House venting

Pottles · Post: # 91840Post **Pottles** Sat Jul 27, 2013 12:20 pm

If you are constructing five detached properties served by the same foul private drainage network do you only need to install a soil and vent pipe which penetrates the roof in the property at the head of the run?

Is there a maximum number of properties that can be served by a vent in the top property?

Thanks

Sat Jul 27, 2013 3:06 pm

IME its one vent per house
LLL

mickg · Post: # 91846Post **mickg** Sat Jul 27, 2013 5:10 pm

I agree every house has its own soil and vent pipe

Pottles · Post: # 91849Post **Pottles** Sat Jul 27, 2013 7:36 pm

Thanks for your help
So every house needs to have an open vent through the roof. Can you not install AAV,s in the other properties if they are connected to an external foul drain which is vented by the property at the head of the run.?

henpecked · Post: # 91850Post **henpecked** Sat Jul 27, 2013 7:39 pm

Its easier just to run one out of the top of the soil stack.

Mikey_C · Post: # 91853Post **Mikey_C** Sat Jul 27, 2013 9:49 pm

if it is the breaking through the roof, that causes you concern, put a valve at the top of each stack, as shown here

Sun Jul 28, 2013 12:17 am

Pottles wrote:Thanks for your help
So every house needs to have an open vent through the roof. Can you not install AAV,s in the other properties if they are connected to an external foul drain which is vented by the property at the head of the run.?

you need to be talking to your local BCO about this
IME its 1 per house ,but this can vary nationwide
cheers LLL

stephen gibson · Sun Aug 04, 2013 1:20 pm

I have just visited a similar estate where AAVs were fitted and the landlord has a years of complaints from tenants.

Key advice is in BS-EN12056-2 ND 3.5.7 Air admittance valves- which basically says that natural ventilation should be installed where reasonably practical. Only where termination of the stacks is difficult should AAVs be considered - say for example in a new internal bathroom where getting a natural vent to it could be very difficult.

I could imagine building control will not be convinced why in a new build standard ventilation is not easily possible.

See this link for more info on part h of the regulations http://www.wilsham.co.uk/building-regulations-part-h

I suggest you raise it with the engineer doing your above ground drainage design and calculations. So in summary - I wouldn't take the chance myself!