Tub/shower Surround

RadRemod

Let me preface this question by saying that I generally sub out any tile job over a sm bath floor to my tile guy. However in this case he is booked until December and the homeowners want the job done before Thanksgiving. So instead of risking using a new tile guy on the job I'm going to do it myself. I'm confident in the quality of my work but unlike you guys that do it day in and day out I'm slower at it!
Here's my question:

I have normally just used 1/2 conc board over the studs, mortared and taped the seams, then tiled grouted and sealed. After doing some research I'm thinking of adding Customs Redgaurd on top of the concrete board as an extra precaution. Is this over kill? will this cause any adhesion issues with the mortar and tile?

naptown CR

Is this a wet area or a steam shower
I have used redguard in steam applications before but not in a standard tub/shower.
I do however install 6 mil plastic behind cbu and thinset the tile to it.
redguard is a good product and should not create adhesion problems

angus242

OVERKILL???

It's a necessity! You're tiling a wet location. You need to waterproof! A liquid membrane is the bare minimum I'd use. Actually, I use Kerdi (or any fabric membrane). Using a liquid membrane, you need to follow the instructions carefully. Most have a minimum thickness you need to achieve before it's considered waterproof. Also, corners are a bitch. You will probably need multiple coats there and on any seams.

RedGard is specifically made for your application. Tiling over it is what it's designed for.

You also need to pay very close attention to where the CBU meets the tub deck. Check with the manufacturers of the tub and CBU to see what materials they approve for that joint.

__________________
Angus
L+M+O+P=C
"Promise only what you can deliver. Then deliver more than you promise"

RadRemod

I forgot to add that I also have used 6 mill poly on the studs behind the CBU. But was wondering if this is even nesesary if I use a liquid membrand on top of the CBU?

angus242

If you completely waterproof the CBU (walls), no. If you liquid membrane just screw holes and seams, yes.

__________________
Angus
L+M+O+P=C
"Promise only what you can deliver. Then deliver more than you promise"

RadRemod

I have seen the Kerdi products used more and more on TV lately. Especially on the Holmes show! It seems to be very slow in catching on over here in Salem, OR though. I called around to the local tile supply shops and they didn't seem to sold on it yet?!? I'd love to be able to see it used up close but might just have to use it on my own house to do so!

angus242

Kerdi has been in use since 1987

You can order online. Here's a popular site:
http://www.tile-experts.com/products.asp?id=49

or

Visit the Schluter website and locate dealers in your area.

__________________
Angus
L+M+O+P=C
"Promise only what you can deliver. Then deliver more than you promise"

RadRemod

Do I notice a hint of sarcasm? Did you start using them in 1987?

angus242

Nope!

I started using Kerdi 3 years ago. I know a few guys that have been using it for almost 10 years.

__________________
Angus
L+M+O+P=C
"Promise only what you can deliver. Then deliver more than you promise"

jarvis design

I've been using Kerdi for over 5 years and won't do any job without it.

__________________
Bathrooms Built for Life.
www.JarvisDesignBuild.com
519-495-4062

kevjob

Using kerdi for 4 years now and won't ever use anything else.

__________________
Kevin
Basement Finishing Highlands Ranch Colorado
Littleton Colorado, Basement Remodeling
Kitchen Remodeling Denver

R&D Tile

Showers with tiled floors.... Kerdi.

Tub surrounds and fiberglass shower bases.... DensShield and Redgard the seams and nail heads.

RadRemod

What do you guys do if the tub flange sticks out approx 1/2" in from the studs? The guy before me used green board and then hot mudded the gap! I was thinking of either furring out the studs with 1/2 inch ply so the CBU can overhang it. Or using some 1/2 z flashing to over lap the flange then butting the cbu up to it and covering both with the tile. Any thoughts?

R&D Tile

You just fir out the studs and hang your 1/2" backerboard, no plywood or greenboard.