Aav on vented soil pipe?

[mylocalplumber]

Hi All,

Quick question. Customer had en suite fitted with toilet soil pipe running out side of roof over guttering across about 6 m and teeing into existing soil stack on side of house. This then runs another 4-5 m into the vented pipe. All in all the en suite WC has a run of around 13 m. It also has an AAV where the WC is in the en suite.

My question: Is this AAV necessary when it is already vented or when having such long runs is it required or recommended?

plumbing a fair time and believe it or not, not do e much soil work.

All helpful replies thanked

Mo

 

[stevetheplumber]

yes its needed to allow air in due to the long runalternative would be to vent this run to atmosphere same as the main stack

 

[chris watkins]

yes its needed to allow air in due to the long runalternative would be to vent this run to atmosphere same as the main stack

From what I can make out steve from the OP that is what has been installed but it is difficult to work out if you have not seen the install, an chance of a pic or a diagram of the layout mylocal ??
If you have gone to all that work to connect the en-suit vent back into the main stack why would you add a "Durgo" I think Part H suggests that a WC float is limited to 6M if un-vented so maybe in has been added for this but then why bother to vent the new stack ?? Does sound like overkill.