G
geriatrix
My son has bought a house which has a rear single storey extension. The soil pipe from the loo etc rises to just the height of the eaves of the extension and stops. This looks like bad news, and is probably illegal.
His plumber suggested fitting am air admittance valve to the top of it, but I thought these could only be used internally because of the possibility of freezing.
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Not really sure what to do. Is there a filter or something that can be attached to the top instead of a valve, or would it be permissible to make a right angle to take pipe over the extension roof, and then another right angle to take it up to the required height on the main building.
Thanks for any suggestions - looks like he's bought a whole load of trouble......
DaviD J
His plumber suggested fitting am air admittance valve to the top of it, but I thought these could only be used internally because of the possibility of freezing.

Not really sure what to do. Is there a filter or something that can be attached to the top instead of a valve, or would it be permissible to make a right angle to take pipe over the extension roof, and then another right angle to take it up to the required height on the main building.
Thanks for any suggestions - looks like he's bought a whole load of trouble......
DaviD J