I removed some bathroom tiles and much to my disappointment, the person who laid this out years ago did a horrible job and I’m now left with this mess to fix.
I’ll be adding a 2 inch foam base (concrete basement) and a 3/4 inch plywood subfloor.
I’m thinking about grinding this mess out and filling out a 2 3/4 inch thick concrete “block” where the new outlet pipe will sit on. About 3-4 inches wider than the outlet bracket so that the foam base and subfloor will be level with the block.
Hope this makes sense.
My only question is how to extend/raise the outlet pipe – I don’t want to dig out all the concrete, but feel it may be better for foundational purposes. Is this the correct approach?
Any thoughts on this would be appreciated as I really dont know how to fix this.
Best Answer
I would absolutely be cutting concrete. You have an ideal opportunity to do so since you're overlaying the floor anyway. You don't want to deal with clogs later due to pipe reduction from an extension, and you want the stability a proper flange provides.
Rent or borrow a diamond saw, cut out a 24" square, and fix this up right with a full-size pipe. Mix up some bagged concrete and pour it to the level of the new subfloor for a stable base (just as you describe). Use strips of the foam and sheathing as a form.