Toilet vent advice

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by mmax, Aug 15, 2021.

  1. mmax

    mmax New Member

    Jul 26, 2010
    I am roughing in for a new 1/2 bathroom and am having trouble with venting the toilet. See the attached photo. The vent for this bathroom and a laundry room above is to the left of the toilet. I would like to have the closet bend go to the right under the toilet to stay in the joist bay all the way to the basement wall below where it will turn and connect to the stack. I can go out the back of the toilet and vent up the wall behind the toilet, but I would 1) like to avoid cutting through the joist, and 2) there is currently an HVAC supply duct filling up most of that joist bay.

    Is there another way I can make this work? I am under the 2018 UPC. And advice is appreciated. Thanks

  2. wwhitney

    wwhitney Well-Known Member

    Mar 17, 2019
    Berkeley, CA
    Yes, you can wet vent the toilet using the sink drain by sending it into the joist bay with the toilet fixture drain and connecting them with a horizontal wye.

    Which plumbing code are you under? If it's the UPC, then the sink drain and vent would need to be upsized to 2" (the trap arm can be 1.5"). If you are under the IPC, then it can all be 1.5".

    Cheers, Wayne
  3. Sponsor

    Sponsor Paid Advertisement

  4. Jeff H Young

    Jeff H Young In the Trades

    Feb 27, 2020
    UPC 2 inch just put a combi on the 3 inch line to the w/c and run to your lav and vent 2 inch the whole way
Similar Threads: Toilet vent
Forum Title Date
Plumbing Forum, Professional & DIY Advice Toilet Venting Nov 22, 2021
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 Venting toilet using elbow w/ low heel inlet Oct 21, 2021
Plumbing Forum, Professional & DIY Advice Why vent toilet through sink? Oct 19, 2021
Plumbing Forum, Professional & DIY Advice Toilet & Shower Venting Oct 8, 2021

Share This Page