Unless the flange is above the floor, it's going to take two wax rings (or perhaps a thick one)
Many tile floors are layered in such a way that the flange is too low for a single wax ring.
I have a toilet that has been installed for about 2 years. Today I noticed a little seepage on one side by a grout line. The toilet is installed over tile on a concrete slab. The toilet is mounted solid and does not move. It has never been stopped up and never plunged. I don't understand why they just start leaking.
Anyway, can anyone recommend a good wax ring? I have just always used the rings from the big box stores.
TO make a decent seal, you must be able to feel the toilet compressing the wax ring when you set it down.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013
For floor mounted toilets I use a waxseal without the plastic handyman horn. IMO the horn only is there to restric flow and to allow splashing. The bottom of the flange should be sitting on the top of the finished floor. I only use one waxseal and with a correct flange height thats all that is needed. if the flange height is not corrrect then I make it correct.
I do it right or not at all.
Then you would be pretty busy in the State of Washington.if the flange height is not corrrect then I make it correct.
At least 95% of new construction has the flooring cut around the flange making it recessed.
The only really good way of raising the flange, would be to cut it out completely and install a new flange from scratch. Stacking waffers on top is a joke. Those leak worse then using wax.
Though my customers get by fine and without leaks using two wax rings. Maybe they are just better at settiing bowls than the plumbers.