Excavated earth from trenches to be stacked at least one meter away from edges of trench. Ensure that width and depth of trench is only bare minimum required.
Install socketted pipes with sockets against the direction of flow.
Install covers of inspection chambers, valve chambers etc. only after confirming finished ground/floor levels. Ensure correct seating of cover in the frame. Apply automobile grease in the groove of frame. Install covers of sewer lines minimum 50mm above surrounding finished ground levels to prevent surface water entering the chambers.
Branch pipes to inspection chambers to be installed allowing adequate space for benching and channels. Do not install a branch pipe over another.
All loose ends of pipes to be plugged temporarily till completion to avoid entry of debris, plaster etc.
Sizes of manholes / inspection chambers to be determined based on number of branch entries and depth of drains.
Crown of smaller diameter inlet / branches not to be lower than crown of outlet pipe in manholes / inspection chambers.
Inlets / branches to manholes / inspection chambers not to be connected at acute angles to outlet pipe.
Ensure that “head chambers” on main or branch sewers are ventilated if pipe stacks with vent cowls are not discharging to them.
Provide drop connections on branches / inlets which are more than 600 mm above outlet pipe in manholes / inspection chambers.
When lead joints are to be provided to C.I pipework, complete pouring of molten lead immediately after caulking yarn. Do not leave joint with yarn for long periods. Pouring of lead in a joint to be done in a single operation. Lead joint to be finished at 45° to barrel of pipe by caulking lead firmly into the joint and removing excess lead. Use only purpose - made caulking tools for yarn and lead. Do not carry out lead joint at water-logged locations.
When suspending C.I pipes with lead or sealant joints, try to pre - fabricate sections of pipes and fittings as far as possible. Check pre - caulked joints after installation and caulk again if necessary.
Do not use blow lamps, fire wood, solvent cement etc. in un - ventilated and confined rooms. Observe extreme precautions to avoid accidental fires.
When solvent welded joints are to be done on P.V.C pipework, ensure that the jointing surfaces are clean. Use solvent cement in small tins. Do not leave solvent cement open in tins for long durations. Store solvent cement in a cool place, away from direct sunlight.
When seal-ring joints are used on P.V.C or ductile iron pipes, ensure that the rubber ring is correctly seated in the groove of socket. Ensure that a gap of 10mm is provided at the end of spigot to depth of the socket (in case of P.V.C pipes) to allow expansion of pipe.
Install surface - mounted pipes with permanent brackets / supporting system. Do not use temporary supports such as rope, wire etc. Ensure brackets are spaced correctly and maintain clear gap of 25 to 50mm between pipe and finished surface.
Install vertical stacks only after walls are plastered. Horizontal drain pipes in bathrooms, kitchens etc. to be laid only after erection of stacks ( to ensure that the stacks are in plumb).
Ensure that fasteners on brackets for suspended pipes are not drilled into defective concrete structure. If necessary, shift the bracket.
Ensure that drain pipes in sunken slabs are properly supported prior to filling of sunken areas.
Floor drains to be installed correctly (not tilted) to ensure that water seal is retained.
Ensure proper water proofing of openings made for pipes in sunken slabs and other wet areas.
Ensure that traps on sanitary fixtures have adequate water seals as per relevant specifications.
Water seal of floor traps could be evaporated when installed in dry areas or when fixtures are not drained to floor traps for long periods. Prime water seal of traps periodically to prevent foul gases from drains entering the building.
Ensure that water distribution pipework is self - venting and self - draining. Avoid loops, air - pockets etc. in pipework.
Provide only adequate threads on G.I / P.V.C pipes so that not more than one or two threads are visible after jointing is complete. Avoid un-necessary deep threads.
Where pipes are concealed in walls, ensure that the chase is only bare minimum required. Pipes to be as close to the finished surface as possible.
Provide sufficient space between hot and cold water pipes.
Identify finished wall surfaces correctly prior to installing concealed pipework, concealed stop cocks etc, So that C.P. wall flanges of faucets would fix correctly to finished surfaces. Fix temporary threaded pipe pieces at ends of concealed water supply pipes and ensure that they are perpendicular to walls.
Install union joint on water supply pipes after each isolating valve.
Do not disturb or re-locate pipes after completion of hydraulic testing. Cover up concealed pipes / pipes in trenches after testing. Ensure that tests are witnessed and certified by concerned authorities.
Where possible, avoid use of reducing sockets by using reducing elbows / branches etc - to minimize number of fittings and joints on pipe-work.
Avoid chasing - in water supply pipes behind mirrors at vanity basins.
Ensure ends of pipes are cut square and true and remove burrs inside and outside prior to making joints.
While jointing soft copper tubes, re-round the ends using a proprietary tool.
Clean outside of copper tube and inside of copper fitting with fine sand paper or steel wool prior to effecting solder joint. Wipe off any excess flux.
Soldering of joint on copper tube to be completed in single operation, allowing flame to move around the joint continuously. Completed joint to be allowed to cool without disturbance.
Use only brass or stainless steel screws for installation of sanitary fixtures. Use nylon washers while fixing screws to vitreous china appliances.
Use only P.T.F.E tape for jointing C.P fittingss uch as faucets and showers.
Do not use spanners, pliers etc. directly on chromium plated fittings - use temporary protective wrapping.
Do not pull out vertical inlet pipe of bottle traps since this could render the water seal ineffective.
Ensure correct seating of rubber gaskets on W.C pan connectors.
Use correct waste couplings – with or without slot for overflow - for wash basins, based on type of wash basin.
P.V.C pipes should be stacked on level grounds. Alternatively, supports should be provided at base at 1.5M centers. Stack should not be more than seven layers high. If pipes of different sizes are stacked together, the largest diameter should be the lowest. Small pipes may be nested inside larger pipes.
Retain G.I coupling at end of G.I pipe till pipe is to be installed. Clean, inspect and if necessary, re - thread the factory - threaded pipes prior to installation.
Ensure that pipes are straight ( not bent ) prior to installation on vertical stacks and suspended lines.
Do not leave P.V.C pipes exposed to sun and unprotected - before or after installation.
Inspect C.I pipes and fittings for cracks prior to installation. A clear ringing sound should be heard when mildly struck with a light hammer.
Remove factory pasted stickers / paper from vitreous china sanitaryware and inspect for cracks prior to installation.