Length of waste pipes

[astroman]

Hi all,

Can you advise please?

I am installing an en-suite bathroom. I intend to use 40mm waste pipes from the basin & bath/shower, Is there any regulations concering the maximum run of an internal waste pipe or soil pipe?

Thanks

Chris

 

[Bahco]

32mm =1.7 metres
40mm =3.0 metres

If you are going straight into the stack you need anti vac traps.

You can extend these runs if you protect with AAVs

 

[bathjobby]

I thought 40mm was 2mtrs but I'll take your word Bacho. Anyhow, (2 or 3) is your running longer than that you should go to 50mm.

 

[chrishutt]

If you are going straight into the stack you need anti vac traps

Why?

For regulations try this.

 

[Bahco]

Good link Chris.

I have been told that going straight into the stack could lead to loss of trap seal and is always best to allow air in.

I'll take your word for it.

 

[chrishutt]

My understanding is that anti-vacuum traps would be required if the normal limits on branch length and gradient could not be met, or if more than one appliance was connected to a waste pipe. In general any situation where syphonage (self or induced) would otherwise occur.