soil ventilation

[calvert]

All the waste from my house feeds into a modern septic tank via internal soil pipes (including kitchen sink) so the only ventilation of the system is by 2 air admittance valves on stub-stack pipes. Is this ok or should I extend a stack pipe to vent to fresh air outside? The air admittance valve has a warning that it should not be used at the head of the system.

 

[doitall]

At least the head of the drain should go to atmosphere.

 

[Nige F]

All the waste from my house feeds into a modern septic tank via internal soil pipes (including kitchen sink) so the only ventilation of the system is by 2 air admittance valves on stub-stack pipes. Is this ok .....NO>>>>>>>or should I extend a stack pipe to vent to fresh air outside?YES......... The air admittance valve has a warning that it should not be used at the head of the system.

Who fitted the drainage and ignored/didn`t know these basic principles

 

[calvert]

Thanks very much for the answers. As to who did the job, lets just say we already parted company!