Offset flange installed improperly - Plumbing Forum

jbradford731 · 01-03-2012, 04:42 AM

Hello everyone. Newbie here with a request for some advice.

Moved into a home in April that was built in 97. About 2 weeks ago the toilet in the downstairs halfbath started rocking and leaking. Replaced the wax ring and couldn't get it to seat onto the tile. Lo and behold realized the flange wasn't installed deep enough in the sewer pipe.

Called AHS, they sent a plumber from ARS - rescue rooter. He said because I started working on it that it wouldn't be covered. Gave my wife a $900 quote to jackhammer the concrete and put in a new flange. I thought that was a little excessive. I've bought a 4x3 offsett flange which looks like it fits inside the sewer line. Also bought a chisel to do the concrete work. Used a masonry wheel to cut most of the top of the flange away. I don't have a dremel to cut from the inside.

I'm a little apprehensive about moving forward from this point and am looking for some advice. Should i buy a dremel and cut/chisel the old flange out, hammer some concrete and cut the sewer drain to the right height? Should the flange be level with the tile?

Or, should i hire someone (a professional) to do the work from here?

If I hire someone, what would be a fair price to do the work from here?

Any advice would be greatly appreciated. Pics are attached.

Thanks,

Brad

**johnjh2o** · 01-03-2012, 12:50 PM

What you need is a inside cutter. It's a very simple job with no need to chisel up the floor. Just cut the pipe to the proper length and install the new flange. Be sure to screw the flange to the floor using tap-cons. I would be a very rich man if I got $900.00 for every one I have done. It's about a half hour job.

Shop Superior Tool Internal PVC Pipe Cutter at Lowes.com

John

**LiQuId** · 01-03-2012, 09:39 PM

all i can add to what john has said is that the inside cutter is called a "pipe shooter" adn availablle at most plumbing stores, it fits into the chuck of a drill... or there are more expensive inside pipe cutters that will do the job also.

what size is the pipe in the cement ? you could install a new flange that will fit inside a 3" or a 4" regardless and this would save you jackhammering anything at all. look into it as bot an inside fit 3" flange and a inside fit 4" flange are made.

jbradford731 · 01-03-2012, 10:55 PM

Thank you both for the advice. The pipe is 4 inch. The flange I bought (in the pics) appears to fit inside the sewer pipe -just like the existing one. The only concern I have about cutting the sewer pipe below the flange onset is that the new flange may be below the level of the tile.

Is that something to worry about?

**johnjh2o** · 01-03-2012, 11:19 PM

If that's the case you could use a 3" coupling inside the 4" then just add a section of 3" between the flange and the coupling.

John

**phishfood** · 01-03-2012, 11:21 PM

You can always use an extra tall wax ring to make up the difference. I chisel down 2" below the floor level at the deepest part right next to the 4" pipe in the direction of the offset. 2" away from the pipe at the floor level, then chisel out the angle between these two points. Cut the pipe, starting at the top, down to the bottom of your chiseling efforts, across, then back up the other side. I don't try to cut off the far side of the pipe, as there is no real need to. Try a dry run, just to make sure that it will fit most of the way in.

Have a claw hammer or pry bar handy to pry it back out in case it doesn't seat all the way, then primer and cement it really well. Get it started, then stand up and step on it, pushing it down to the desired level.

jbradford731 · 01-04-2012, 01:12 AM

John & Phish, thanks for the advice.

Picked up an inside cutter on the way home. Also got an spacer for the top of the flange in case the new one is too deep.

Phish, I'd love to make the angled cut you mention, but have to make a square (perpendicular) cut in order to get the old flange out. If it ends up being to short, I'll use the spacer and an extra tall wax ring. The guy at Lowes said not to use cement. That didn't sound right to me.

How important is it to use anchor bolts in the concrete? If I don't cement I can see it, but don't see the need if I cement (epoxy) the flange in place

**johnjh2o** · 01-04-2012, 02:03 AM

Fasten the flange to the floor and use PVC primer and glue. It's very important.

John

**phishfood** · 01-04-2012, 02:21 AM

Definitely, definitely, use primer and cement on the flange installation. If the sewer backs up, this will be what stops sewage from backing up into your house, and not using the above could cause odor and bacteria to get inside as well.

I would also use some long Tapcons as well. You can often "get away" without in the case of a standard straight flange, but with an offset flange, anchoring the flange to the floor is very important. Consider the "angle of attack" of the upward force on an offset flange. It is much easier for an offset flange to break loose of the solvent cement joint than it would be for a straight flange.