building notes of ch-9 of pokhara university.pptx

building notes of ch-9 of pokhara university.pptx

1. Chapter 9 WATER SUPPLY AND DRAINAGE

2. Contents: Mains of water supply: storage and distribution system: Hot water supply. Drainage of sewage and waste. Rainwater pipes and gutters. Septic tanks. Rainwater harvesting.

3. General principles: Provide adequate quantity of water-supply in the building. Provide sanitary fittings. Provide adequate and effective drainage to building. All water closets, bathrooms, kitchen etc should be grouped on one side of building. All water closets, bathrooms, kitchen etc should be located on at least to one external wall. General slope of floor, terrace should be towards the wall on which drainage pipes are laid.

4. 9.1 Mains of water supply: storage and distribution system: Storage system: Water supply in buildings may be continuous or intermittent. Even in continuous supply, in mains pressure of water may not be sufficient to rise to all floors of building If supply has less pressure, water is first stored at ground tank & pumped. Two types of storage system: Underground storage: At least 3 days water storage Division of 3000 ltr (i.e. 3000, 6000, 9000... Itrs) Made of RCC Accessible by tanker Overhead storage One day water requirement (Capacity not less than 1000 ltr)

5. Overhead tanks: Mild steel pressed plates Reinforced Concrete Stone or Brick Masonry PVC Water distribution system Direct System The supply of water is given to various floors in building directly from the mains. These mains have sufficient pressure to feed the entire floor and water fittings at the highest part of the building. Indirect System The supply of water is given to various floors in building directly from the mains may be done by either by. Feeding water directly into the overhead storage tank provided at roof of the building from where water is supplied to different floors by gravity. Feeding the water into a underground water storage tank then pumping to overhead storage tank from where the water is supplied by gravity.

6. Water distribution methods Gravity distribution. Direct pumping without storage. Distribution by pumps and elevated storage tanks (combined system). Design of distribution system Size of distribution pipes (pressure, velocity etc.) System of layout of pipes (depends upon topography, location and water sources-elevation) Dead-end/free-end/tree system Grid-iron system Circular or ring system Radial system

7. Supply Mains Water-supply pipes are categorized according to the function of the pipes: Trunk or primary pipelines: Municipal large sized pipe laid along the road This should have adequate size to give required rate of flow of water. It can be divided into different sections but has no dead ends. 2. Communication pipes or secondary pipeline: It is pipeline from main to house. This line is also under the control of municipal authority. It has separate stopcock in the place of connection with mains . 3) Service mains or consumer pipeline They are the internal pipes inside the house This is connected to the communication pipes with stopcock. ( A stopcock looks like a tap, but without an outlet spout. It will be between two lengths of pipe, acting as a connector )

8. Hot water supply The supply of hot water to domestic sanitary fittings is usually taken in the form of: gas fired oil fired or solid fired fuel boiler electric immersion heater solar For hot water system, the pipe lines are covered with glass wool or any thermal insulating material to reduce heat loss.

9. Types of hot water system i Direct hot water system. ii. Indirect hot water system. i Direct hot water system . .

10. ii. Indirect hot water system.

11. 9.3 Drainage of sewage and waste The water used in various areas of a building like kitchen, bath, WC etc. should be properly collected and disposed without any risk to the health of occupants. Similarly, rain or storm water from roof and paved areas of building and ground surface should be collected and discharged without flooding the area. Method of carrying refuse Conservancy system Water carriage system Separate (for sewer and storm) Combined Partially combined

12. Principle of house drainage Provide by the side of the building. Provide adequate size. Insure appropriate level to drain-out from lowest level. Provide proper gradient for self-cleaning velocity. Provide non-absorbent type foundation. 9.4 Rain water pipes and gutters Drainage of rain water from roof and premises(home). Water drain from the roof through pipes and gutters. Water drain from the ground to the sewer line by the road-sides. Pipe and gutter size depends upon the roof area and the intensity of rain.

13. Gutter: A narrow trough or duct which collects rainwater from the roof of a building and diverts it away from the structure, typically into a drain. Trap: Trap is a fitting provided in a drainage system to prevent entry of foul air or gases from the sewer or drain into the building.

14. 9.5 Septic tanks Septic tank is a masonry tank in rectangular shape having two compartments with bed slope and RCC cover. The functions of septic tank are: To hold incoming night soil within a detention period of one day. Night soil is liquid waste product collected from pan, urinal, commode, bidet etc. To digest anaerobically, the precipitated solid within the detention period. To store the digested sludge till its removal.

15. Design of septic tank The size of the tank is depends on; the number of users. the amount of dilution water in the sewage. The minimum liquid capacity shall be one cubic meter. The length of the tank should be 2 to 4 times the width. Septic Tank capacity V = V1+V2+V3 V1= Space required for settling of incoming sewage. =Quantity of sewage (Q) x Detention time (T) V2= Space required for digestion of sludge=0.0425m3 V3= Space required for storage of digested sludge until disposed (depends upon cleaning period of tank) Depth: (1-3)m and free board: 0.3-0.5m L/B: 2 to 4. ( Detention time: it is the time between entry of water into settling basin and flows out from the outlet to soak pit )

16. Soak pit It is a simple pit dug in the ground for disposal of effluent from a septic tank. The pit is generally circular in shape. It can function effectively where the soil is porous and water table is low. Pit is generally filled with rubble or brick bats. Design of soak pit is based on the ability of soil, found at a depth between one and three meters, to absorb water. Soak pit can act effectively when water table is sufficiently below ground level and soil is of porous type.

17. 9.6 Rain water harvesting Rainwater harvesting is collecting the run-off from a structure or other impervious surface in order to store it for later use. Uses of rainwater: Connect rainwater collection system to irrigation/sprinkler system. Wash your vehicles. Wash your pets. Refill your swimming pool. Rainwater can be harvested in a variety of ways: Directly from roof tops and stored in tanks. Monsoon run off and water in swollen streams during the monsoon are stored in underground tanks. Water from flooded rivers can be stored in small ponds.

18. Expected Benefits : Prevents water wastage by arresting run off. Prevents soil erosion and reduce flood. Increases water availability and improves water quality. You have total control over your water supply (ideal for cities with water restrictions). It can provide an excellent back-up source of water for emergencies. It uses simple technologies that are inexpensive and easy to maintain.

19. Tutorial Explain about direct and indirect method of heating

20. Chapter-10 Electrical services

21. 10.1 Residential and Commercial requirements Residential requirements Usually lighting is desired after the sunset or in the dark interiors where sun does not reach properly. In a residence it is also present in the form of garden lights and other interior and exterior lighting. Heating is in the form of stoves and heating system including A/C . Power is necessary to run water pumps, computers, T.V. and other appliances and gadgets. Commercial requirements The fundamental objective of commercial building design is to provide a safe, comfortable and attractive environment for living, working, and enjoyment. Following are the commercial requirements of electrical services Lighting interior and exterior, both decorative task and general lighting . Fire alarm systems fire pumps and sprinklers.  Communication telephone, telegraph, satellite link, building to building communications (computer link, close circuit television, code call, doctors and nurses call) and variety of other signal systems . Transportation : elevators, moving stairways . Space conditioning: Heating, cooling.  Plumbing; Hot and cold water systems and water treatment facilities . Refrigeration use for food handling .

22. 10.2 General Principles of internal wiring A switch board is to be installed 1.25 meters above the floor. All plugs and socket-outlets are to be 3-pin type . Adequate number of socket-outlets in room to avoid flexible chords. Unless otherwise specified, all ceiling fans are to be hung 2.27 meter above the floor. .The load on each power sub-circuit is to be normally restricted to 3000 watts. No switch and fuse to be provided in earthen conductor . F or estimation of internal wiring it is necessary on the part of estimator that he/she should be fully knowledge with the general rules followed for internal wiring. Every installation is to be properly protected near the point of entry cables. The conductors used are to be of such a size that may carry load current safely.

23. 10.3 Wiring systems Wiring is done for light, fan, heater, heater-cooler, air-conditioner and obtaining electrical supply of domestic appliances . Points to note for wiring: Use of best material Careful wiring Minimum numbers of points in a room Minimum numbers of appliances to be used at a time from one plug point . Wiring material Main switch , PVC wires , Earthing wire , Switch boards (PVC, wooden) ,Plugs ,Wooden casting , Conduit pipes, elbow, sockets etc. Screws ,Bracket, j unction box , Fuse kits , Bulb

24. Factor affecting the choice of wiring Durability – Type of wiring selected should confirm to standard specifications, so that it is durable i.e. without being affected by the weather conditions. Safety – The wiring must provide safety against leakage, shock and fire hazard for operating personnel. Appearance – Electrical wiring should give an aesthetic appeal to interiors . Accessibility – The switches and plug points provided should be easily accessible. There must be provision for further extension of the wiring system, if necessary . Maintenance cost – The maintenance cost should be minimum. Mechanical safety – The wiring must be protected against any mechanical damage.

25. 10.4 System of house wiring a ) Cleat wiring b ) Batten wiring c ) Conduit wiring a. Cleat wiring – This system of wiring consists of wiring on walls or ceilings by means of porcelain cleats, plastic or wood. Cleat wiring system is a temporary wiring system therefore it is not suitable for domestic premises . The use of cleat wiring system is over nowadays . Advantages It is simple and cheap wiring system. Most suitable for temporary use. Fault can be seen and repair easily . Disadvantages Appearance is not so good . There is always risk of fire and electric shock. It can’t be used in important and sensitive location and places. It is not lasting, reliable (trustworthy) and sustainable wiring system.

26. b) Batten wiring Single core or double core or three core cables with a circular shape cables are used in this kind of wiring. Mostly , single core cables are preferred . Advantages Wiring installation is simple and easy Cheap as compared to other electrical wiring systems Good appearance  Repairing is easy . Disadvantages Can’t be installed in the humidity, chemical effects, open and outdoor areas. High risk of fire. Not safe from external wear and tear and weather effects(because, the wires are openly visible to heat, dust, steam and smoke) Heavy wires can’t be used in batten wiring system

27. c) Conduit wiring There are two additional types of conduit wiring according to pipe installation, they are: i . Surface conduit wiring ii. Concealed conduit wiring i . surface conduit wiring If conduits installed on roof or wall, it is known as surface conduit wiring. In this wiring method, surface wiring run over walls or under ceilings. PVC channels are used to cover the wires completely . ii. Concealed conduit wiring If the conduits are hidden inside the wall slots with the help of plastering, it is called concealed conduit wiring. It is most popular, beautiful, stronger and common electrical wiring system nowadays.

28. Advantage of conduit wiring system There is no risk of damage the cables installation. It is safe from corrosion and risk of fire. It is reliable and popular wiring system. long- lasting wiring system . Disadvantages of conduit wiring system It is expensive wiring system. Very hard to find the defects in the wiring. Installation is not easy and not simple.

29. Type’s of conduit Following conduits are used in the conduit wiring system in both concealed and surface conduit wiring Metallic conduit Non- metallic conduit 1. Metallic conduit- Metallic conduits are made of steel which are very strong but costly as well. 2. Non- metallic conduit- A solid PVC conduit is used as non-metallic conduit nowadays. This is flexible and easy to bend. Size of conduit The common conduit pipes are available in different sizes generally 13, 16.2, 18.75, 20, 25, 37, 50, 53 mm diameter or 1/2, 5/8, 3/4, 1, 1.25, 1.5, and 2 inch in diameter.

30. 10.4 Trunking , busbars and duct for electrical distribution Trunking – Trunking is the term employed to an elaborate installations consisting of heavy cables in the form of metal or plastic member which accommodate such cable. It is fixed horizontally or vertically to wall, floor and ceiling of the building. Busbars A bus bar is a round or rectangular copper or aluminum bar conductor of standard length. It is supported at intervals by insulated carriers; they run inside solid enclosures of galvanized steel trunking with insulating supports. They can also carry more current than cables with the same cross-sectional area . Ducts Ducts are created in the building which accommodate the electrical, sanitary and plumbing systems. Horizontally, they are taking inside the false ceiling.

31. Tutorial Advantage and Disadvantage of Trunking , busbars and duct for electrical distribution , Metallic conduit,Non - metallic conduit Safety precaution