Simple newbie question:
I’m in the process of remodeling my bathroom and am about to rough in the toilet. The floor will be ceramic tile on cement backer board on plywood.
Does the toilet closet flange go on top of the ceramic tile or on top of the backer board?
Replies
This is just a guess, because I cannot certify my observations, but I seem to recall seeing my plumbing contractor put the flange right on the subfloor, before floor finish (including any underlayment like backer board) went in.
The plumber either has a selection of varying length T-head toilet bolts, in order to deal with this, or cuts them, or the caps that sit over the bolt tops accommodate the extra length that may protrude.
Of course, what you do relates also to the amount of height play the wax gasket ring can ammodate.
Let's see what the pros say now.
Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Just did a bath with a tile floor. I cut a nice hole in the tile under the toilet (yes, the toilet inconveniently landed right in the middle of a single tile). I was prepared to cut some tile shims to let my plumber shim the flange up to the tile surface, but he installed it right on the hardibacker and set the toilet. So, the flange was about 5/16" below the finished floor and bob's yer uncle.
I have also done them where the inspector wanted to see the toilet flange roughed in and shimmed up above the backer board. He actually wanted it installed permanently before the tile went in, which I griped about, so he let me do tile first, but he wanted the flange on top of the tile.
Between those two guys, I am quite sure my current plumber knows more.
In a perfect world I would try to get the flange so it lies flush with tile surface. Shim as neccessary to achieve this, if not look for wax ring with horn flange to get a good seal with water closet and floor.
In general, the top flange surface should end up somewhere between flush with the finished surface and about 1/4" (the thickness of the flange) proud of it. However, it's not good to go higher, since you may smash the wax ring flat, but you can go lower with an extra-thick or doubled ring.
It's ideal if you can leave the pipe a hair loose and then fasten it down on top of the finished floor after the floor is in (or perhaps leave the flange off entirely until after the floor is in). Just be sure that you'll be able to get the flange flat on the finished floor after all is done.