What do you mean by a "T" (tee?)? Can't use that.

Well shoot. It's a sanitary tee if that makes a difference. If a sanitary tee is not what is needed, what do I replace it with?

If the sanitary tee is ok, the question remains. I've attached a photo, where you can see that the socket is right up against the bottom of the subfloor. The total depth of the floor is less than the 2" socket of the flange.

I'm pretty peeved at the people who roughed in this plumbing. I've found error after error (unsloped drain lines, stacks sticking out of the wall stud cavity by 8", reversed hot and cold lines) that I've had to fix myself, and I'm hoping that this one is as easy as a special fitting with a shortened gluing socket.

It never occurred to me that the tee fitting was incorrect, but now that I've read a little more, I see that it needs to go. I'll pick up a combo wye and a new sawzall blade and get to work. Thanks.

Does the contractor who did the rough in have a plumbing license?

I assume there are no permits for this work.

If you had pulled permits, you would have the assistance of the inspectors to help catch all these code violations.

The contractor should not be paid for any of this work. He is not a plumber. If he has a license, report this all to the License board. NONE of the mistakes you found are acceptable in any circumstance. These are straight up, violations, and your plumbing will not work. This can be a health and safety issue..

And back to your original issue about the height of the flange, the Wye combo will not work. The flange will be even higher than the sanitary tee. The entire line needs to be lowered by about 3 inches.

Aiden - thanks for your response. I will have to remove a lot of the drain line to be able to do it properly, but it WILL be done right. Fortunately this section of plumbing is isolated from our primary bathroom, so I can take my time. And I'll be taking out some of the hodgepodged "fixes" they did before, so maybe this is a blessing in disguise.

The guy is a licensed general contractor but he usually subs out his plumbing work. Wonder why! He didn't on our job because it was supposed to be so minor. Unfortunately he's already been paid, two years ago. I'm doing the rest of the reno myself. I've had 2 babies in the intervening years so it's been slow going, made slower by the fact that I keep having to re-do stuff that they did wrong.

"made slower by the fact that I keep having to re-do stuff that they did wrong." I hear you.

Every house I've owned (3 so far, in two different parts of the world) has involved a lot of remedial work to do stuff right.

Good on you for doing it right, now, rather than kludging something. When you do the flange, my personal (amateur) recommendation is to use one of those stainless steel flange cover things - it goes over a regular flange, and more or less reinforces it.

I also like the Fernco waxless seal. It seems like a much better system.

Here is a link that might be useful: Fernco waxless seal

Thanks for the tip on the waxless seal. Reducing the diameter of the pipe by inserting the waxless system doesn't reduce efficiency?

I had planned on using an Oatey flange with the stainless steel ring already on it. Is that any better or worse than the separate flange cover?

Here is a link that might be useful: Oatey Stainless steel flange