Connecting 40mm waste to 110mm soil stack

[Stuart22]

Hi,
I currently have an asbestos soil stack which runs through my kitchen!! I am looking to intsall a new stack outside the house. As part of this I am intending to connect the bath and basin waste to the soil stack outside.

Can anybody advise me which is the most reliable way to connect 40mm waste into 110mm? I have seen the bosses available but have read that they are prone to leaking. As its a new stack I can install any connections required.

Cheers,
Stu

 

[Nige F]

Strap on .. they can leak , and are for places where you have to put a connection onto an existing erected stack . New stack just buy boss pipes - should all be in any soil/ waste booklet . Wickes are a good DIY source. Better tell your local Building Control office . Because that new Outside stack is covered by Build, Regs

 

[Stuart22]

Yeah, I just love having the BCO round. Went ok last time but they charged me the earth for it!!!

Another probelm that i foresee is that the 40mm Waste and the 110mm soil will be exiting the house at around the same point which makes a near horizontal approach to the stack somewhat tricky......... any suggestions?

Also I wanted to stop the stack short of the roof line and use an air admittance valve. Are there any limitations on using them?

 

[omegaman]

Another probelm that i foresee is that the 40mm Waste and the 110mm soil will be exiting the house at around the same point which makes a near horizontal approach to the stack somewhat tricky......... any suggestions?

Can't you drop the 40mm pipe lower?

Also I wanted to stop the stack short of the roof line and use an air admittance valve. Are there any limitations on using them?

You can't use them outside. They could freeze in cold weather while closed.

And use glue!

 

[Richard C]

Yeah, I just love having the BCO round. Went ok last time but they charged me the earth for it!!!

That’s life; at least it was certified & you can produce a bit of paper to prove it when you come to sell; if not, it could cause trouble!

Another probelm that i foresee is that the 40mm Waste and the 110mm soil will be exiting the house at around the same point which makes a near horizontal approach to the stack somewhat tricky......... any suggestions?

Come on now; regulations aside, it’s at least got to flow downhill to work properly or your asking for trouble, is that why you don't want the BCO there!

Also I wanted to stop the stack short of the roof line and use an air admittance valve. Are there any limitations on using them?

Building Regs require you have at least one open vent on the foul drain system to cater for positive pressure; & contrary to omegaman’s post, you can get externally rated & approved AAAV’s

 

[omegaman]

[
Building Regs require you have at least one open vent on the foul drain system to cater for positive pressure; & contrary to omegaman’s post, you can get externally rated & approved AAAV’s

Not you again!

 

[Nige F]

Also I wanted to stop the stack short of the roof line and use an air admittance valve. Are there any limitations on using them?

any particular reason . I can`t find pictures of a stack on t`net maybe you could pick up a leaflet in Wickes or a Plumbers merchant.