Discover everything you should know about air admittance valves (AAVs) and how you can install one yourself to save time and money.
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. It may seem like all hope is lost, but don't let that small roadblock get in the way of your dream kitchen makeover. One solution is an air admittance valve, or AAV, and we've got all you need to know to install one yourself.
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.