Wall mounted toilet, drywall broke

[cmo1]

I installed a GEBERIT 111.335.00.5 DUOFIX IN-WALL CARRIER FOR 2X6 for a Duvarit Darling toilet about 10 years ago. Last week the tiled drywall caved in. I saw a few old threats from 2017 about concerns of long term durability of the wall surface. The manual that came with stated cement board, gypsum board, etc were approved substrates. As it turns out to use just gypsum board (Greenboard drywall ) was a very bad idea. Anyone who had the same issue? And any recommendations how to fix this properly.

 

[EIR]

I believe you were referring to my post.


I was searching for my old post when I stumbled upon this one.

As of today, I am beginning to see the caulking crack on the baseboard next to the toilet. Upon loading/sitting on the toilet I can see a bit of flex in the wall.

I'm going to contact geberit like they told me to and am prepared to be disappointed with no refund or warranty help from them.

My solution will be to trace the toilet (paint line should be good enough) unmount the toilet cut out the drywall). During construction and for my application I needed to shim the entire wall 1/4" so I have a piece of 1/4" plywood in front of the carrier I will need to cut out with my oscillating tool.

From there I'm going to drill and tap or self tapping screw some 5/8" plywood (I had used 5/8" fire rated dens armor Sheetrock) onto the lower carrier crossbar to catch the load and then reattach the 1/4" plywood to the surface.

This should accomplish two things:

1)provide a solid interface between the bottom of the toilet and the carrier frame.

2) decouple the wall finish from the toilet loading. If I was to do this over again I would template a plate out of plywood that I traced From the actual toilet, and install that behind the toilet ontop of the carrier. Then tape or caulk the drywall to that. The template could be smaller than the outside dimension of the toilet by a few 1/8"s of an inch to prevent it from showing.

Hopefully the only damage will be to re caulk the toilet and touch up my cut in around the toilet.

This is a poor design and I'm surprise it took 10 years for your install to fail.

Sheetrock and cement backer are or designed for that kind of loading.

I think there is a language translation issue between the manufacturer and foreign markets.

My guess is they use plywood or metal behind their toilet installs elsewhere.

 

[Sponsor]

 

[Breplum]

Incredibly stupid design in the first place, having loading on the cantilevered china pushing against the bottom.
Plywood with thinset tile is the only sensible solution, plywood with drywall will eventually crush the gypsum.
Even plywood with tile, I can imagine the tile cracking from the pressure.

 

[Tuttles Revenge]

The problem here is that there is a gap between the tank frameand the tile substrate. The frame must make contact with whatever substrate is used on the wall so that the weight is being borne against the frame. Some toilets hung on certain frames sit above their cross bars and have similar issues.

 

[Jeff H Young]

What about 1/4 inch steel followed by 1/4 inch hardie backer? from stud to stud

 

[Jeff H Young]

I never worked with resedential carriers but the w/c outline needs something solid I think tuttles said carrier might been too far away a gap allowing the wall to flex my same thoughts with my suggestion for a piece of steel. just a bit of cement board I think is too weak .

 

[cmo1]

Thanks all for your reply. I know there is no other way than opening, changing the backing and retiling the wall surface. I just wanted to post this image to make everyone aware of this problem. I am sure the fact that I used the 1" mosaic tiles did not help distributing the load.