Cast Iron Flange and Installing New Toilet

[BPerry]

I am trying to install a new toilet in a second-floor bathroom, built 1950's. The bathroom floor is ceramic tile. The cast-iron flange is connected to a 4" soil pipe. The flange is rusty and deteriorated, but seems like it will still hold new closet bolts.

The problem I'm facing is that the flange doesn't rest on the floor; there's a 1/4" gap (partially filled with some ancient, dried putty that I can scrape out) between the flange and the ceramic tile. Top of the flange is 3/4" above the floor. The toilet base has only 1/2" of depth. So when I put the new toilet on the flange, the toilet isn't resting on the ceramic tile, and it shifts and wobbles.

Should I use a bunch of shims? Try to grind down the flange with a grinder? Find another toilet -- do they vary in depth? I'm new at this.

Thanks for any help!

[master plumber mark]

its just best to leave that flange alone..

now if the pipe comming up inside the flange is sticking up higher than the flange, you can chisle it down some, ---beware --chips will go flying like little 22 cal bullets. --wear glasses.

leave the flange itself alone... its best to warm up 2 wax rings in hot water , and build up the seal some. its probably a 4 inch cast anyway and you should probably use at least two seals just to be sure ...

You would probalby be wise to shim it up in the back and see if that works.... tighten down the toilet to the shims and that should do it.

Best to let it lean to the front than to the back.....at least you cant see the shims that way and the gap is in the back.

Then it should be pretty solid, all ya got to do is use some
Dap white caulking and seal the unit down all around the bottom extra well and push the caulk into the gap with your finger..

This hides the gap in the back and beefs up the whole job.

wipe it off with a sponge andlet it set up

Dap works almost like elmers glue...once its set up , it aint going anywhere.

[jadnashua]

The engineer in my doesn't like patches. Mark's suggestion will probably work, but you'd then have some significant point loads on the toilet - it is designed to sit basically flat on the floor. I'm not a pro, and I don't have any experience moving/changing out cast iron fittings, so I don't know how much of a major pain that might be. Good luck...whatever you decide.

[BPerry]

Mark and Jim --

Thanks, both, for your input and warnings. I lured a buddy over and we used a grinder to wear down the flange a bit -- fingers crossed on not damaging it -- which worked enough to get the gap down to zero in the front and 1/8" in the back. I shimmed the back end, enough to get it resting evenly with a good seal, and was able to get the toilet on solidly. Again, thanks!

Bryan

[master plumber mark]

sometimes , when all you got to work with is what is laid before you

you simply have to improvise to get yourself out of a mess.

Very few old floors are completely level, ect... so you work with what you got. Some floors I have seen were so rotted out their was very little support left to work with, and of course the customer didnt want to spend the extra money to do it right. You do what you gotta do.

As far as the toilet having to sit completely on the floor, yes that is best, but this is next to best and we both have seen it work fine all the time.....

Unless someone is going to make love on the damn thing, their is never going to be enough bounceing to ever compromise the seal or crack the china.

And if the dap is used liberally, it is basically all one with the floor level or not..


Once, in a dirty old rental dump long ago , I got myself into big trouble. Their was literally no crawl space, and only a 4 inch lead pipe stareing up at me through the mud.

No crawl space and no decent flange either. No way to do anything right.

I had to wood screw down a PVC flange onto the old lead lip into the wood ,

Then around the bottom of the toilet bowl, I spread a 1/2 inch bead of clear silicone very liberally. Then I set the toilet onto the flange, and I pressed the silicone under the lip of the bowl with my finger, basically glueing the toilet bowl down onto the floor.
I wiped off the excess silicone and it looked very , very good.

I screwed down the bolts till they were snug. Then I got the hell out of there. That was 20 years ago and I never heard any complaints.


That toilet was never ever comming up again., and I pity the next poor bastard who has to mess with it.