Flange/Floor Problems

Dear Friends, I'm beginning to think that whoever put the 4 toilets in our 20-year old house took a few short cuts that led to the problems I'm now experiencing. The PVC toilet flanges - about a half inch thick - were screwed in on top of the floor and, therefore, rest about half an inch above the floor. This means that the toilets rocked, broke the seal and leaked water which rotted the plywood subfloor. In an effort to tighten the toilet down, the top of the flange broke and this exacerbated the problem. OK, so anybody have any good ideas out there! Has to be fixed in any case and has to be fixed right! Many thanks in advance. Arrrrgh!

If the flange was installed tight to the floor, with no gaps under it, it was installed properly. Now, most pros don't like the all-pvc (or any plastic) flanges, since the plastic isn't as strong as those with a metal ring, but a toilet should fit over it. Probably won't if there are gaps, though. If yours rock on it (you sure it is on the flange, and not just an uneven floor), then it needs to be shimmed to stop it. If it actually rocks on the flange and it is tight to the floor all around, then you may need either a new toilet, or a new flange. If you have access to below, that may be fairly easy. If not, it gets harder, but not impossible. They do make an inside pipe cutter. Depending on how tall the riser is (if there is one, and it's not just an elbow), you might be able to cut it off, then install a new one with a metal ring (which typically are thinner). So, you'd need some more info to evaluate how best to fix the problem - pictures would help. You may need to cut some ceiling out to attack it from below.