Frequently Asked Questions
Stainless steel, PVC, HDPE, Clay, Cast iron and Copper have been used as drainage pipes for buildings. Clay, cast iron and copper are less popular, but PVC and HDPE are the most popular. Stainless steel is far the most durable for drainage pipes in buildings especially where chemicals in wastewater are involved
For more info, click here
All materials will either expand or contract with temperature and the coefficient of linear expansion characterises by how much. For example. For every metre of material and a one degree C of temperature change, stainless steel will expand (or contract) around 16.5 microns; concrete 12 microns (very similar to stainless steel); PVC 50 microns. If pipes are buried in concrete, you do not want excessive differential expansion taking place as this stresses the pipes and can cause failures.
For more info, click here
- Not rodent proof
- Fails when in contact with high temperature liquids.
- Toxic chemicals are emitted when PVC is burned
- Environmental issues with PVC production and disposal
- Coefficient of linear expansion is not similar to concrete: differential expansion stresses the pipe material and can cause failure
For more info, click here
- Very susceptible to thermal expansion
- Combustible
- Lengths of HDPE pipe are inexpensive, but fittings costly
- No scrap value
For more info, click here
- Similar coefficient of linear expansion to concrete
- Suited to high temperature applications
- Lightweight, strong, durable
- Excellent corrosion resistance characteristics
- Non-combustible
- Rodent-proof
- Can be recycled and has significant scrap value
For more info, click here
Drainage reticulation
- Straight pipes
- Bends
- Swept Bends
- Branches
- Transitional branches
Foul air movement
- P traps
- Vent cowls
Pipe joining
- Couplings
- Repair couplings
- Connectors
Speciality fittings
- Expansion sockets
- Socket plugs
- Access units
- Clamped plugs
For more info, click here
Watermark Level 2
For more info, click here
The following standards will assist designers select the correct size of pipe system for a particular application:
- EN 12056: Gravity Drainage Systems Inside Buildings.
- EN 752: Drain and Sewer Systems Outside Buildings.
For more info, click here
The choice of seal depends on the specifics of the application. Some factors to consider, chemical resistance, heat resistance, strength etc..
For more info, click here
The choice of diameter depends on the hydraulic requirements of the project including the gradients which the pipes are to be laid. Flow tables are available to assist with sizing.
For more info, click here
Depending on the problem, different cleaning agents are recommended.
For more info, click here
