New closet flange?

[ddeslaur]

Great source of invaluable information....

I am about to lay porcelain tile in a bathroom where vinyl had been previously. The PVC flange now "floats" just above the 1/2" plywood underlayment. I say floats because the underlayment was cut around the flange and not placed under it. The flange is not secured to the 3/4" plywood subfloor that is below the underlayment either. I plan to use hardibacker and then the tile over the 1/2" plywood underlayment thus raising the new floor about 1/2" over the existing flange. From what it sounds like the best option is to cut out the old flange, using a drill bit designed to cut from inside the soil pipe, lay the cbu and tile, then install a new flange on top of the tile and fasten it to the 3/4" subfloor? Does that sound right? Also how far in/down should I cut out the old flange? I can't really tell where the flange ends and the pipe begins.

Sorry for the long post....any help would be greatly appreciated.

Thanks, Doug

 

[Cass]

Is it cast iron or plastic?

 

[Sponsor]

 

[hj]

flange

Is the flange glued on the inside or outside of the pipe riser.

 

[ddeslaur]

I looked at this assembly a little closer last night....all components are PVC....Is it possible to have an "all in one flange"? That is to say The flange the riser and the bend/elbow are all one piece. That is how our set up appears anyway...the only place I can see a clear connection is below the subfloor where the elbow/bend connects to the main pipe(sorry don't know what that pipe is called runs horizontally under the floor away from the commode) main pipe appears to be glued inside the bend . If this is the case where should attempt to cut, or should I just user a flange spacer and two wax rings, if need be, and not worry about it?

 

[ddeslaur]

In looking at some plumbing supply catalogs online it looks like the setup we have is attached below. As I mentioned earlier the new tile floor will be about 1/2" above the flange. If it is recomended that I replace the flange how best would I go about doing so?

 

[Jadnashua]

Ideally the flange should sit on top of the finished floor, fully supported underneath by that finished floor and attached to it (well, cast iron is strong enough to just sit there normally). If you tile under it - it is easier to cut notches in the tile so you don't have to drill through it into the subfloor to anchor it in place.

I'd prefer to replace it if it was mine. The deeper the wax, the more susceptible it is to blow out if you plunge it. How serious that is, I'm not sure; one of the pros will have some thoughts based on experience.