10" versus 12" toilet - what have I got?

Discussion in 'Toilet Forum discussions' started by dirtmover, Oct 3, 2013.

  1. dirtmover

    dirtmover New Member

    Messages:
    64
    Location:
    Ontario
    Just bought and older property. The flange is centred about 10.25" from the wall, 10" rough in I assume?.

    The toilet sits with the tank touching the wall. The flange bolts are tilted forward into the holes, on the toilet, which are centred about 10.75" from the wall. It fits, almost, but not quite :(

    I removed the toilet. The floor has been raised with tile and backer board so there is currently about 3/4" of spacer on top of the flange which brings it flush with the tiled floor. This is not enough since the wax ring has clearly not been fully in contact with the bowl.


    Sounds a stupid question but is a toilet with holes 10.75" from the wall a 10" or 12" toilet? If it's any help it's a Glacier Bay and I believe they had a 10" model but discontinued it some time ago. I think it would maybe be OK with an 11" rough in but what I have is not quite enough.

    In a typical install, how much gap would there normally be between the tank and wall i.e. how much clearance does the manufacturer normally allow? Any spec sheets I've seen show exactly 10" or 12" from the mounting holes to the back of the tank but surely they allow some margin?

    What is the best way to deal with this situation? I'm suspecting a new toilet may be the easiest solution?

    How about the flange height? Should I stack 2 wax rings? Horn or no horn? What about one of these waxless adapters? Or maybe just another spacer with a single wax ring? So many possibilities.
    Last edited: Oct 3, 2013
  2. wjcandee

    wjcandee Wise One

    Messages:
    1,771
    Location:
    New York, NY
    First, try measuring from the "finished" wall, not from the baseboard, and see if that makes any difference in your calculations.

    There is no standard for how much room should be behind the tank on a 10" or 12" rough-in toilet. It only means that the toilet will fit in that space for sure. In the Toto line, there are toilets (just a couple) that require the whole 12", which is very unusual. Most will fit on less. Typically, it's 11.25 or 11.5, but one will go on 10-7/8".

    Use two wax rings (no funnel on bottom one, one funnel on top one to hold it in place) or an extra-thich (#10) wax ring.
  3. dirtmover

    dirtmover New Member

    Messages:
    64
    Location:
    Ontario
    Yeah, my measurements are from the wall. I think the previous owner just squeezed that toilet in best he could and ignored the fact that it was about 1/2" too big for the rough in. The fact the bolts were angled forward and the bowl was wobbling is what got me investigating.
  4. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,293
    Location:
    Cave Creek, Arizona
    Economics, since a 10" toilet can cost twice as much as a 12" one, sometimes dictate that the installer try to "force' the 12" bowl to fit a smaller rough dimension
  5. dirtmover

    dirtmover New Member

    Messages:
    64
    Location:
    Ontario
    In this case I think it was probably ignorance. Plumber? I don't think so! This was a DIY job and he probably didn't even realise that he'd got the wrong toilet for the rough in. It was pure luck it was even this close.

    I've seen pretty decent prices for 10" rough ins in the US e.g. American Standard Colony @ $112 but up here they're not so forgiving and the same thing will cost me 50% more.
  6. Terry

    Terry Administrator Staff Member

    Messages:
    14,799
    Location:
    Bothell, Washington
    A drain will either be 3" or 4"
    The horn of many bowls will be 2-5/8", which at the least gives you 3/8" to play with. I sometimes use a repair ring to recenter the holes farther away from the wall, and then drop down a TOTO Drake, which installs at 10-7/8" if needed.

    Or you can pick up a 10" rough toilet. You're going to have it there a long time.
    We throw away a few Glacier Bay toilets when we come across them. I've seen them produce some real junk.
    Unless the floor flange is on top of the finished floor, you will need more than one wax seal. Stack two rings on the floor, and if you don't feel compression on the wax when you drop the bowl down on it, it can even take a third.
  7. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,308
    Location:
    Yakima WA
    You might want to look at one of the Toto toilets that use the Unifit adapter. These are not cheap models, but with 3 adapters to choose from, the same toilet will fit 10", 12", and 14" rough ins. These adapters are Toto exclusive and will only fit on their skirted models. They are excellent performers. As noted by HJ, true 10" toilets are not too plentiful and may be costly.
  8. dirtmover

    dirtmover New Member

    Messages:
    64
    Location:
    Ontario
    I think this may work as I only need to move it about 1/2" forward.

    Should I:
    - put the repair ring above the spacers
    - put the repair ring below the spacers and move the whole "stack" forward by 1/2"

    also, which repair ring to use:

    http://www.lowes.ca/search/toilet-flange.html
Similar Threads: versus toilet
Forum Title Date
Toilet Forum discussions You've heard this before - offset flange versus toilet with shorter rough-in Aug 24, 2012
Toilet Forum discussions Tankless versus Tank toilets - which to consider for church? Mar 2, 2010
Toilet Forum discussions Toto Drake EL versus SL toilet Apr 29, 2008
Toilet Forum discussions Pros & Cons of Wax Free Gasket versus Wax Gasket on Toilet Installation Jul 15, 2007
Toilet Forum discussions wax versus no-wax rings Jul 3, 2014

Share This Page