(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 5 of 5

Thread: Where to put the AAV

  1. #1

    Default Where to put the AAV

    Hello Everyone,
    I am finnishing off my basement and have all of the permits but after talking to the plumbing inspector I am confused. I will be adding a toilet, shower and sink. Does the AAV need to be at the end of the line or can it be at the sink, between the shower and toilet? I know I need to break out the concrete floor and also install a backflow valve. Any recommendations on the backflow (sanitary) valve? I have worked for water departments for 20 yrs, so I do understand a little about this. Thanks for your help!


  2. #2
    DIY Senior Member e-plumber's Avatar
    Join Date
    Sep 2004
    New York

    Lightbulb AAV Location

    Each fixture is supposed to be individually vented.
    Talk to the inspector again and find out how the code is written concerning vents, why do the work twice?

  3. #3
    Plumber, Contractor, Attorney LonnythePlumber's Avatar
    Join Date
    Sep 2004
    Wichita, Kansas

    Default No AAV

    I would be disappointed if your inspector has told you to use an AAV instead of real vents. The inspectors professional group has recently come out with their own code book called the International Plumbing Code that does allow AAV's. I would be interested to know where you live.
    Your backflow valve will have to have an access cover. If you can locate it someplace where you are not going to finish the floor it would be better. It will need to only serve your basement fixtures so it has to be installed before you tie in to your house drain.

  4. #4


    I live in the Flint area of MI. Can you recommend a brand of backflow valve as I am having a hard time finding anyone who has one or knows where to get one. It seems to me that it should not be this hard to find one since it is a building code requirement.

  5. #5
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Cave Creek, Arizona

    Default aav

    Any system that uses an AAV has to be an open system, meaning that somewhere there has to be a vent that is open to the atmosphere, usually out of the roof. In your case it would have to be on the toilet's side of the backwater valve. And you do not want the entire house running through the backwater valve if you can avoid it.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts