Putting in drain pipes, do this first
Putting in drain pipes, do this first
The first thing that you will need to think about when undertaking any DIY plumbing and sewage are the rules issued by your Local Authority.
The local authority will definitely require you to submit complete drawings of the proposed changes or replacement of your existing drain and sewage system to ensure that your work is in conformity with local rules. However, you will probably not have to inform the Local Authority for replacement of broken parts or sections of sewage as permission will have already been granted for the initial installation.
Surface water is basically water from rain and is handled differently from dark waste water in a modern sewage development. It can drain out through a soakaway, watercourse, surface water sewer or, especially in older houses, into the dirty water drainage pipes. The rainwater pipes in combined drainage systems empty their discharge into the foul water drains through gully traps, this prevent foul air from escaping outside creating odours. However with the new drainage systems, the foul and the surface water can be kept apart. It is extremely important to ensure that you do not connect foul water to a surface water sewage system. If you have doubts about your house’s sewage system, you can get help from the Building Control Department before you begin any work.
The first thing to do in a DIY sewage replacement job is to decide the position and level of the waste pipework. Keeping the path as straight and short as possible will be the main concept behind the design of the waste passageways or pipes. Steep pipes should be averted during the path design. Use a surveyor’s leveling tool to set out the slope of the drain trench. A hosepipe filled with water from an established datum point can be used if you don’t have a surveyor’s site level.
The stability of the existing building is of prime importance it should be not compromised while the drain pipe ditch is being installed so check you are not impacting on the existing structure. Similarly, take care of the substructures when laying a waste pipe that runs alongside the building.
If you try to dig all the trenches before you start pipe fixing, there is a chance of some trenches collapsing. Make certain that the pipes are laid as soon as possible and then bury them immediately after the testing and inspection are completed.
Weak soil may require that you shore up the walls of the excavation, particularly for deeper trenches. It is no advisable to not take any risks. It is better to provide support to the trench walls than allowing the trench to collapse. Keep the ditch as narrow as you can but of course make sure that there is enough room to work in the trench including any plan, machinery or tools you require. Protruding stones or bricks should not be left in the base and it should be cleaned to provide a smooth, regular surface. If the exiting material is not suitable then you may need to import a suitable material for the base of the ditch.
Pipework must be uniformly supported by the soil bed, and not by stones or bricks haphazardly placed underneath the pipes. Such hard objects will cause the poorly supported pipe to bend or break and the joints will eventually fail. The base should be tightly packed in the appropriate manner with holes carved out to fit in the protruding pipe connections. A comprehensive support should be used for the whole of the pipe.
It is very important that the design of the drainage system should be constructed in such a way that all parts of the pipework are accessible to a set of drain rods for future maintenance. Therefore, a run of drains should be as straight as possible between two points. Always make sure that rodding access is allowed in an inspection chamber at any point where the direction of the pipework changes.
DIY plumbing and drainage is certainly within the limits of most DIY enthusiasts.