(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 9 of 9

Thread: Minimum pipe size for a toilet vent?

  1. #1
    DIY Member lahabra's Avatar
    Join Date
    Dec 2007
    Location
    California
    Posts
    50

    Smile Minimum pipe size for a toilet vent?

    According to my hand book the minimum pipe size required to vent a toilet is:

    1.5”

    Or

    2” as a wet vent for a sink.

    Am I understanding this correct?

  2. #2

    Default

    What code are you using? UPC requires 2" for a toilet vent.

  3. #3
    DIY Member lahabra's Avatar
    Join Date
    Dec 2007
    Location
    California
    Posts
    50

    Smile Wet vent

    Ok so I need at least a 2” vent for my toilet.

    Can I also drain my sink into the same 2” pipe?

  4. #4

    Default

    I still don't know what code you're using, or how you're going about it.

  5. #5
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking It depends on your location

    It really depends on your local in the USA

    I get away with murder in INDIANA with our code....

    1 1/2 pvc is big enough for the whole house to be
    vented onhere....


    other parts of the country expect a full
    3 inch stack out hte roof..

  6. #6
    Forum Admin, Expert Plumber Terry's Avatar
    Join Date
    Aug 2004
    Location
    Bothell, Washington
    Posts
    14,202
    Blog Entries
    1

    Default

    With newer toilets that flush faster, you would want at least 2" on the vent.

    In some places you can wet vent a bathroom lav over a toilet, if that line is 2" or larger.
    A kitchen sink could not be wet vented.


  7. #7
    DIY Member lahabra's Avatar
    Join Date
    Dec 2007
    Location
    California
    Posts
    50

    Smile

    Quote Originally Posted by Herk View Post
    I still don't know what code you're using, .
    The book I am reading is a general construction book it covers everything from grading to roofing. The book dose not tell me specifically what size vent I will need for a toilet; however, it dose have tables soused from: "UBC Illustrated training manual (Walnut, calif: International association of plumbing and mechanical Officials 1985)."

    In one table I read that a private toilet counts for 4 fixture units. The next table shows 1.5" pipe being capable of venting 8 fixture units. Based on these two tables it appeared that 1.5" pipe could actually vent 2 toilets.

    In the houses I have worked on I always see 2" vent pipes for toilets, add to that your reaction and the fact that I don’t want to get into a challenge with my inspector, I am definitely not going to install a 1.5” vent on my toilet.

  8. #8
    DIY Member lahabra's Avatar
    Join Date
    Dec 2007
    Location
    California
    Posts
    50

    Smile acording to UPC 2006

    Thank you for the diagram Terry!

    In some places you can wet vent a bathroom lav over a toilet, if that line is 2" or larger.
    So It is ok to use a 2" pipe as a wet vent for a toilet and a bathroom lav. Would this setup be in compliance with: "UPC 2006"?

    It has been my experience that most cities in the LA basin don't make up plumbing codes; instead they simply adopt "UPC". But I will need to confirm it in my particular city.
    Last edited by Terry; 03-07-2011 at 02:38 PM.

  9. #9
    DIY Senior Member construct30's Avatar
    Join Date
    Jun 2007
    Location
    NorthWest PA
    Posts
    590

    Default

    I have the third edition of the code check plumbing for 2006, the little flip job books, it says the IRC does not require a vent on a water closet for residential. What's up with that?

Bookmarks

Posting Permissions

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