Having never replaced a toilet before, I had some questions in the midst of a bathroom remodel.

As part of our remodel, we're replacing the toilet, but we're also planning to lay down tile in place of the vinyl flooring that was there. We have concrete slab subfloors and so we'll tile directly on top of that. Originally, I assumed I would just tile around the existing flange and then use closet flange extenders to get up to the proper height. But the consensus online seems to be that for a better fit, it's best to install the flange on top of the finished floor.

So... after demoing the bathroom and removing the old toilet, I discovered what looks to me like a cast iron flange nailed into the concrete. It's fairly corroded and some of the concrete around it is crumbling. Our condo was built in 1973 (we only just moved in a little over a year ago) and I'm not sure anyone's ever replaced the toilet before.

Needless to say this wasn't what I was expecting to find. I was expecting a fairly standard flange, like the kind you see in all the home improvement books. So I stuck a pry bar under the flange to see how much give there was and whether it could be easily removed and when I pulled up, not only did the flange move but the pipe below seemed to move as well. There's so much rust/corrosion build up that it almost seems as if it's one piece. I stopped immediately for fear of busting something and creating a huge headache for myself (and my downstairs neighbor).

I have a plumber coming next week to move some of the plumbing around so we can install a pedestal sink so I'll probably just ask him then as well, but in the meantime, I was curious if anyone has seen this before and what is the best way to proceed both in terms of flange replacement and preparing for tile and toilet installation. My first thought was just to put a super ring on top of the old one and then build it up to the height of the tile with extenders. But again, I'd like the best fit so maybe I do need to remove the old flange.

Thoughts? I'm not all that knowledgable about or comfortable with plumbing so any help would be greatly appreciated.

 

OK, so I got my courage back up and took a second look. What I thought were nails were in fact screws. There was just so much wax build up from the old wax ring that I thought they were nails. There was also 2x4 blocking in front and in back of the flange into which the flange was screwed. The blocking was covered by plaster which I mistook for part of the mastic residue that was spread out over the rest of the concrete. So I unscrewed the flange then tested it for movement again, and again, the entire pipe (flange and elbow) seemed to move. So is this what is called a flange pipe? I suppose removing the blocking would give me access to it if I or the plumber needed to swap it out.

 

You will probably be better off by siliconing an extender ring to the flange. Of course, if you have a plumber coming anyway, he can advise you better, since he will be able to see what we can't.

 

Arch, What you are probably confronting is a cast iron flange that is connected to the pipe with a lead joint. Take a screwdriver and scratch about 3/8" out from the inside of the pipe. Wax and dirt are probably hiding the joint. Lead will scratch easily and appear silver colored. Whatever type of flange you use, will need to be screwed down to the floor. This prevents movement of the toilet which can crack the flange or pipe. Good luck.

 

Thanks for the responses.

majakdragon: you were right, it is in fact a cast iron flange that is welded to the pipe.

chandler: the plumber said he doesn't think I necessarily need to use an extender as the tile won't be that thick, but he said it coudn't hurt.

Thanks again.