Gap between tub and durock (not lip)

megablok · 11-30-2011, 11:31 AM

hi everyone!
I'm re-doing a tub tile surround and ran into this problem. After finishing the Durock over a 6mil vapor barrier, I noticed that there is a one inch (almost) gap between the Durock and tub. The other two sides are fine; Durock stops 1/4" above tub lip.
I'm using a 1/2" porcelain tile with 1/4" v-notch trowel. So it covers 3/4" thickness, but there will still be a gap of 1/4" between tile and tub.
Is there any solution to this other than ripping out the Durock and reinstalling it on plywood board to account for gap?
Thanks!

Bud Cline · 11-30-2011, 11:43 AM

Your tile is only 1/2"? What 1/2" X 1/2" square or what?

What kind of tile adhesive are you using?

megablok · 11-30-2011, 12:18 PM

Hi bud,
The tile is 12x24, 1/2" thick porcelain. I'll be using topflex mortar to lay it.
Thanks.

JazMan · 11-30-2011, 01:30 PM

Quote:

I noticed that there is a one inch (almost) gap between the Durock and tub.

Too bad you didn't notice that before.

Quote:

I'm using a 1/2" porcelain tile with 1/4" v-notch trowel. So it covers 3/4" thickness, but there will still be a gap of 1/4" between tile and tub.

First of all you do not use a 1/4" V trowel for tiles like that. Secondly, the correct trowel, (probably a 1/4x3/8x1/4"), will leave a thickness of about 2/3 the size of the notch. So the trowel I recommend above will leave about 3/16-1/4" (3/8" depth), of thinset. However once you smish the tile into it, it'll add about 3/32" 1/8" max. You'll be lucky if it all adds up to 5/8", but I would want the entire tile inside the tub flange.

You should shim out the wall probably.

Jaz

megablok · 11-30-2011, 02:55 PM

Thanks Jazman. I will check the trowel this evening. I'm really not excited about removing the durock to shim the wall.

I am wondering if someone else had the same problem during the tiling process and did something creative!

Bud Cline · 11-30-2011, 02:58 PM

Hey mega,

This "gap" of which you speak? Is it a vertical gap from the top of the tub to the bottom of the cement board? If so that's no problem at all.

megablok · 11-30-2011, 03:26 PM

Hi bud,
Its not the vertical gap. Its horizontal gap. Its between the tub edge and wall. I have posted a picture under the "photos" link above - It is called the TubGap Problem...
Thanks!

Bud Cline · 11-30-2011, 03:38 PM

Yup, that's a gap, and a fine gap it is too!

When you add the tile to the wall and imagine a little thinset under the tile - how big will the gap be then? It may be caulk-able. Not the best of circumstances. I see why you wouldn't want to shim the wallboard but that's what should have been done even if it meant shimming the entire wall.

You could add another layer of cement board then deal with the edge of that board by cutting tile slivers to dress the edge.

You could also add another layer of cement board and use extra wide metal tile edging to cover that cement board edge.

Is it too late to move the tub a little?

megablok · 11-30-2011, 09:36 PM

Yeah. I had bought a 5/8" plywood to account for the gap. But in the hurry to finish, forgot to put it up. Aaah. What a predicament.

Cannot move the tub. The tile expert in the store recommended against double layering Durock.

I may just have to take it down and redo it.
Also, I have vapor barrier behind durock. Do I still need to do redguard?

Bud Cline · 11-30-2011, 09:43 PM

Quote:

The tile expert in the store recommended against double layering Durock.

WHAT ?
NONSENSE !

What "tile expert" are you talking about? I hope you aren't talking about Home Depot or Lowe's!

joecaption · 11-30-2011, 09:50 PM

We always use 1/4 lattice to shim out the walls then the tile board. Far cheaper then two layers of tile board.

JazMan · 11-30-2011, 10:43 PM

Quote:

We always use 1/4 lattice to shim out the walls then the tile board. Far cheaper then two layers of tile board.

That's great, but he needs to shim out at least 1".

Quote:

Yeah. I had bought a 5/8" plywood to account for the gap. But in the hurry to finish, forgot to put it up.

Plywood wouldn't have been such a good idea either.

Quote:

Also, I have vapor barrier behind durock. Do I still need to do redguard?

You should not have both. I believe the surface membrane is much better. I'd remove the one over the studs if you remove the board.

Please let us know where you found a "Tile Expert" at a retail store so we can commend them.

Jaz

megablok · 11-30-2011, 10:56 PM

@ bud
The tile "expert" at the tile store that is. LOL.
I may just take it down and put furring strips on it. Ugh.

Another question. Is the Redgard needed on top of the Durock if there is vapor barrier behind it?

Also, does the orientation of the Durock board matter? I have some of the boards mounted such that "Durock" reads vertically instead of horizontally.

Thank you!

Bud Cline · 11-30-2011, 11:21 PM

Quote:

Another question. Is the Redgard needed on top of the Durock if there is vapor barrier behind it?

Either/or, not both.

joecaption · 12-01-2011, 08:40 AM

The direction it's sitting does not matter, the screw heads need to be covered with thin set and the seams need webed tile tape over them set in thin set, sort of like when sheetrocking, Then seal the whole thing with Red Guard, Tile board is not water proof.