Inside fit closet flange 3"

Discussion in 'Toilet Forum discussions' started by dradam, Sep 21, 2008.

  1. dradam

    dradam New Member

    Messages:
    22
    Location:
    Washington
    My contractor left me with a 3" wc pvc rough in. The pvc pipe comes straight out of the cement slab and no space was left for an over the pipe closet flange.

    While inside the pipe 3" closet flanges are available people seem to discourage these because of the narrower diameter (2 11/16). I was ready to take out the cement chisel but noted that the wax ring plastic flange that came with the toilet ( Kholer memoirs all in one box including the wax ring) had the same 2 11/16 (maybe 2 3/4) diameter as the inside fit closet flange.

    If the plastic flange that came with the toilet maches the inside diameter of the inside fit 3" pvc closent flange shouldn't that work? if I used a bigger closet flange that left a 3" inner diameter wouldn't the wax ring flange still restrict the flow any way? If I change to a wider wax ring the toilet outflow hole is the same diameter anyway.

    thanks
  2. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,329
    Location:
    Yakima WA
    First thing to do is throw that wax ring with the plastic flange as far as you can. These cause problems and do no good whatsoever. Next thing to do is throw that inside fit flange the other direction so that the two will never meet. You indicate that you know these are not recommended because they cut the inside diameter of the pipe too much. Now get the flange that fit on the outside of the pipe, chip out enough concrete to allow the flange to fit over the pipe. Make sure the flange rests on top off the finished floor...NOT the sub floor. Anchor the flange to through the finished floor and into the sub floor. When you are ready to install the toilet, use a conventional wax ring. All of those things you threw away are gimmicks and are never used by professional plumbers. Just because they are sold, doesn't mean they are any good.
  3. Redwood

    Redwood Master Plumber

    Messages:
    7,453
    Location:
    Connecticut
    The only thing I could add to Gary's excellent answer is to get a flange that has a stainless steel ring and not to use an all PVC flange or, a painted steel ringed one.

    It goes on top of the finished floor too!
  4. Basement_Lurker

    Basement_Lurker One who lurks

    Messages:
    668
    Location:
    Victoria, BC
    If you look at the trap specs of most toilets, the internal trapway is only usually about 2"-2.5" (roughly) in diameter, and the trap seal is only about 2.5" (roughly) in diameter. So by the numbers, using an inside fit flange shouldn't really cause any constriction problems.

    I suppose the problem arises with the fact that some toilets can have a bit of play when installing them as far as centering them on the flange hole (shit-hole) which could result in a possible constriction when installed on an inside fit flange.

    I would guess that using a 3" inside fit flange is probably against code in some/all states. But since your contractor left you to finish the job, I guess you have to make the decision on what's the best thing to do. Chiseling around the pipe and installing an outside fit 3" flange is the standard proper method, but using an inside fit flange so long as you take care to center the toilet on the bolts could also work (although I am sure that suggestion is going to enrage some of the mods here, heh).
  5. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,896
    Location:
    New England
    Some (albeit small number of) toilets have larger trapways (I think the Caroma is one at 3"). Using an internal mount flange limits your options and could block some things that might have made it through the smooth trap of the toilet and catch on an edge of the possibly smaller flange. You really don't want to do this. When the wax smushes down, it's possible some of it would also go in.

    If you use a wax ring with a horn, you won't get a seal, since that horn WON'T fit inside that small opening, creating the very leaks it is supposed to prevent. It sometimes has troubles even on larger flanges, especially if things aren't perfectly centere - basically, they're more trouble than they're worth and cost more, too.
  6. kingsotall

    kingsotall Plunger/TurdPuncher

    horny wax rings

    Kohler likes to include them with their toilets.
  7. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,329
    Location:
    Yakima WA
    Many Toto toilets have 3" trap ways. Basement Lurker, I'm not enraged, but I certainly take exception to your opinion on the inside flange on a 3" pipe. The fact that Kohler includes them and by implication recommends them, hardly gives me a warm fuzzy feeling. Kohler reputation for quality products has gone down the toilet (pun intended) especially since low flow toilets have become mandated. As Jadnausha states, the horn causes more harm than good. In fact, it does no good.
  8. Basement_Lurker

    Basement_Lurker One who lurks

    Messages:
    668
    Location:
    Victoria, BC
    Gary, are you sure about most TOTO's having 3" trapways? I haven't seen one yet, and not even the highly rated AQUIA models have a 3" trapway (or so say the spec sheets).

    Are you confusing the actual trapway sizing with the 3" flush valves that TOTOs use, or am I the one who is confused about the unifit flange diameter?
  9. dradam

    dradam New Member

    Messages:
    22
    Location:
    Washington
    what I figured you'd say

    Thank you guys all--

    It sounds like whipping out the chisel is the safest long term option and a better wax ring.

    advice most appreciated.
  10. Redwood

    Redwood Master Plumber

    Messages:
    7,453
    Location:
    Connecticut
    Your on the "right" road to take it to the outside...:D
  11. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    I think lurker is correct about the trapways. 3" + on the flushvalves is common, but I seem to remember the trapways being listed as more like 2½"
  12. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,488
    Location:
    Cave Creek, Arizona
    flange

    This may be a case where logic does not work. EVERY plumber, if he has been doing repair work for any length of time, has encountered leaking toilets where the only possible cause would be the wax ring with the funnel. The funnel will cause splashing up against the bowl and if the wax ring has a marginal seal, possibly because the bowl rocks, that can cause the leak.
  13. masterbath

    masterbath New Member

    Messages:
    16
    dang i used the wax ring that came with my memoirs toilet. maybe they used a different wax ring for yours but my Kohler memoirs came with this one and you see the measurements.

    http://www.terrylove.com/forums/showthread.php?t=23509

    had i known i would have used a wax ring without the plastic insert but i thought that was just a recommendation of when using the inside 3". i have always worried about those things sliding off center when mounting the toilet only to cause issues later.
  14. Redwood

    Redwood Master Plumber

    Messages:
    7,453
    Location:
    Connecticut
    The Toto Drake has an O.D. measurement of 2 7/8" on the outlet horn combine this with a inside 3" flange and a wax ring with a plastic horn and I can guarantee results that will be far from pleasing!

    No rocket science involved!
  15. masterbath

    masterbath New Member

    Messages:
    16
    i'd also like to point out that while i am happy to have a toilet, i am not too impressed with the holer memoirs. loud and gurgles. have to hold the handle down to get a good flush. seat is way too much like a chair and the hole is smaller than i would expect. going to get a new seat if possible looks good but that is about it.

    i never should have trashed my old american standard.
  16. dradam

    dradam New Member

    Messages:
    22
    Location:
    Washington
    Thanks for the input.

    I like the old style look of the memoirs-- for the price. I started chiseling concrete this morning-- I hope the outside flange and wax ring without a skirt will make mine work better.
  17. masterbath

    masterbath New Member

    Messages:
    16
    i am glad i did it. i didnt feel good about that flange i put in and everyone here backed that fear up. i was lucky that it only took me about 1 1/2 hrs to resolve. a hammer drill and dremmel tool really saved me. 1st time around i had an air hammer but didnt this time.
  18. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,329
    Location:
    Yakima WA
    Sorry 'bout the mix up on the trap way and flush valve sizes in my earlier post. It still doesn't change the basic advice about the inside fitting flange and the wax ring w/horn. Thanks for the correction.
  19. dradam

    dradam New Member

    Messages:
    22
    Location:
    Washington
    oh boy this is painful

    ok, so I'm chiseling concrete to get my toilet flange over the 3" pipe.

    What please is the minimun amount of pvc overlap to be considered a secure glue weld?

    The flange is long to take into account adjustment for floor height. I would be happy to cut it back to avoid chiseling deeper.

    how short is acceptable ?

    Thanks
  20. Redwood

    Redwood Master Plumber

    Messages:
    7,453
    Location:
    Connecticut
    If it was acceptable they would design pvc fittings with shorter sockets.
Similar Threads: Inside closet
Forum Title Date
Toilet Forum discussions exception to the rule about not using inside coupling closet flange on 3" ABS? Jun 1, 2013
Toilet Forum discussions Inside of toilet PVC pipe has cut marks - an issue? Aug 23, 2013
Toilet Forum discussions Toto C744EG#01 does not feel smooth inside bottom of the bowl May 29, 2013
Toilet Forum discussions Am I supposed to use a metal washer inside the tank or not? Nov 25, 2012
Toilet Forum discussions Question about TOTO Eco Drake 2 float inside tank Apr 20, 2012

Share This Page