toilet rough in

Discussion in 'Toilet Forum discussions' started by Andrew M, Apr 15, 2007.

  1. Andrew M

    Andrew M New Member

    Joined:
    Feb 17, 2007
    I am a newbi so bear with me. 2 questions. I am building a new bath from scratch. What size hole do I need in the floor for the toilet ABS ? Second question is more difficult. I have hear people talk about the risk of "Siphon effect" if my vent pipes are not installed exactly correct. Can someone expand on this?
     
  2. jimbo

    jimbo Plumber

    Joined:
    Aug 31, 2004
    Location:
    San Diego, CA
    The purpose of the vent on each plumbing fixture is so that a local vacuum does not develop, which would siphon the water out of the trap. The trap is to keep sewer gas out of the house.
     
  3. Sponsor

    Sponsor Paid Advertisement

     
  4. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    The size hole to leave for a toilet drain is a little subjective. Depends on the type of flange you use and the height of the finished floor and the size of the drain line (3" minimum, 4" typically max). If you use a 4" line, you can butt the flooring up to it directly, since you can buy a flange that will fit inside of the 4" pipe. If you go with 3", then you need enough room outside of the pipe for the taperd part and the thickness of the flange. So, it's hard to give an exact amount.
     
Similar Threads: toilet rough
Forum Title Date
Toilet Forum discussions Recommendations for 10" Rough-In Toilet Friday at 9:22 AM
Toilet Forum discussions Moving toilet rough-in Sep 11, 2017
Toilet Forum discussions Watch a rat wriggle through a toilet Aug 26, 2017
Toilet Forum discussions Need Toilet to Fit 13 Inch Rough In May 20, 2017
Toilet Forum discussions Need a toilet for 12" Rough in with 4 3/8" pipe boxing Apr 20, 2017

Share This Page