What size air inlet valve (durgo)?

[Teachthomson]

Hi, we have had a downstairs toilet and utility room built and I need to plumb in the toilet including a Durgo. The branch has a toilet, 2 sinks, a washing machine and dishwasher running into it. What airflow would I need and does it need to be on a full 110mm pipe?
We have a dedicated 110mm pipe coming out of the ground to receive waste from 1 sink and install an air inlet. Was wondering if I can put a simple reduction on the pipe and put something like a 40mm vent on?

 

[king of pipes]

Any pictures of what you have ???

 

[WC1]

If you've a 110 pipe vertical why would you go the trouble of reducing it and then the small bore aav. Just shoving a 110 aav would take up less space esp one without a mushroom e.g. polypipe

POLYPIPE Soil and Vent 110mm Automatic Air Admittance Valve, Black, SPV110B

POLYPIPE Soil and Vent 110mm Automatic Air Admittance Valve, Black, SPV110B from Plumbing for Less, the one stop for plumbing needs. Buy Today.

www.google.com

 

[Teachthomson]

If you've a 110 pipe vertical why would you go the trouble of reducing it and then the small bore aav. Just shoving a 110 aav would take up less space esp one without a mushroom e.g. polypipe

POLYPIPE Soil and Vent 110mm Automatic Air Admittance Valve, Black, SPV110B

POLYPIPE Soil and Vent 110mm Automatic Air Admittance Valve, Black, SPV110B from Plumbing for Less, the one stop for plumbing needs. Buy Today.

www.google.com

Thanks for the reply, I didn't reduce just chopped a small chunk of the plaster board wall out to make enough room