Uneven toilet flange

[robj6767]

I'm going to tile a small bath floor in a rental I own. The flange is set uneven in the concrete floor and the high point of the flange is about 1/8" below the level of the concrete. The low side of the flange is about 1/4" lower.
The tile I'm using is 3/8" so with thinset, I'll be raising the floor level about another 1/2". I know there are flange extensions but I've never used one so I'm not sure just what they're like. Is there a way to both extend and level the flange without chopping out a large amount of concrete?
I'm thinking about using a flange extender and packing it with silicone underneath, would this be a good idea?

 

[phishfood]

You should be able to find a really thick wax ring and a set of long closet bolts. If the flange is otherwise in good shape, that is the route I would go.

The PVC flange extenders that I have seen are glued down, but the bolt still "grabs" on the original flange. I have never seen or used a cast iron flange extender, but if there is such a thing, I am sure that someone will happen on this thread and tell us about it.

If the flange is only 1/8" out of level, I wouldn't worry about leveling it out. The wax ring will still seal.

 

[Mr_David]

Silicon is not a good idea. The surface has to be really really clean for ti to stick and make a watre tight seal. Forget the extender also.
I have at times stacked 3 wax seals but not reccommended.
Use 2 seals - one with a plastic built in cone and one plain.

Way back before my days they used to use plumbers putty to seal toilet bowls before wax was used.