Wall mount toilet wax seal

There are a series of ranch homes in my area, slab on grade construction, that have wall mount toilets. A common problem has been failure of the wax seal every couple years. Much like radiant heat floors where the heat too close to the toilet can melt the wax seal, these seals are melting from the baseboard radiators which run an an adjacent wall. Switching to synthetic rings has solved the problem. I’m now alerting clients to be aware of this situation in my reports.


Excellent observation

There shouldn’t be a wax ring to begin with if this is a wall hung with a chair carrier installation. There should be a neoprene gasket seal.
Wax rings have no memory and will flex against a sheet rock wall.
Something wrong here.


I agree with Marcel. A common problem with a wall hung toilet is the carrier may not be properly braced in the wall. The weight of the user puts a lot of stress on the hanger and it will flex. This constant flexing will result in a wax ring that becomes compressed and doesn’t regain its original shape. A neoprene gasket is what I have always used for commercial wall hung toilets.

As a side note a wax ring will work all day long in a radiant floor.


Agree with that.

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With a melting point of 150°F to160°F I doubt the wax ring is melting with radiant heat. Even with a radiant pipe installed within a few inches of the ring there’s no way that ring is going to get that hot.

I agree. Seems the builder did not get the memo.

Thanks for the melting point info. I agree, typically not a problem. I should have clarified. I have seen two fail. Both log built homes where the radiant heat was added later and attached underneath the floor boards. Infrared showed the lines running right under the toilets.

James I ran radiant heat under my toilet in my last home, wife loved it. 1-1/2” of light weight concrete so the piping was just under the surface. If the toilet rocks even a little on a tile floor I imagine the wax ring will fail with the added heat. If the toilet is properly shimmed it’s a non issue. 12 years no leaks on my toilet.

There was a tenant whose wall-mounted sink kept breaking away from the wall. Turned out the lady that lived there loved to do some hanky panky on top of the sink… Never know what they do with the toilet… just saying :smiley:

Although one should not be used, they do make wax rings for wall/backout toilets, so it is possible the installer used a wax ring, perhaps a standard one, who knows. However, like others, I wouldn’t blame heat for the failure of the “seal”. That could get you in trouble. I remember an older thread about floor toilet and the radiant heat melting the wax ring theory.