Is the toilet flange lower than the floor? If so you may be able to use two wax rings. If it's much too low, consider cutting the pipe, couple it and lengthen it to meet the floor.

 

Wax rings come in different heights---A wax 'extender ' ring might do it.Adding a small standard ring to the flange first--( carefully press it down to ensure a good seal) then the extender ring might be the answer.


Sometimes you don't need the whole height of the standard ring--just use a knife and slice off a ring of the right height.

Plastic flange extenders are available if the old flange is way below the floor.--Seldom need one though.

---Mike---

 

Buy an extender flange. When you install it, on top of the existing flange, make sure you use a sealer between the two flanges.Then screw through the holes in the extender and attach it through to the subfloor. Double wax seals can leak and sometimes slide while installing the toilet.

 

I've never had a problem with double wax rings leaking. If you decide to use two, make sure they're nice and warm, which shouldn't be a problem this time of year. If they're not pliable enough you can fill the lav sink with an inch of hot water or so and let them sit for a couple minutes. I like the rings with the polyethylene flange, but you'll need to pull the flange out of the top ring or buy one without out the flange. Once you stack them on top of each other mold them with your fingers to seal the two together.