Do I need an air admittance valve

[Michael1965]

Hi everyone,, I'm a keen DIYer and need some advice on AAV or durgo valve,, we're renovating our house and plan to put a bathroom on the other side of the house, we currently have an old stack going straight up through the roof which is open to vent naturally, we plan on putting another soil pipe down through the ceiling and joining in with the old system, the way it looks at the moment Is that we have no room to fit an AAV/durgo , do we really need one? Could I put vents on the bath and sink in stead of the toilet? Hope someone can help..

 

[Deleted member 120897]

Not if you’re joining up with the old one. I think similar would apply if you were putting up a new stack, providing the existing is ventilated.