Soil Pipes and Waste Pipes

If you’re not a qualified plumber or in the drainage trade it’s unlikely that you’ve ever needed to know the differences between a soil pipe and a waste pipe – unfortunately the drainage industry can sometimes be hard to get your head around, after all, surely a pipe is a pipe?! Unfortunately not. 

Whilst both types of pipes do carry out the same purpose - transporting waste water away from your home to the main sewer network, there are a number of very crucial differences between the two.

See our helpful guide below…

What is Soil Pipe?

A soil pipe is just that, a pipe that is designed to carry soiled water away from your home, whether that be from your toilet, urinal or bidet.

Although it seems like any old pipe could hold and transport soiled water, soil pipes should be manufactured to the relevant British standard which is why at Drainage Online we only stock the leading manufacturers of soil pipe such as Brett Martin, Marley and of course, Hargreaves for those looking to keep it traditional with Cast Iron soil pipes. Stocked in 110mm and 160mm diameter, Soil Pipes are much wider than waste pipes.

Soil Pipes need to be vented (generally at the top or very near to the top of building) to allow for the safe disposal of gases and to reduce odours and ensure that the pipes are creating a safe area – often gases from soil pipes can be harmful to health (but not always) which is why it’s best to ventilate the pipes as high as possible.

Vent pipes and outlets are an important part of any soil waste system, not only do they ventilate the systems but they also regulate pressure ensuring the positive pressure does not (in extreme cases) push waste water back to your sink, or worse toilet – vent pipes help to regulate this pressure!

Soil Pipes

What is a Waste Pipe?

A uPVC waste pipe carries water from things you use each day such as your shower, sinks, dishwasher and washing machine, similarly to soil pipes in that they are directing the waste water away from your home.

Manufactured by one of the market leaders, Brett Martin, to BS5255 all our waste pipes are compatible with all other leading waste pipe manufacturers. Our range of waste pipes range in diameter from 32mm to 50mm as they are only required to carry water, not waste. Therefore, they are also not required to be vented high above ground level. 

Push-fit waste pipes are becoming increasingly popular with installers and DIY’ers, they are easy to install, feature a ring seal joints to ensure a water-tight fitting and like, the solvent-weld range accommodate for thermal movement.



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Should you need more information or advice about which pipe to choose for your drainage requirements, simply call us on 01254 286083 or email us at and one of our experts will get back to you!