soil pipe (air admittance valve)

[Montycaboodle]

Hi Everybody (Monty's back)

I recently had a post titled "Flashing around a soil pipe" and i had a very good response to which i am very greatful.
I am builiding a lean-to, problem is a soil pipe will have to go through the polycarbonate roof, the replies i had was to use a WEATHERING SLATE, fantastic this would solve my problem.I was informed by a builder that i could fit an "AIR ADMITTANCE VALVE" therefore i would not have to go through the roof as this valve allows air into the pipe work without any foul gasses escaping into the lean-to.
What i would like to know is this legal and if it is do, they WORK

 

[kevplumb]

its letting the air in without the pong escaping

theory what have you s** it change the durgo

 

[Montycaboodle]

Thanks Kev
I know it lets air in and not suppose to let pongs in,but do they work,and are they legal indoors.

Monty

 

[Mr Winston]

They can only be used indoors as if used outside the valve freezes and it wont work.

The 'pong' is largely methane gas - not nice stuff.

An air admittance valve (AAV) can only be used if it is connected to a ventilated drain - (if you have another soil stack which is ventilated to outside air this may be okay providing the length of the pipe run from the new stack to the ventilated drain is 6metres or less).

Otherwise the methane gas will build up and explode your street!!!!!

 

[Montycaboodle]

Thank you Mr Winston
I am now in the picture, looks like i will be using a Weathering slate afterall as i have only one soil pipe.
Many thanks again.
Monty

 

[Freddie]

They can only be used indoors as if used outside the valve freezes and it wont work.

The 'pong' is largely methane gas - not nice stuff.

An air admittance valve (AAV) can only be used if it is connected to a ventilated drain - (if you have another soil stack which is ventilated to outside air this may be okay providing the length of the pipe run from the new stack to the ventilated drain is 6metres or less).

Otherwise the methane gas will build up and explode your street!!!!!

It is NOT methane gas--methane gas has no smell.

The smell is Hydrogen Sulphide and is heavier than air.

 

[Mr Winston]

I did say 'largely' - not solely - methane gas makes up a significant portion of the toilet pong gas along with nitrogen, oxygen, carbon dioxide, hydrogen and other gases.

No gas should come through an aav as it dosent release it only admits