Kitchen Vent Options

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Scott Yackley, Sep 1, 2021.

  1. Scott Yackley

    Scott Yackley New Member

    Joined:
    Jul 13, 2020
    Location:
    48383
    See attached layout. A local plumber recommended venting this kitchen sink with an AAV (Air Admittance Valve), but I am not that familiar with these devices. I was going to tie it into the main stack vent to only have a single cutout in the roof, but this has a long up and down path thru the attic. Another option is a separate stack on its own, but this would be towards the front of the house which I want to avoid if possible. Any thoughts on this?

    Thanks,

    Scott
     

    Attached Files:

  2. Terry

    Terry Administrator Staff Member

    Joined:
    Aug 17, 2004
    Occupation:
    Plumber
    Location:
    Bothell, Washington
    I have always had three or more vents through the roof. I've also not been allowed to angle up and then down with my vent.
     
  3. Sponsor

    Sponsor Paid Advertisement

     
  4. wwhitney

    wwhitney Well-Known Member

    Joined:
    Mar 17, 2019
    Location:
    Berkeley, CA
    That seems to be a difference between the UPC and the IPC. The UPC says ". . . vent shall be level or shall be so graded and connected as to drip back by gravity to the drainage pipe it serves." Which wouldn't allow the up and then down.

    https://up.codes/viewer/california/ca-plumbing-code-2019/chapter/9/vents#905.0

    But the IPC says "Vent and branch vent pipes shall be so graded and connected as to drain back to the drainage pipe by gravity." [Which precludes any level sections.] Since it doesn't specify the drainage pipe served by the vent, one can argue that the up and down is allowed, as each side connects to a vent that drains back to a drainage pipe.

    https://up.codes/viewer/colorado/ipc-2018/chapter/9/vents#905.2

    Cheers, Wayne
     
  5. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    no up and down with vents. easiest is the aav im not googleing your zip code and guessing your plumbing code to know if its allowed.
    so run a new stack or run aav.
     
  6. John Gayewski

    John Gayewski In the Trades

    Joined:
    Aug 7, 2021
    Location:
    Iowa
    Upc doesn't allow aav's. Being that your plumber advised you to use an aav I'm going to say your ipc.

    To me this looks like an enlarged island vent. I don't think any inspector would disallow any option other than the aav (in the case of upc).

    I would go with the individual stack mainly becuse it's easier than running all of that pipe through the attic in my opinion. Plus it's more sound and less likley to give you any differential pressure.
     
  7. Scott Yackley

    Scott Yackley New Member

    Joined:
    Jul 13, 2020
    Location:
    48383
    Yes, in Michigan which is IPC.
     
  8. Reach4

    Reach4 Well-Known Member

    Joined:
    Sep 25, 2013
    Location:
    IL
  9. James23912

    James23912 Member

    Joined:
    May 16, 2020
    Location:
    Vermont
    Could you run it along the attic floor to the smaller rear vent, giving a slight rise? Or using option 3, instead of going down, run it thru the roof near the peak on the back?
     
  10. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    I'm not a fan of AAV but I'm guessing there are literally millions in use and its legal there . but if all your walls are open and you haven't got a roof on just run a vent up and through roof its easy right?
     
  11. Scott Yackley

    Scott Yackley New Member

    Joined:
    Jul 13, 2020
    Location:
    48383
    Thanks for all of the feedback. Thinking will add this vent thru the roof so it is done right and don't have to worry about a mechanical device (AAV) failing down the road.
     
    Jeff H Young likes this.
  12. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    yea that is best , especialy if dosent require ripping open a lot of walls
     
  13. Reach4

    Reach4 Well-Known Member

    Joined:
    Sep 25, 2013
    Location:
    IL
    Why not the inverted V? Are you thinking it is against your code, or you suspect it will not work well?

    If you do go through the roof, you will probably involve a roofer. Plumbing vent flashing is like a special shingle.
     
  14. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    Maybe its not roofed or he is re roofing soon
     
  15. DIYorBust

    DIYorBust Active Member

    Joined:
    Mar 5, 2019
    Location:
    Long Island, New York
    I have read, possibly on this forum, that an up and then down vent pattern can cause the accumulation of lighter than air gasses at the top, methane perhaps? Can you vent it near the top and lower one branch?
     
Similar Threads: Kitchen Vent
Forum Title Date
Plumbing Forum, Professional & DIY Advice DWV - Can I drain my upper floor 2" kitchen sink into my basement 2" toilet vent Nov 7, 2021
Plumbing Forum, Professional & DIY Advice Best method for plumbing kitchen island vent Jun 16, 2021
Plumbing Forum, Professional & DIY Advice Another kitchen sink vent question -vent size Apr 3, 2021
Plumbing Forum, Professional & DIY Advice Moving kitchen sink -venting question Mar 29, 2021
Plumbing Forum, Professional & DIY Advice Bath, kitchen sink, venting question (yes, another one)! Feb 12, 2021

Share This Page