Basement toilet flange on polish concrete floor

[PunkEngineer]

Hi, I have a problem with my toilet flange installation. The problem is that I have a normal 3 inches ABS pipe that it is cut flush to the Polish concrete floor. So I had to buy a toilet flange the fits inside the 3" inside diameter. But this toilet flange has a inside diameter of 2.5". My toilet hole (also flanged see picture) has a 3" outside diameter that does fit inside the ABS flange. So it leaves a gap between the toilet and the ABS flange. It would result in my toilet not laying on the concrete floor but floating at 0.25". Should I use a grinder to cut a little bit the ceramic flange on the toilet. Or only use a classic copper flange and only count on the wax ring to seal this?

 

[Reach4]

To be clear, what is the ID of the black pipe that is in the concrete?

Nominal 3 inch ABS would have an ID of 3.075.

A glue-in "inside toilet flange is intended to glue into that, but I would worry about a couple of things, including that you have to get a glue-in right the first time. Plus some flanges won't work with that hard right angle at the pipe and floor, and need a bevel. I would consider a Danco Hydroseat for this.

DANCO Model 10672X . Read up on it. You put a normal wax ring under it. I used to think you put another ring on top, but I see they are planning that you just put the toilet on top with no top wax. This would fit cases where the feet are going to be on top of the finished floor, and you can drill holes for the feet. You can use the holes not on the feet to hold it down, or use the hole in the feet if you can drill your flooring easily.

 

[Sponsor]

 

[wwhitney]

In a situation like this, where the pipe is solidly encapsulated in the concrete, is there any reason not to just use the bronze flange shown, secured to the concrete, with a standard wax ring to seal between the toilet horn and the top of the pipe?

I guess if the inside diameter of the wax ring is large enough, part of the concrete would be exposed to the waste stream, with the wax just sealing concrete to underside of the toilet. But a non-wax seal with a extension that fits inside the pipe would avoid that issue, e.g. https://www.fluidmaster.com/products/toilet/toilet-seals/7530-better-than-wax-wax-free-seal/

For the OP, a metal flanged inside fit closet flange might be less tall and let your toilet sit on the concrete (not sure if you could get a full 1/4" that way, though). Otherwise I think you'd have to remove some concrete.

Cheers, Wayne

 

[Jadnashua]

First off, I tend to avoid an all-plastic toilet flange...I prefer one with SS metal ring for the bolts. You need to find a well-stocked supplier with a few different brands to see if any of them have a right-angle between the horizontal surface and the vertical section so it can fit the horizontal section flat on your floor. It's just too easy to crack an all plastic ring on the flange. Tighten the bolts too much, or have the toilet knocked from the side, and you can crack that ring.

You MIGHT be able to taper the top edge of the pipe in the floor to overcome that fairly common radius from horizontal to vertical so it can fit with the horizontal section flat on your floor and you might find that once you add the cement and install it, it melts enough to actually get flat. I don't know for sure on an internal fit fitting, but on the socket of an external fit one, it has a slight taper to it and won't fully seat until the cement is applied and the plastic then melts...so, it may not be as bad as you think it is!

 

[PunkEngineer]

Wow thanks for all your answers and showing me more flange options. I think I'll do as wwithney suggest and only use my brass flange and the wax provided with my toilet. This wax has a little plastic insert that will go a little bit inside my ABS pipe and fits perfectly around the toilet exit ceramic flange. The wax is large enough to cover all the concrete within the flange. Also it is a basement so there no real risk of flooding someone under me.

 

[Reach4]

When using wax, figure out where the shims will be to avoid rocking, and position them before dropping the toilet onto the wax.

 

[wwhitney]

as wwithney suggest

Just to clarify, I don't see any reason not to do that, but I wasn't suggesting it, as my confidence level in bounding what I don't know on this detail is not high. I was literally asking "is there something here I'm missing?"

Cheers, Wayne

 

[Reach4]

This wax has a little plastic insert that will go a little bit inside my ABS pipe and fits perfectly around the toilet exit ceramic flange. The wax is large enough to cover all the concrete within the flange. Also it is a basement so there no real risk of flooding someone under me.

Seems probably OK to me. I might add a little bit of wax to the top of the ABS. I also wonder if that horn is going to wrinkle as you compress things.

 

[PunkEngineer]

The horn won't wrinkle, I measured it (by removing a little bit the wax around it) and its thickness fits perfectly between the toilet base and the floor.

And also I was planning to had a little was on top of the ABS and under the flange to be sure.

I'll try it and see what happens.

 

[Reach4]

The horn won't wrinkle, I measured it (by removing a little bit the wax around it) and its thickness fits perfectly between the toilet base and the floor.

The wax should be higher than the space, so that the wax squishes. Maybe that is what you meant.

 

[PunkEngineer]

This is how I did it. I added some PVC glue on the top of the pipe and concrete to make sure that no water could go between the concrete and the pipe, to create a better seal. After I cutter a little thickness of an extra wax I had to place it under the flange before fixing it in the concrete floor. I placed the wax that came with the toilet under my toilet before fixing all this on the flange. So far so good l, time will tell if all this was all right.

 

[Reach4]

Glad it is working. Thanks for the update. Usually you want to put the wax ring on the floor, and then drop the toilet onto the wax and shims.

Your way required some real precision to center the horn on the ABS.

 

[John Gayewski]

after three years of planning for our next home, my wife and I have decided to build a 600 sq. ft. apartment within a large preexisting pole barn structure. This shop building has an existing 4" slab already poured. My options for adding plumbing and drain lines are:

A) Cut, break up, and remove the existing foundation in the appropriate places and re-pour after the rough plumbing is in place, or

B) Build a raised platform in the appropriate area (where the tub, toilet, sink, etc.. is and run the plumbing above the slab, exiting discretely through the backside of the building.

I'm curious as to what you other folks here would prefer and why.

Just to predicate, the floor plan is being designed in such a way that the main drain line will be very straightforward, regardless of what will happen with the floor. The raised floor idea would necessitate having to step up (about two steps) to enter the bathroom area. There would still be plenty of ceiling height.

Your gonna want to start another thread. Raised floor can be a pain in the ass and look silly.

 

[Jeff H Young]

Chip it out glue a ring on there. its 3 inch pipe. Plenty of short cuts if you want to go that route

 

[Reach4]

I'm curious as to what you other folks here would prefer and why.

ScottLarmr051: Third option is a rear-exit toilet. Pipe is above ground until it isn't. You would have to worry about a hard freeze hitting the above ground drain lines. If things are not clogged, the lines will normally be empty. So some freezing may be OK.

ScottLarmr051, to create a new thread:

If you see the name of the forum you want to post into, try clicking that. Otherwise, click Forums, which gets you to http://www.terrylove.com/forums/index.php

Click the name of the forum that you want to post into.

On the right, click on "Post New Thread".

 

[Terry]

Chip it out glue a ring on there. its 3 inch pipe. Plenty of short cuts if you want to go that route

That would certainly do it, open it a bit around the ABS and put down a hub flange.