I am replacing a toilet flang because of a leaking toilet and also had to take up part of the sub floor,underlayment,and vinyl tile. When I go to set the new flang height, Does the new flang sit on top of the Sub Foor and the underlayment and vinyl tile gets cut around the flang or does the underlayment and tile also go under with the flang screwed into all three?

Thanks in Advance

it sits ontop of everything.. use a flange with a stainless steel collar and use stainless or brass screws to secure it. use a plain old bowl wax not the one with a plastic insert in the middle.
put some clear slicone caulk on the bottom edge of the bowl leaving a few inches with no caulking at the very back. wipe it up with denatured alcohol before it sets up.

It should sit on top of the finished floor and be secured with brass or stainless steel screws.

Leave a capped stub of pipe sticking up.

Wrap it with a layer of 1/4" cardboard.

Finish the flooring up against the cardboard.

Remove cardboard.

Cut pipe and install flange on top of finished flooring.

Secure flange to subfloor with 4 - #10 x 2" flat or oval head stainless screws.



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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Assuming your drains are plumbed in plastic use a ring like that in the picture above, except with the metal part stainless steel. If your drains aren't plastic, what do you have?

OP --- "I am replacing a toilet flange because of a leaking toilet and also had to take up part of the sub floor,underlayment,and vinyl tile."

TO AVOID FUTURE DAMAGE TO A WOODEN SUB FLOOR DUE TO A LEAKING TOILET WAX RING

Before replacing toilet, seal ALL gaps around the toilet flange and any exposed wood with 100% silicone "caulk". This would Include all unused bolt holes and gap between a PVC flange and a stainless steel ring insert --- even around the bolt heads which attach flange to the floor. Wipe / clean surfaces with alcohol before applying the silicone.

In short, seal any and all possible ways that any leaking water could find its way below the top of the floor surface to come in contact with any wood.

As previously posted, after the toilet is set in place, then seal around the bowl leaving a gap in the back to allow any possible future leakage to be detected.

Important to use 100% (messy) silicone which will remain flexible and not harden and crack -- as other caulk over time will.

Disclaimer ----
NOT a plumber. I don't believe I have ever read where a plumber has recommended this simple and common sense tip to help prevent damage to a sub floor

IF

repeat

IF

the flange , piping, and toilet are mounted as per 'best practice',

the wax ring is not necessary to make a water tight seal.

It IS necessary to stop sewer gasses from entering the occupied space.

I am NOT, repeat NOT, recommending that the wax seal be omitted due to stoppages, gasses, misalignments, human error, less than 'best practice' but code compliant installations, etc.

The toilet 'horn' will 'squirt' the effluent into the center of the 4" pipe where it will flow away by gravity - THEORETICALLY.

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638