Tub/shower project

[tmppgh]

I am going to be tiling a tub/shower with marble and have some questions. I plan on using 1/2" cement board with a plastic vapor barrier behind it.

1. I am using a noble niche in the shower, does the vapor barrier need to "wrap" the back of the niche?

2. The noble instructions say to cut the cement board on the wall to create a hole for the niche, wouldn't it be easier to precut the hole prior to installing the cement board on the wall?

3. When I overlap the vapor barrier onto the tub, do I just hide the film with the caulking that will seal this gap?

4. There is a window in the shower, would wrapping this plastic and then taping all of the joints on the cement board be enough, or should I use some Redgaurd?

I am also tiling the floor, and was wondering if it is more pleasing to have a full row of tile at the door or at the tub?

That is all I can think of right now, but I am sure there will be more questions.

Thanks in advance for all of your help!

[cx]

Welcome, Todd.

1. Not usually feasible to get a good job that way. Best to just cut your moisture barrier to accommodate the niche and then waterproof the niche area with a liquid-applied membrane after installation.

2. I don't think Noble really gives a rats' patooti how you get the hole there in the correct location.

3. I like to allow the moisture barrier to hang out over the tub until time to tile the bottom row. Then you just cut the poly back flush with the wall and tile the bottom row.

4. Much like #1. You'll want to ensure you have the bottom sill sloped to drain and waterproof the whole window area with a liquid-applied membrane.


My opinion; worth price charged.

[Rd Tile]

1. Doeasn't have to.

2. If you know exactly where it has to go and the studs aren't in the way, either way.

3. I never seal it, probably a good idea, I just cut so it overlaps the lip.

4. You should have CBU right up to the window frame,leave about 1/16 to 1/8" gap, tape and Redgard it, then use 100% silicone after grouting at that joint.

Hope it's a vinyl framed window and not wood.

You have to lay it out for the floor and see how it works, you don't want a small cut anywhere.

What CX said, I type too slow.

[tmppgh]

Thanks for the replies.

And yes it is a vinyl window.

[Rd Tile]

When you tape off the window, leave a 1/8" gap up from the window joint, so the Redgard gets painted on the vinyl also, the tile will hide it and help in waterproofing that area.

[tmppgh]

Another question:

In the corners of the shower, do I caulk, thinset and tape, or tape and Redguard the cement board?

Thanks again.

[cx]

Todd, you should install that CBU per the manufacturer's instructions. If none came with the board, they are all available on the manufacturer's website.

Most call for filling and taping all joints with alkali-resistant mesh tape and thinset mortar.

But look up the instructions for your product. And let that get to be a habit for all new products you use. We recommend it frequently because manufacturer's instructions trump all other guidelines in the trade.

My opinion; worth price charged.