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toilet drain pipe not square with floor

We are building a barn with a small bathroom in it. The contractor put in the drain pipe for the toilet and poured a concrete floor. When I went to install the toilet, I found the drain is not perpendicular to the floor. The drain pipe has been cut flush with the floor. All the closet flanges I've found have the flange parallel to the base of the pipe (or perpendicular to the long axis of the drain), so when I try to attach it to the drain, one side of the flange is off the floor. I'm guessing the drain is 10 degrees off perpendicular to the floor. It's a 4 inch drain and I though of buying a 3 inch flange, leaving it loose in the pipe and screwing it into the concrete, but figured there might be a problem with the pipes not fitting tightly.

Any suggestions? Thanks, Dave

Re: toilet drain pipe not square with floor

If it is only slightly off square, you should be able to compensate when using the wax ring to install the toilet. The wax will compress and make a seal between the base of the toilet and the pipe. You will just have to tighten the mounting bolts in a way so as to not make the toilet off level...shims may be required.

Don't know that this is the ideal solution, but it may be the only one you have without having to bust up the floor. You might check with a plumber to see if they have any tricks for this kind of situaqtion.

I would not mount the toilet using the three inch flange...if it does not fit tight in the pipe and you have a back-up, you are going to have a pretty big mess.

Re: toilet drain pipe not square with floor

Notion that *might* work for this situation -

Take a normal/standard PVC flange and heat the immediate area where the "pipe" of the flange and the flange ring meet with a heat gun. Wear some heavy leather gloves cause things are going to get hot. You would need to heat the entire 360 degrees so rotation of the either the flange and/or heat gun is essential. When the PVC is eventually hot enough to easily flex/bend (is fluid)... it will turn to a glossy sheen. Heat it a bit more for good measure. Then VERY QUICKLY insert the flange into your drain pipe and press down on the flange-ring so that it sits flat to the floor. Then either have someone quickly spray it with some water or hold it steady for a couple minutes while it cools and the PVC sets again.

If all goes well...you'll have a custom offset bend to accomodate your needs. There might and probably will be... some wrinkles in the plastic where the bending and stretching took place, but not enough to inhibit the passage of flushed "materials".

(Make sure when "insert and bend" time comes that you have the flange properly situated so that the hold-down/johnny-bolts are parallel to the wall behind it. IOW, you might want to place some marks on the floor ahead of time that are parallel with the wall to help you situate/rotate the flange quickly at crunch time. If not properly/reasonably aligned, your toilet tank won't sit parallel with the wall....as this custom bended piece won't really be very "rotate-able" at glue up time.)

Re: toilet drain pipe not square with floor

No need to worry. Just use a closet ring that sets flush to the floor and seal between the ring and pipe. Having the stool riser out of plumb happens once in a while. The concrete finishers bump them and never fix the problem. Good luck

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