do i need to fit air admittance valves All aspects of plumbing questions and answers, help, tips and information

[chocco]

hi can anyone help i have run new underground drainage with new acees chamber and have run 2 new pipes into access chamber for 2 new toilets do both pipes have to be vented and can both if needed be fitted with air admittance valves so i dont have to come through roof
thanks chocco

[bobplum]

id say on balance yes
two pipes two valves#bob

[marrtin]

It is normal only to fit one air admittance valve on the toilet which is on the end of the main sewer run. So generally, each property is required to fit one vent stack regardless of how many toilets are fitted.

[chocco]

is this the case even if i have sewer runs going into access chamber
regrds dave

[bobplum]

id say it depends on wether you run the two waste outlets from each toilet into one soil pipe or if you intend to run each waste outlet into the sewars direct
one soil pipe one vent
two individual soil pipes then two vents
bob

[chocco]

[quote="bobplum"]id say it depends on wether you run the two waste outlets from each toilet into one soil pipe or if you intend to run each waste outlet into the sewars direct
one soil pipe one vent
two individual soil pipes then two vents
bob[/quote]thanks bob i am running 2 soil pipes so will fit 2 admittance valves