WHB waste pipe length

[sdickie]

I am hoping to install a new WC suite in an understair cupoboard. However, the length of the waste from the WHB to the external soil stack will be approx 3m.

Is it possible to run a pipe this distance ? If it is how do I do it, i.e.

- what diameter of pipe
- gradient of fall
- is an air admittance valve required/where along the length is it installed

Thanks.

 

[Bahco]

Run it in 40 mm waste with a fall of 1 inch per metre.
No AAV needed up to 3 metres.

 

[bathjobby]

40mm for single basin should be fine, although regs say 50mm once beyond approx 2.4mtrs.

 

[sdickie]

Many thanks

 

[silverback]

Run it in 40 mm waste with a fall of 1 inch per metre.
No AAV needed up to 3 metres.

I find tha amusing, how can you mix Imperial and Metric measurements

 

[Nige F]

Quite easily...tho` it give a clue to one`s age Hectares Acres hundredweights tonnes tons..all done by rule of thumb here in the sticks.