Hello all, I'm currently diy on a tiny 1/2 bath reno. Almost every plumber in a plumbing forum has said to install the toilet flange on top of the finished floor, which makes sense to me, yet EVERY youtube or image search shows the flange either mounted to the sub or somewhere Below the finished floor. Each toilet's instructions say that it should be no more than 1/4 above the ff/which is Not on top.
I am now on my 3rd toilet purchase and am considering throwing it out the window.

Final toilet (so far) is a toto drake; under-clearance 5/8.

Using a standard, home depot, oatey pvc flange which measures 7/16, the drake sits flat but almost touching the flange, as soon as I add the ring (I know, more debate about wax v rubber: went with the oatey better-than-wax rubber as I was told an older house (this one is 225) shifts more) the toilet is wildly rocking...not shim-it rocking, but, problem rocking.
Even with plain wax I'll only have 3/16 which seems not nearly enough space.

The sub floor - new 3/4 ply
The floor new 3/4 poplar
all extremely flat and level.

I've tried the stainless steel for a flatter flange but still, it wobbles.

Sorry to keep this debate going, but, I'm losing my mind.

Thinking I have to carefully cut a larger hole with a lip to keep the flange from being too low or too high?!

Any advice is Much appreciated.

Why is the toilet rocking if it is on a rigid (3/4 plywood + 3/4 poplar) flat floor?

i understand completely what you are saying. BUT i don't understand why you are having a problem ???
use the stainless flange and secure it well.
use a plain old wax ring, not the one with the plastic sleeve in it.
apply a thin coat of clear 100% silicone to the base of the toilet bowl.
set the toilet, wipe up as much of the silicone as you can and walk away.
in the morning you will have an installation that you can be proud of.

Worked, as you said, like a charm. Very proud! Thanks for the advice!



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