I Am Putting A Bathroom In My Basement. I Am Curious How Far The Closet Flange Should Be From The Back Wall And Does It Have To Be Flush With The Concrete. I Have The Old Concrete Cut Out Where The New Pvc Pipes Are And I Want To Make Sure I Have Everything In The Right Place Before I Fill The Hole Back In.

The center of the flange should be 12" from the unfinished wall (or 11½" from a sheetrock-finished wall). Height doesn't really matter; it can be resting on the floor, or even a bit below (but not higher than the floor level) - the main thing is that the two bolts can hook the toilet (to keep it from rocking back and forth). The flange does nothing other than secure the toilet to the floor; discharge is accomplished by the 4" "horn" on the bottom of the toilet, which goes through the flange and into the closet elbow. In fact, in the olden days, flanges weren't even used - the toilet was bolted directly to the floor.

Cheers
Moishe
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I Am Putting A Bathroom In My Basement. I Am Curious How Far The Closet Flange Should Be From The Back Wall And Does It Have To Be Flush With The Concrete. I Have The Old Concrete Cut Out Where The New Pvc Pipes Are And I Want To Make Sure I Have Everything In The Right Place Before I Fill The Hole Back In.

For a closet rough in, figure 12" from the plate of a unfinished wall or 11 1/2" from a finished wall.
The flange may be a little below the floor line but MUST be at least set flush on top of the floor but no higher. Good luck, tom