I am replacing toilet and choose to tile the floor first. The inner ring of the flange is deeper and the outer ring is shallow. Should the inner ring be flush with the floor or the outer ring be flush with the floor.

The outer ring should in fact sit on TOP of the tile... this way you can secure the flange through the tile to keep flange from rotating. I am guessing the old flange is already secured to the old floor, so rotation will probably not be a major concern here... BUT...

I would definetely raise the flange using a flange extension kit. These are sold at home supply stores everywhere and each type has a unique way of securing to the old flange.

As a last resort you could always use the extra thick wax gaskets they sell at the home supply stores... AS plumbers we rarely use them (we do have to guarantee our work.. so usually will not take many shortcuts... never seems to pay! )... but as a last resort may work here for you.

YOU HAVE BEEN OFFICIALLY INFORMED (picture me pinching the shoulder of your shirt like on pimp my ride! )!

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