Underground Drainage

In this section, you will find all of our standard 110mm & 160mm PVC underground drainage systems - these are popular products that are used in everyday drainage projects including our underground drainage pipes. We offer single or bulk purchase options - our bulk purchases page below is ideal for buying materials for a whole site or project. You can also buy subfloor ventilation products in this section.

All of our underground drainage pipes and the majority of our fittings are manufactured from UPVC, and all pipe, bends, gullies and connectors in drainage systems are commonly manufactured in a Golden Brown colour.

Types of Drainage Systems

As well as the 110mm and 160mm pipes and fittings we also stock:

  • Rainwater harvesting systems - for capturing and reusing rainwater for various purposes such as watering plants and washing vehicles
  • Channel drainage - slotted drains for use in draining stormwater from driveways and patios
  • Soakaway crates - a versatile product that can be used for many types of sustainable drainage applications including infiltration and attenuation
  • Twinwall drainage - large PVCU pipes that are commonly used for surface water applications
  • Sewage treatment plants - water cleaning tanks ideal for properties that are not connected to mains drainage.

Plastic Drainage Pipes

Our range of plastic drain pipes and fittings are manufactured to British Standards. While we stock standard 110mm and 160mm pipes we also have Twinwall Pipes in 150mm, 225mm, 300mm, 450mm and 600mm and a wide range of soil and waste pipes.

Most domestic drainage pipes are now made from plastic, or PVC-U to use the proper term. PVC-U pipes are lighter and easier to handle than traditional clay drains. Clay drainage is still used on some commercial installations. All our plastic drainage pipes can be connected to clay pipes using our flexible drainage couplings.

If you want to find out more about the different drainage fittings we offer then we have video product reviews on our drainage pipe bends, drainage pipe junctions and drainage couplings


Our 110mm Drainage, which is the most common size for domestic drainage in the UK, is manufactured to BS-EN 1401 and BS 4660 and is compatible with the majority of inspection chambers.

All of our underground drainage pipes and the majority of our fittings are manufactured from UPVC, and all pipe, bends, gullies and connectors in the drainage system are commonly manufactured in a Golden Brown / Terracotta colour.


Our underground drainage products are fully compatible with our above ground soil and waste systems.

In this section, you will find all of the most commonly used drainage bends and different types of connectors and adaptors along with gully traps and other basic components of the drainage system. This system is interchangeable with all other leading manufacturers 110mm and 160mm systems.

What is underground drainage?

Underground drainage is the general term given to the system of pipes and fittings that are installed below ground level to transport foul drainage or rainwater flows to a sewage treatment facility or, in the case of rainwater, a soakaway or watercourse.

Most underground drainage systems today are manufactured in PVC-u, which is hardwearing and virtually maintenance-free. The smooth inner wall of the pipe also promotes a much better flow when compared to traditional materials.

Underground drainage pipes and fittings are almost always terracotta orange in colour. This makes identification easy, as soil pipes installed above ground level are usually black, grey or white.

How do you install underground drainage?

Underground drainage pipes are usually laid in a trench that has been lined with a bed of pea shingle. The installation must be laid to the correct fall and should always follow the basic drainage design principle that all points in the drainage system should be accessible for testing, inspecting and cleaning.

It is always a good idea to plan all drainage installations – most building projects in the UK will include a drainage layout drawing that has been designed by the architect. The key components in terms of design location are generally gullies, inspection chambers, rodding eyes and rainwater adaptors.

Cutting & Joining Drainage Pipes

One of the major advantages of plastic drainage pipes is that they are much easier to cut and join than clay pipes.

Pipes can be cut with a standard fine-toothed saw. Whenever a pipe is cut the end should be chamfered and cleaned. The chamfered end of the pipe and the ring seal of the fitting should then be lubricated before the pipe is firmly pushed into the socket and then withdrawn 10mm (this allows for expansion and ground movement). The joint is then complete.

To learn more about underground drainage installation, please watch our detailed video on the subject.

How Long Do PVC Drain Pipes Last Underground?

Whilst this depends on the exact composition of the surrounding soil, any PVC underground drainage pipe manufactured to BS4660 or BS EN 1401 should last more than 50 years.

The life of any drainage system will be prolonged by a good installation and maintenance when required – slow flows, gurgling sounds from the sink, bath or shower or foul odours in the house or garden are all symptomatic of a blocked drain and should be investigated as soon as they occur.

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