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Discussion Forum

closet flange too high on slab floor

nuthole | Posted in General Discussion on February 5, 2005 07:14am

I have a 30 YO house with a slab foundation, and the closet flange is above the level of the slab. This fact was hidden for years by carpet in the bathroom. The termites brought the problem to my attention. Now that I have ripped out the stinking carpet, I found that the closet flange is above floor level, the carpet was what kept it from rocking. The front of the toilet sits about 1/2″ above the slab, before the wax ring is added. I plan to tile the floor with 12″ tile, and am looking for options to level the toilet.

Some possibilities I have considered:

Float out the tile to make a level place for the toilet to rest. The toilet is in a 30″ alcove, and the rise to make a level place would seem to mean cutting and piecing tiles to make the quick rise, plus the toilet would be perched higher than standard. Although I like to be king, it feels like sitting on one of those handicapped toilets. Lower works better.

Chip/cut concrete slab until the area around the flange is level or below  the rest of the floor, then cut off high flange (cast iron) and replace with plastic. I know this is an ugly job, but it seems to be the method that would give the best results. How do you go about cutting the concrete? Just chip away with a 4# sledge? What about cutting the flange off? Could I use a small angle grinder? I can only imagine what the frying dookie smell will be like.

If anyone has experienced this problem, please share your solution. I am not stuck on any method yet, and so far I haven’t destroyed anything. 

 

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Replies

  1. JamesDuHamel | Feb 05, 2005 08:26pm | #1

    1/2" ain't that much if you're going to install tile. By the time you get the thinset and the tile in place, thetre shouldn't be much of a gap, if any. If there is a small gap, use thinset to fill in the area.

    If there is a small gap between the base of the toilet and the tile, use thinset to fill it too, and smooth it out (like caulk).

    Is the pipe itslef cast iron too?

    James DuHamel

    He who dies with the most toys.... Still dies!

    "For what will it profit a man if he gains the whole world, and loses his soul?" MARK 8:36

    http://www.godsfreemusic.com



    Edited 2/5/2005 12:28 pm ET by James DuHamel

    1. nuthole | Feb 05, 2005 10:00pm | #4

      The pipe is cast iron, too. The reason I see a problem is the flange isn't just higher than the slab, the concrete was floated up to it, so the flange is actually on a small hill. With the wax ring in place, it is higher than 1/2". If it was only sticking out above the slab, the tile would solve the problem, but as it is, the tile will have to follow the non- flat floor, and just duplicate the problem, but with tile on top. I guess I should have asked, would it be best to flatten the hump off around the flange, then tile? What's the best way to chip out concrete? 

       Yes, those were some serious termites. They can hide for a long time under carpet, eating everything but polyester fibers and the last layer of latex paint on the walls.

      1. FastEddie1 | Feb 05, 2005 11:14pm | #5

        How big an area is the mound arond the flange?  If it is smaller than the footprint of the potty, you can install tiles up to the point where the mound starts, then fill in the rest of the area with thinset or floor fill after the tile is down.  Or maybe just chip away a small area of the moiund to get the tiles under the footprint.I'm sorry, I thought you wanted it done the right way.

  2. User avater
    IMERC | Feb 05, 2005 08:54pm | #2

    with 12" tiles and thinset there is an excellent chance that you'll gain almost 3/4 of an inch in elevation...

    proud member of the FOR/FOS club...

    Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming

    WOW!!!   What a Ride!

  3. User avater
    IMERC | Feb 05, 2005 08:55pm | #3

    BTW... those are some serious termites ya have there...

    proud member of the FOR/FOS club...

    Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming

    WOW!!!   What a Ride!

  4. DonCanDo | Feb 06, 2005 12:39am | #6

    I needed to raise a rear-flush toilet about 2" to meet the flange in the wall.  I made a form to the exact shape of the base of the toilet using vinylized concrete patch.  The form was a combination of masonite (bent to shape) and wood scraps.  Once the concrete cured, I glued the platform to the floor and set the toilet on top.

    It works perfect and doesn't look too bad either.  If it were one of the main baths, I would paint and caulk the platform to match.

    For your situation, the only difference is the thickness of the platform and forming a hole in the center for the toilet flange.

    -Don

    1. nuthole | Feb 06, 2005 01:40am | #8

      Ed, the mound is pretty tapered from the walls to the flange, so that's about 12" on either side of the hole. Looking closer, I can see that the original slab finishers brought it up close to the flange, and a little patching was added around it also.  The flange is also not level, tilts a little to one side. This wouldn't be a problem if the toilet actually sat on the floor, but its main contact is only the flange right now, I've had to put wedges under the front and back to keep it from rocking and leaking.

      I think you guys have helped me see that if I can bring the concrete mound down to the level of the floor's edges, the tile thickness should bring me up to the flange level, hopefully a little above, then I won't have to worry about the flange not being straight.

      Don, I thought about making a vinyl patch or concrete base like you suggested, but I'm afraid that will make me have to cut a lot of tile to accomodate the angled base, like a mosaic. Since I want to use large tiles, I'd rather have as many whole pieces as possible.

      Any suggestions on how to chip away at the slab? Just a small sledge, or chisel, or should I score/cut the slab with a masonry disk in a grinder first?

      1. FastEddie1 | Feb 06, 2005 04:11am | #9

        Two options for knocking down the mound:  a 4-1/2" side grinder with a diamond blade will work real well, but it will kick up a huge amount of dust.  A chipping hammer is a little slower, but much less messy.  I have a Bosch Bulldog and it works ok.  My plumber used a Hilti and it was much quicker.

        If you don't already have a chipping hammer, the B osch might be a good purchase cuz it makes a very good hammer drill.  I think the Hilti is only a chipping hammer.  The Hilti also costs more.

         

        I'm sorry, I thought you wanted it done the right way.

        Edited 2/5/2005 8:13 pm ET by Ed Hilton

      2. BillBrennen | Feb 06, 2005 05:28am | #10

        nuthole,To lower the slab hump you can chip it away if the concrete is poor-to-medium quality. If it is old, smooth, and hard, then diamonds are a boy's best friend. You will want a diamond cup wheel on a mini grinder, shrouded and sucked by a good vac with a paper filter bag in it. One good shroud is the "Dust Muzzle" for $25. Google it and you can buy online.I second the vote for the internal replacement flange, if it will work in your pipe. tilting floor flanges are just wrong. That thing wants to be level.Good luck on your project. If you could take some photos to post, we would enjoy that a lot.Bill

  5. User avater
    BillHartmann | Feb 06, 2005 01:36am | #7

    Something to look at is it cut off the flange flush with the concrete. Then install a replacement internal flange.

    The make ones that have an expanding o-ring that will seal it up. You need to verify the ID to see if that will work. As what is left will be part of the old flange so I don't know the ID.

    Another option is based on what Don suggested. You could make an shim plate out of solid surface (Corian) scraps.

  6. butch | Feb 06, 2005 02:54pm | #11

    http://www.hilti.com/holcom/modules/prcat/prca_navigation.jsp?OID=-10966

    This is the best way to remove high spots in your concrete, with the least

    amount of dust. You can rent hilti at Homecheapo but the bushing bit

    you may have to purchase.

    I use one all the time for removing excess concrete (to high) around floor drains

    when I'm prepping for vinyl compostiton tile.

    I've used an angle grinder w/diamond blade before and it is no fun.

    1. nuthole | Feb 06, 2005 08:54pm | #12

      Thanks to everyone for your replies. I've got an air chisel, I'll check to see if anyone rents or sells a head to fit my chisel. If not, I don't mind renting the whole tool. Thanks for the warning on the dust from cutting. I'd rather avoid that, I know how it spreads through the whole house, no matter how careful you are.

      I will be glad to post pictures after I'm done, but you'll have to wait a while. This job started because I saw the termites. Then the carpet had to go, then the floor had to be cleaned before tiling, but before tiling, I might as well paint the ceilings, and walls, put in some recessed lighting, remove, regrout, and reseal all the tile grout on the walls, and so on. I know I'm not the only one who gets into projects this way. Well, the job is mostly done, I'm at the floor tile stage, and the hang up is the toilet flange. Time to get in there and chip away. Yes, this is old, hard, shiny concrete, and like everything else on this project, if there are two possible scenarios, mine will be the harder one. My neighbor told me spraying muriatic acid on the grout would just wash it out, then rinse and regrout. Maybe if it wasn't made of Kryptonite, like mine.

      Anyway, here is my reformulated plan: I'll chip the mound to level it with the rest of the floor. Bring tiles in and adding height for mortar, check to see if they come level with, or hopefully, slightly above, the flange. If not, I'll cut the flange off lower, then replace to the tiled floor height. Install tiles, install flange, replace toilet, then dump this job off my mind. Thanks again.

      1. ClaysWorld | Feb 06, 2005 10:23pm | #13

        If it's a cast iron flange then it's a lead joint? I don't know what the big problem is? You want to remove the flange as the starting point so you need to research a little to see what your dealing with. the important thing is not to break or fracture the closet bend/pipe. You can torch out the lead and remove the flange or you can drill/chisel/fracture the flange till it's in pieces. Finish the tile job and leave enough space for a new flange and lead a new joint.
        don't rebuild the house around the problem, fix the problem.

      2. DanH | Feb 07, 2005 10:08am | #14

        Note that the "correct" height for the flange is to be proud of the finished floor about 1/4", essentially as if the flange were tight against the top of the finished floor.  The lowest the flange should generally be is flush (on top) with the finished floor, and at that point you may want to consider using an extra thick wax ring.

        1. ClaysWorld | Feb 07, 2005 11:08pm | #15

          Yea but but but I sure am happy when it's low as opposed to high.

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