A common problem in plumbing remodeling is figuring out how to run new vent lines when access to the existing drain-waste-vent system is blocked by some structural element.
One option is an air admittance valve. These valves are gravity-operated devices that respond to the negative pressure of draining water and open to let air in. Then gravity closes the valve, keeping sewer gases out of the room. Depending on the valve and the size of the vent, AAVs can support one or multiple vent lines. Local codes govern the use of AAVs in place of vents.
Prestart Checklist
Time
About an hour to cut and assemble five or six pipes and fittings
Tools
PVC saw or backsaw, miter box or power miter saw, deburring tool, felt-tip marker
Skills
Cutting and measuring pipe, working methodically
Prep
Sketch drain/vent assembly; clear a path for the pipes
Materials
Primer and cement for your type and size of pipe, P-trap, air admittance valve, drain pipe
Making these dreams come true is simpler than you thought -- print these instructions to begin!
Can 1 AAV vent placed on a sink drainage line also serve a tub and toilet in a basement washroom?
12/19/2011 02:14:59 PM Report AbuseQuestion how do you connect to 1 1/4 inche pipes under bathroom sink? These are all made for 1 1/2 or larger.
12/11/2011 04:26:43 PM Report Abuse