Can AAV be installed for the whole drainage installation?

[estebanvmeo]

Hello, my question is:

I'm working in the refurbish of an old building. The existing drainage is not going to be retained, moreover, it was external, but not coming through the roof, was wall mounted.

I wouldn't like to do any hole in the roof. Could I use Air Admittance Valves for all the drainage installation instead to put the vent going through the roof?

Someone told me that you always have to put at least ONE stack ventilation pipe through the roof. I read many things, including Part H BR, but I couldn't find anything about it.

Do you know something about this??
Thanks in advance

 

[jeds]

You must have an open vent if the system connects to a sewer with an intercepting trap.

 

[estebanvmeo]

Thanks John.

So can I used them as a primary ventilation? I wouldn't mind to have one stack vent in the roof, but I wouldn't like to have No.10 :S

In the paragraphs 1.20, 1.33, A7 and A9 withing the Part H BR, don't say anything about not to use them as a primary ventilation or secondary. At least, I didn't understand it like this, I'm not sure.

Cheers

 

[jeds]

The key thing is the interceptor. If your sewer line is connected to, or is near to, an interceptor then you must have an open vent. Unfortunately the use of interceptors is very much a local thing. They are common in some places and not in others.

As far as I know if you don't have an interceptor you aren't forced to have an open vent - although you would need to demonstrate that the system is adequately ventilated and that might not be as easy as it sounds.