must be exercised with extreme

precautions of organic matter, which includes the animal and human wastes since the source of water supply in the cottage is from underground spring water.

Spring water, is nothing more than a very shallow well with water, taken from a water stratum composed of cervical limestone, sand or gravel, lying a few meters below the earth. Contrary to common belief, spring water is not always free from contamination. Indeed, it is uncertain to conclude that spring water is protected from surface water contamination by impervious formation of the soil. Therefore extreme precautions should be exercised in developing water intended for drinking and household use.29 The fissure wherein the spring water will flow should be enclosed completely with a reservoir of concrete, tile, steel or other impervious materials under the following considerations: The depth of the reservoir walls shall penetrate downward the impervious formations beneath the water producing stratum. The reservoir cover shall be insect proof, free from dust and rainwater. A manhole of the raised curving type, with overlapping cover on its edges terminating in a downward direction, shall be provided with facilities for locking. The reservoir should be disinfected with a chlorine solution, and then flushed thoroughly prior to the submitting of samples for laboratory test. Water from the spring reservoir, shall be declared safe only after the result of bacteriological test. 30

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

34 Shown below is a summarized presentation in the flow of water from the underground spring water to the water supply distribution.

Figure 18: Flow of Water

In water supply distribution, friction is defined as the resistance between the molecules of water. It can be minimized under the following conditions: All the water pipes should be installed straight and direct as possible. The use of turns, offsets and traps should be minimized. Pipes with plain and smooth surface should be used. The use of fittings, stops and other devices connected to the distribution lines should be minimized. All fittings and joints must be connected properly.31

B. Water Drainage System 31

Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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The drainage system includes all piping that conveys wastewater to the established point of disposal. The principal of design of drainage pipes is not similar from the principle of water supply pipes that functions under pressure greater than atmospheric and that may freely flow from a lower to a higher elevation.

The materials for drainage system must be chosen rightfully with respect with the strength, durability and the capacity to resist the corrosive circumstances of wastes discharged into them. Since cast iron pipe is the selected material in the underground water drainage system, it should not be exposed to acid wastes and hot water. The presence of heat is eligible enough to increase the rapidity of the evaporation of water from traps which may caused the undesirable odors to take place and the alternate contraction and expansion of pipes which may loosen joints that has been sealed water tight and air tight.

The requirements for a drainage system can be summarized as follows: It must carry the wastewater rapidly away from the fixtures. The passage of air, odors or vermin from the sewer into the building must be prevented. The drainage pipes must be gastight, airtight and watertight. The pipes must be durable and well installed that slight movements of the building or of the pipe will not cause leakage.32 1.

Soil Pipe. A soil pipe is a drainage pipe that receives and conveys human wastes

coming from the water closet. The National Plumbing Code on soil pipe provides: That, at least one of the vertical stacks in the plumbing system must extend full size through the roof for the following purposes: To ventilate and dispose the sewer gas above the roof, to 32

Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

36 prevent siphoning of the water trap seal by force of suction and to prevent the possibility of back pressure which may force the water seal off the fixture trap. Any structure with a house drain installed must have at least one soil; stack or stack vent, extended full size above the roof not less than 75mm diameter or the size of the drain whichever is smaller. As a greater rule, vent stack must be extended and terminate through the roof of the building. When the roof is to be used other than protection from the elements of weather, the vent stack should b extended no less than 2m above the roof.33

The Plumbing code on soil pipe installation provides that: the soil pipe shall be properly concealed or embedded in columns, walls or partitions and installed prior to the construction of plumbing. The entire installations in building such as the location of fixtures, thickness of the partitions, location of doors and windows, drop ceiling, electrical layout and outlets and their relations with each other shall be considered in the pre planning stages prior to the rough-in work. The soil branch that will directly receive waste from water closet shall b short and direct as practicable. Soil pipe joints shall be tight and free from liquid or gas leak. Installation workmanship shall be strictly in accordance with the standard practice o the trade involved. Soil pipes not embedded in concrete wall, columns or partitions shall be anchored rigidly by means of metal hangers. The changes from vertical to horizontal directions shall be done by using: ¼ bend, long sweep ¼ bend, two ⅛ bend and combination of Y and ⅛ bend.34 2.

House drain. House drain is that portion of the horizontal piping of the drainage

system of a cottage into which all the soil and waste pipes whether vertical or horizontal is ultimately discharged. This house drain is laid outside the cottage foundation wall where it connects the house sewer.

On house drain, the plumbing code provides that: No water closet shall discharge into a drain less than 75mm or 3in. pipe diameter. No more than two water closets shall discharge into any 75mm horizontal soil branch, house drain or house sewer.35 33 34

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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On house drain cleanout, the National Plumbing Code provides that: The house drain shall be provided with adequate number of cleanouts to prevent breaking of the floor, in case of drain stoppage. The location of the cleanout depends upon the good judgment of the plumber where it is accessible in case of line trouble. Any branch of the house drain terminating at a floor drain or fixture shall e provided with 100mm diameter pipe extended at least 2in. above the floor inserted in a 45◦ Y branch in the direction of the drain flow. The cleanout shall be equipped with threaded screw cover provided with a raised head that could be removed easily with a wrench. A cleanout extended above the floor shall not be utilized as a floor drain. The trap of a floor drain shall be placed not more than 50cm below the finished floor line to facilitate cleaning in case of line trouble. A cleanout shall be installed at every 20m-interval distance and also at the base of all soil and waste stack.36 3.

House Sewer. House sewer is that portion of horizontal piping of the drainage

system of a cottage, which connects the house drain and public sewer. The house sewer serves as a continuation of the main drain to the point where the house drain piping ends to its connection into the sewer. This is connected with the main water by a small hole using any form of boring instrument.

General conditions in installing sewer pipes: Secure permits from the sewerage authority. Verify the depth of the house drain outlet. Determine the depth of the connection with the main sewer in the street and the grade of the house sewer. The depth is found by measuring the length of the longest branch of the house drain multiplied by the pre-planned pitch per meter. Add the required 30cm ground covering from the top of concrete floor or 40cm of ground covering without concrete floor. Verify the depth of the connection to be made with main sewer. Remove the manhole cover on both ends. Measure the depth using a meter tape or stick. The grade of the house sewer could be found through the difference between the house sewer and the depth of the main sewer. Additional grade can

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

38 be made with the use of ⅛ bend considered as the most practical method of establishing grade. 37

PROCESS OF INSTALLING A. Cast iron pipe 1.

Measuring length.

In measuring length of cast iron pipe, the end portion that will enter into the hub is added to the face length of the effective distance.38

Figure 19: Face-to-Face Length

See Table 10 for the additional length in cutting cast iron pipe.

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

39 Table 10: Additional length in cutting cast iron pipe Pipe Diameter Engagement Length mm in mm in 50 2 62 6.2 75 3 68 6.8 100 4 75 7.5 125 5 75 7.5 150 6 75 7.5 nd Fajardo, Max B. Jr. Plumbing Design and Estimate. 2 edition, 5138 Merchandising, Philippines, 2001

The additional length is necessary in connecting cast iron pipe into the hub. It is used for one end connection only, but if both ends are inserted into the hub, the length should be doubled.39

2.

Cutting cast iron pipe.

The procedures in cutting cast iron pipes are as follows: The chalk mark is drawn around the pipe. The pipe is laid on sand. With the use of hammer and cold chisel, the scored lines around the pipe is struck gently at first round then continue striking harder all around until the pipe is cut or part off.40

Figure 20: Cutting Cast Iron Pipe

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001 Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

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3.

Caulking joints.

Caulking joints of cast iron pip is done through the following steps: Make sure that the pipes to be joined are perfectly aligned with the spigot centered inside the bell. Wrap the oakum around the spigot neck filling the space around the inner hub. With the use of yarning iron, drive the oakum into the bottom of the hub then, compress firmly to make a solid bed providing 20 to 25mm clearance from the top of the bell. After packing, the joint is sealed with lead monolithically poured around the inner hub at about 3mm above the bell then packed against the hub by the caulking iron tamping it firmly to make a watertight seal.41

Figure 21: Caulking Cast Iron Pipe Joints

B. Plastic pipe Elaborated below are ways in working with plastic pipes:

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Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

41 Measure the face-to-face distance of the fittings to be connected. Add the engagement length before cutting the pipe. Some plastic pipes can be cut with a sharp knife, but all can be cut with hacksaw or handsaw. A rotary pipe cutter should not in any manner be used in cutting plastic pipes. Be sure to cut pipe ends square or at right angle with the axis of the pipe. Work on one joint at a time. Solvent is very quick setting and unforgiving of mistakes. Once an error is committed, the only remedy is to cut the pipe and have it replaced. After cutting, remove the burrs inside the pipe, ream and clean the end portion of the pipe until smooth to allow full contact with methyl ethyl keton (MEK) or simply acetone. However, depending upon the type of plastic being used, there is solvent that needs no cleaning of the pipe before its application. Apply solvent cement liberally using non-synthetic brush to the shoulder fitting and butt end of the pipe. Insert the pipe into the fitting and give it a quarter turn or ¼ turn. The span of time from the cement application to the quarter turning should not be more than 30 seconds. Do not disturb the pipe for several minutes after the quarter turn. Wait for about 24 hours before testing the line under pressure. Drying of the cement must be far enough advances from about 15-20 hours to permit use of the line. In the process of bending, plastic pipe is packed with sand then heated using a flame torch or hot water. Apply pressure gently and gradually when the pipe is soft and ready for bending. Continue bending until the desired curvature of the pipe is arrived at. A metal spring for bending copper tube may be used to prevent flattering of the pipe. Correction or repair of the lines may be done by cutting the pipes at a reasonable distance from the side of the fitting then connect with coupling or socket.42

Figure 22: Repairing Damaged Plastic Pipe

CONCLUSION It is important to know the proper installation and follow the design procedures in plumbing in accordance of the requirements of the National Plumbing Code of the Philippines since improper plumbing is vulnerable to human health and sanitation. 42

Fajardo, Max B. Jr. Plumbing Design and Estimate. 2nd edition, 5138 Merchandising, Philippines, 2001

42 Improper design, installation and maintenance make possible infestations by rats, cockroaches, mosquitoes and other pests. However, their presence can be prevented by proper precautions. Precautions to be taken may include the making of tight joints in drainage pipes, the use of adequate seal in traps, the avoidance of standing water in the presence of light to discourage egg-laying and the use of toxic substances in pastes and glues on pipe coverings to kill wingless insects.