Underground Drainage
Pipes, fittings and manhole inspection chamber parts for plastic PVC-u terracotta 110mm underground drainage, as commonly used in residential development.
Lightweight and impact resistant solid walled plastic terracotta 110mm underground drainage pipes. Available with socketed end, or pre-chamfered plain end for insert into socket fittings.
Key Features

A full waste management system.
We sell an extensive range of guttering, downpipe, soil and waste management systems for domestic, commercial and industrial applications. They are registered in England and achieve some of the highest business management standards(ISO 9901, ISO 14001, OHSAS 18001, ISO 50001).
Part of our range of durable and impact resistant fittings for plastic PVC-u underground drainage pipes, the most common residential system. These lightweight, easy-fit parts are compatible with all systems manufactured to BS EN 1401 or BS EN 13476-2.
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Underground Rodding Eye
Regular price £2.36Regular priceUnit price per -
Underground Bottle Gulley Grid
Regular price £1.20Regular priceUnit price per -
Underground Rubber Rainwater Adaptor
Regular price £8.89Regular priceUnit price per -
Underground Round to Square Grid Adaptor
Regular price £1.93Regular priceUnit price per -
Underground Slip Coupler (Double Socket)
Regular price £2.80Regular priceUnit price per -
Underground 90° Junction (Triple Socket with Twin Boss)
Regular price £8.98Regular priceUnit price per -
Underground 45° Bend (Double Socket)
Regular price £4.16Regular priceUnit price per -
Underground 110mm Pipe (3m)
Regular price From £14.94Regular priceUnit price per -
Underground Socket Plug
Regular price £3.62Regular priceUnit price per -
Underground Gulley Raising Piece
Regular price £9.32Regular priceUnit price per -
Underground Bottle Gulley (Rear Inlet)
Regular price £16.58Regular priceUnit price per -
Underground 90° Junction (Double Socket with Twin Boss)
Regular price £9.36Regular priceUnit price per -
Underground 30° Bend (Double Socket)
Regular price £3.66Regular priceUnit price per -
Underground Square Hopper Grid
Regular price £2.45Regular priceUnit price per -
Underground Straight Rubber Coupler
Regular price £14.63Regular priceUnit price per -
Underground Square Hopper
Regular price £11.78Regular priceUnit price per
FAQ
What is the difference between a soil pipe and a waste pipe?
Soil pipes carry soiled water (blackwater) from toilets, urinals, or bidets, while waste pipes transport wastewater (greywater) from sinks, showers, baths, and washing machines to the main sewer or a treatment facility.
What size soil and waste pipes do I need?
Soil Pipes: 110mm diameter for toilets, urinals, bidets, and soil stacks.
Waste Pipes: 32mm for small hand basins; 40mm for sinks, showers, baths, washing machines, and dishwashers; 50mm for commercial applications or connecting multiple waste pipes.
Soil pipes are larger to accommodate solids, whereas waste pipes handle only liquids.
What is a soil stack?
A soil stack is a vertical 110mm soil pipe that connects interior soil and waste pipes, directing waste to the main sewer or an off-mains system. It often extends above the roofline to vent gases and balance air pressure.
What is the difference between a soil stack and a waste stack?
A waste stack is a vertical pipe (typically 50mm) that collects discharge from sinks, showers, and similar appliances. A soil stack serves the same purpose for toilets and similar fixtures. In many properties, both systems connect to a single vertical pipe.
What is a soil vent pipe?
A soil vent pipe (SVP) is a segment of the soil stack that extends above the roofline, allowing harmful sewer gases to vent safely into the atmosphere and helping to balance air pressure within the system.
What is an air admittance valve?
An air admittance valve (AAV) is a one-way mechanical valve that permits air to enter the soil and waste system to maintain atmospheric pressure while preventing the escape of foul gases.
What is the difference between a soil vent pipe and an air admittance valve?
Both devices help balance pressure in soil and waste systems. However, a soil vent pipe releases sewer gases into the atmosphere, whereas an air admittance valve allows air in but does not let gases escape.
Is push-fit better than solvent weld for waste pipes?
Push-fit systems are quicker and easier to install, ideal for DIY projects. Solvent weld systems create a permanent bond, offering durability and leak resistance, making them suitable for long-term installations.
Can you connect waste pipes to a soil stack?
Yes, waste pipes can be connected to a soil stack using appropriate boss adaptors, regardless of the connection type or material of the soil stack.
Do waste pipes need to be connected to a soil stack?
Not necessarily. Waste pipes can connect directly to the main drain. However, systems not connected to a soil stack may require an air admittance valve to prevent negative pressure and ensure proper drainage.