air admittance valve on soil pipe

[stanna]

Hi Fellas

Doing a bathroom and currently the pan is coonected to the soil stack whic runs internally at the side of cistern. The stack runs right into the ceiling and terminates in the loft. This leaves an ugly bit of boxing in that needs removing.

Can i chop of soil pipe and fit a air admittance valve just above level of water in cistern which can then all be hidden behind new boxing in of hidden cistern?

Cheers.

 

[spraggo]

Yes, but make sure that the boxing is not air tight.

 

[doitall]

Thought you could only have an auto air admittance valve, on a second stack.