Wonderboard to Composite Shower Pan transition

[pgabriel]

Hi All,

Sorry, I know this has been covered before, I just can't seem to find that thread.....

I have a composite shower pan, it has a 1/4" or less flange that extends above the pan 1/2" on all sides except for the threshold. I have 15# roof felt on the studs. Once I install the pan, how does the transition from the wall get to the pan?

The wonderboard needs to stop above the flange, not go over it and down to
the pan lip? Otherwise it will look like my wife was right and I should hired somebody!!

Leave the wonderboard 1/16" (???, that seams small) above the flange,
bring the vapor barrier down over the flange and caulk to the pan and trim it,
then the bottom row of tile will sit flush with the pan, hiding the vapor barrier
(and the gap between the wonderboard and the top of the shower pan),
Caulk where the bottom row of tile abuts the shower pan?

[bbcamp]

Leave the wonderboard 1/8" above the flange,
bring the vapor barrier down over the flange and caulk to the pan and trim it,
then the bottom row of tile will sit flush with the pan, hiding the vapor barrier
(and the gap between the wonderboard and the top of the shower pan),
Caulk where the bottom row of tile abuts the shower pan.

[pgabriel]

Thanks Bob! I swear, I watch this forum just like TV. Great place!

[robhouston]

How about the same situation using Kerdi-------do you bring the drywall down to about 1/8" above the receptor flange, then bring the Kerdi down to cover the flange, perhaps using the adhesive Schluter sells in caulk tubes to adhere the Kerdi to the flange? When tiling, would one then use a bit more thinset to fill the gap under the tile at the flange?

Thanks,

Rob

[bbcamp]

Yep.

[pgabriel]

Sorry, Bob, just to be clear.....

I was going to fill that gap with a heavy bead of caulking. That way it can be replaced easily. Is it supposed to be filled with thingset? Pros/Cons?
And what kind a beer is required to fill such a gap?

[bbcamp]

I understood the thinset would be on the backside of the tile and against the vertical face of the flange to provide support for the protion of the tile that is not resting on the backerboard. You should leave a space between the bottom edge of the tile and the receptor deck for caulk.

[wurven]

Originally Posted by pgabriel

And what kind a beer is required to fill such a gap?

Works for me

Paul

[pgabriel]

Hi Bob,

Yes, I could do that, but if the flange is only 1/4" or (less)
thick and the wonderboard is 1/2 ", that would require a full
1/4" of thin set (which I guess would have to cure before
tiling)?

[bbcamp]

Peter, maybe I'm having a dense day, but the thinset you fill between the tile and the flange is applied at the same time as the tile. Cures just as fast as everywhere else, about 24 hours.

[pgabriel]

It's not you, it's me.



What's killing me is I *know* I've seen the exact pics of what I am talking about in a thread here and I just can't find the little bugger.

[pgabriel]

Okay borrowing a picture here..... (hop it comes out)

1. The distance from the top of the flange (green) to the top of the shower pan lip is about 1/2". If I hang the CBU on the studs, 1/8" above the shower pan flange, then there will be a gap 5/8" high.

2. The thickness of the CBU is 1/2" and the thickness of the flange is about
1/4".

This would make a gap 1/4" deep x 5/8" high x 36" wide. Filling that with thinset seems scary to me.

[John Bridge]

Hi Peter,

I don't know what size tiles you're using, but if they are over 3 in. square there is no problem in leaving the gap. I wouldn't even worry about filling it with thin set. I would just leave it vacant and grout the tiles over it. Caulk the tiles to the top of the tub deck. That's how it's done.

[pgabriel]

Hi All,

The project was progressing quite lovely....

Plumbing redone, vapor barrier up, CBU up, joints taped with thinset, niche framed. Just needed to order the tile and prehaps get around to installing it.

My wife called me at work this morning and asked me where I had put the
new shower head and handle (trim). I told her, then I told her I loved her and politely hung up.

After ten minutes I started to feel pretty sick. I am not sure why I didn't ask her what exactly she wanted it for or why. And in a fit of panic, ran back to
my desk and frantically dialed my house. There was no answer..... there
was no answer for about 35 minutes.

(If you can't handle pain, please stop reading....)

Um........ how long will CBU remain wet if, let's say...... someone decided to take a shower in shower that was only 1/2 way complete? Will this dry out? Or am I pulling it down and starting over?

And to those who are going ask, the shower curtain was manufactured with contractor grade black trash bags and duct tape.

[Rd Tile]

It will dry out, don't worry, get a sheet of poly and tape it up over the walls, you WILL need it over the new tile and then again after grouting if this is the only shower you have.