Hi folks,

I have just ripped up my tile floor and also the subflooring along with it. I've reinstalled new 5/8" plywood on the floor and am about ready to lay down tile, but also have to re-install my toilet. The question I have at this point is simply whether I should anchor my closet flange to the plywood subfloor and then tile around it, or if I should be tiling and then adding the flange over top of the tile. I'm not sure if one way or the other is code or not. I'm in Ontario, Canada. I also have a bit of a space issue in that from the bottom of the flange to the top of the drain pipe there is about an inch of space, but I think that should be easy enough to find a piece to close that gap. Any suggestions out there on the flange install? Thanks for looking.

Regards,

Sam

You can do it either way. If you have an inch between the bottom of the flange and the top of your new subflooring you will want to slide you tiles under the flange. That will take up about 1/4 to 3/8 of an inch.
What kind of pipe and flange do you have? If PVC you may be able to pull the flange down a little with the screws. Turn the toilet over. Lay a straight edge across the horn and measure the distance between the straight edge and the horn. If that measurement is greater that the distance between the top of the flange and the subflooring, the toilet will fit.
The other option is to lay down another sheet of subflooring. That is indeed probably the best any way. That second sheathing should be cement board if you are installing ceramic or porcelain tile.

Opinions will vary. You can mount the flange before tile is set, as long as the top of the flange is at least even with, or slightly above the finished tile. However, as a plumber, I believe it is the best plumbing practice to always set the flange on top of the FINISHED floor. Then you would use a tile drill bit to drill through the tile and anchor the flange into the plywood through the tile. This is the best way to set a flange, but like I said, you can set the flange before tile, as long as top of flange is not lower than the finished floor.

I generally ask what the finished floor height will be and then cut and hole-saw a piece of plywood to bring the flange up to the proper height at the rough-in stage.

The blocks are then secured to the floor with screws and construction adhesive before the flange is glued and screwed.

We should talk on this point further "bottom of the flange to the top of the drain pipe there is about an inch of space" Do you mean there is a gap between the top edge of the pipe and the bottom of the flange?? What is the pipe made of?

We set our flanges on the finished floor whether it be tile or vinyl. If we secure the flange we use Tapcons on a cement slab and wood screws or a raiser clamp for a second floor installation, Regards, Tom

Hey everyone, I realize this is late getting back, but in the end I did tile first and then secure the flange over the finished tile floor. Works great.

As for the gap from the bottom of the flange and the top of the pipe it connects to I used a coupler (?). It's a 4" long piece with clamps on both ends. It's been installed for some time now and is operating as promised. Thx for all the replies, much appreciated.

Thanks for the update. Glad things worked out.