No Toilet Flange

My bathroom toilet does not have a toilet flange. It is not bolted to the floor and is sitting on a wax ring which is sitting on top of a flared piece of pvc which is attached to a 3 inch pvc waste pipe. My questions, when I pull this toilet and install a new toilet flange to a plywood floor, does the toilet flange attach to the PVC at all or is it just secured to the floor? Is the wax ring the only connection between the toilet and the PVC? Do toilet flanges come in different sizes, 3 inch, 4 inch or does one size fit all? I'm confused and would appreciate any help. Thanks.

Willie

Flanges come in 3" and 4" sizes to match the size of the drain and are solvent welded to the drain. The flange rests on top of the finished floor, and you must make sure the holes for the tee bolts that bolt the toilet to the flange are properly oriented, then screw the flange down solidly, with the screws going through the flooring into the subfloor. The ring, either wax or waxless, is the seal and the only physical contact the toilet has with the drain. Everything else rests on the floor. Although directions for the ring often say to set the ring on the flange first, many installers find it easier and more certain to get a good fit if they put the ring on the toilet first. Make certain the toilet and ring are seated in the closet bend by rocking the toilet while you apply downward pressure. The tee bolts are not intended to pull the toilet down, just to keep it in place so you should only have to snug the nuts. On other note on flanges, they also come in either fixed or adjustable models. You only use the adjustable if you need to compensate for a poorly located rough-in. That is to say more or less than 12" from the finished wall. Make certain that you match the type of flange with the type of pipe, PVC or ABS.