Before we begin...

[cricketlegs]

We have a new construction bathroom project. We used Kerdi products. The membrane for the shower is over drywall. The bench is plywood covered in membrane.We are trying to make the most of a small space, which is why we chose the membrane method. I put the membrane down two years ago and we're just getting back to the project to tile it. Before we begin, we have a few questions and I'm just hoping to pass our plans by you all in hopes of avoiding catastrophe.
The main concern is that on the angle wall there is a handprint size area where the membrane is not adhered to the drywall, as if there's an air pocket there. From reading other posts, my guess is that we would fix this with Kerdi fix. Is this correct? And if so, do we just make a slit and inject it and then would we have to patch the slit? Everywhere else seems to be adhered well.
Aside from that, I want to add a picture of the products we plan to use incase there are concerns about their usage. Sorry about the sideways pics, I couldn't get them turned properly.
Thank you!

[speed51133]

What mortar did you use when setting the kerdi? Are you planning on using that floor tile mortar for the shower? I would consider something better. That mortar is designed to be used by mixing it WITH Mapei Keraply and NOT water for your installation. ALso, it is ONLY approved for use on the floor. try something like this: https://www.lowes.com/pd/MAPEI-Porce...Mortar/3743821

I presume you used it because it is not modified and Schluter wants that when affixing kerdi. While it can be used and your kerdi is already set, there are better mortars approved for kerdi. That ship sailed.

[cx]

Welcome, Dawn.

Two years? I know Schluter has said how long the Kerdi could be exposed before tiling, but I don't recall what the time is nor could I find it online or in any of my current publications. I'm also not sure what problem they would anticipate.

For your bench, Schluter does not permit Kerdi to be installed directly to plywood. And if your Kerdi was installed with the thinset mortar you show in your photos, that could certainly be a problem.

For the un-bonded area on that sloped ceiling, due to the horizontal component there I would recommend you cut out the unbonded portion and install a Kerdi patch extending at least two inches beyond the perimeter.

My opinion; worth price charged.

[John Bridge]

Hi Dawn,

I, also, worry a little about the bench.

[cricketlegs]

I hate relying solely on my memory, but I'm 99% sure that this is what we used for the membrane.

Is the concern with the bench how well the membrane adheres? Would the tiles just pull the membrane off? Is there anything to be done about that at this point?

I will make the switch to the other mortar, thank you! (Would we use that on the floor as well as the shower?)

[Elkski]

My neck hurts.. why are so many people having issues with rotated pictures?
I will let others pile on the bench issue.
I will say it looks like a great use the of the space.
How did you stop at this point you could see the light?
What door are you planning?
If glass is going in the center of the curb it seems like it maybe hard to clean the end of the bench and that water can pool in that space on top of the curb.

[cricketlegs]

Ugg, life got in the way. We live in two states and are overextended, blah, blah, blah. Believe me, we're kicking ourselves.

We're hoping to use no door, but will have one customized if the water is too much of an issue. (We're open to suggestions.) The floor of the bathroom itself is covered in ditra and tile.

As far as the bench goes...what about covering it in Kerdi board or even in cement board???

[cx]

The only fix I could recommend is that you remove the Kerdi from the bench area and anyplace you've bonded directly to plywood, cover those areas of plywood with drywall or CBU, then apply Kerdi, overlapping onto clean Kerdi at least two inches all around your new work.

Or you can just continue on with what you've got. I wouldn't.

Part of your problem there is that the only thinset mortar approved for bonding to plywood is a modified thinset mortar meeting the requirements of ANSI A118.11. Doesn't meet that standard, won't bond properly to plywood.

My opinion; worth price charged.

[cricketlegs]

Thank you. I'll pass this by my husband and he can make the call. I'd rather have it done right.

I'm pretty sure I watched someone do exactly what we did, but that could have been the blind leading the blind...

[Houston Remodeler]

When you're rebuilding the bench it would be a good idea to think about placement of the glass panel and how easy it would be to clean between the tiled bench and the glass panel.

[Elkski]

That shower looks rather small for a walk in, no door or curtain.
Did you Use the Schluter inside corners in that shower? bottom corners? And they also make a corner for where the bench meets the wall. It looks like you used all those I just cant see them in the back 2 corners of the shower. I think they are the only way to seal the corner properly.
I think if you used kerdi board on top of the plywood and then sealed all the edges and corners properly it should make most guys here happy. It may maker the bench taller than you like. How tall is it?

and don't be to hard on yourself about that unbonded part on the ceiling I'm sure that kerdi piece was falling on your head.. just cut it out and patch it like CX suggests. If
you do rebuild or add on to the bench consider extending it out flush with the outside of the curb. Then if you do go with a glass door you could have a fixed glass on the bench and the door for the opening.

[speed51133]

thinking outloud, but why can't they just screw in 1/4in durock to the bench as-is, then kerdi over it and seam it????

I would also extend the bench the full width of the curb.

[smifwal]

Originally Posted by speed51133

but why can't they just screw in 1/4in durock to the bench as-is, then kerdi over it and seam it????

moisture sandwich!?

[speed51133]

That's assuming your first layer of kerdi will fail. If it does, I would rather have a moisture sandwich than water in the wall cavity.

[cricketlegs]

The bench is 18" high. I also wondered if removing the Kerdi from the bench was necessary before using durock.

I'm considering adding a wall just past the bench, that would sit on the curb. That would add water protection and would allow a small shower door to be installed since it seems too small a shower to go without a door.

There are Schluter corners in each corner.