Air Admittance Valve (Soil Pipe)

[ln1234]

For a horizontal run of soil pipe connected to 2 ensuite toilets + wastes for Shower/Sinks, where would you place the air admittance valve? i.e. at the furthest end or closer to the soil stack?

Rough diagram:


S ||==========TOILET==TOILET==VALVE?
T ||
A ||
C ||
K ||

I understand that without the valve, the 2nd toilet, sink or shower tray may make gurgling noises when the first one is flushed? Are there any other considerations when installing pipework like this?

thanks

 

[ChrisR]

WHy can't the stack go on up - you'd be best off with a vent to let pong out?

 

[supermario]

the toilets are unlikely to suffer induced siphonage to the extent of loss of seal because their outlet to ths stack rarely runs full of water. As for wash basins you can get bottle traps with integral air admittance valves. if you want to put air admittance valves in the discharge pipe work to be effective they need to be in the areas of reduced air pressure ie between traps on the same discharge pipe[/quote]