Questions on waterproofing tile walls for shower with floor pan.

HautingLu · 09-10-2009, 10:31 PM

I'll be putting in a new shower shortly, so I have a few q's to correctly waterproof it. Not doing a mud floor, just using a (white) 36x36 neo-angle pan, 2 tiled walls, and a glass enclosure (door). The rest of the bathroom will be tiled too. Using a NuTone in-line fan to vent.

From all the research, this is what I've come up with:
-40mil plastic liner on the studs. Should this go up in rows like roofing felt, or columns just against the studs?
-1/2" cement board
-Fill joints and seams with latex modified thinset.
-Redgard both (any) walls that will get wet, not just joints.
-Then tile, grout, and seal.
-Ceiling will probably be cement board, or greenboard with

Is the plastic barrier needed with RedGard, or just overkill? If needed, should it go over the shower pan lip and leave a weep hole?

What about under and around the pan. Do I need to do anything special if the floor in the bathroom may get wet (like stepping out of the shower)?

Thanks.

JazMan · 09-11-2009, 09:45 PM

Well....not quite.

40 mil liner is a shower pan membrane use to waterproof the floor and also goes up the wall 8-10 inches. You don't need tis since you're using a one piece molded pan.

The studs are covered with 4 or 6 mil plastic or tarpaper to act as a vapor barrier. However, this vapor barrier is omited when a surface membrane is to be used. So screw the backer board to the studs, no plastic behind it.

No need to install cement board on the ceiling, but you can if you are a masochist.

It's best not to use green board either, since GB is supposed to be installed on ceiling joists that are 12" o.c. Regular wallboard with waterproofing membrane will work best.

The pan gets installed per directions, waterproofing under it would do no good.

The bath floor is not required to be waterproof either. Stepping out of the shower while still wet will not require a membrane. But, you should dry off while still in the shower then step on a towel.

Jaz

HautingLu · 09-12-2009, 09:16 AM

Quote:

Originally Posted by JazMan

Well....not quite.

40 mil liner is a shower pan membrane use to waterproof the floor and also goes up the wall 8-10 inches. You don't need tis since you're using a one piece molded pan.

The studs are covered with 4 or 6 mil plastic or tarpaper to act as a vapor barrier. However, this vapor barrier is omited when a surface membrane is to be used. So screw the backer board to the studs, no plastic behind it.

No need to install cement board on the ceiling, but you can if you are a masochist.

It's best not to use green board either, since GB is supposed to be installed on ceiling joists that are 12" o.c. Regular wallboard with waterproofing membrane will work best.

The pan gets installed per directions, waterproofing under it would do no good.

The bath floor is not required to be waterproof either. Stepping out of the shower while still wet will not require a membrane. But, you should dry off while still in the shower then step on a towel.

Jaz

Thanks Jaz. I guess the plastic would be a bit overkill. I just wanted to make sure it would be 100% waterproof.

Two more questiona ---- what type of thinset should be used to fill the joints of the cement board before RedGard? And, I've read its recommended to leave the CB 1/8" about the shower (but over the lip, of course), then to caulk or thinset that area. Does that sound correct?

JazMan · 09-12-2009, 02:31 PM

You do not want 2 vapor barriers on the wall. It's not overkill to have 2, it will probably cause damage down the road if you do.

Use a modified thin set mortar for the joints/tape and to install the tiles over Redguard. Since it looks like you're shopping at the orange place, Versabond is good enough for most jobs, Flexbond is better.

You can caulk or thin set the gap between the cement backer and the shower base. Then use caulk in the joint after the tiles are set though. Are your shimming out the backer to clear the lip?

Jaz

HautingLu · 09-12-2009, 11:24 PM

Thanks again. Like I said, there's a lot of info out there so I wanted to make sure I was going to do it rigtht.

Last question...........

In the future I plan on putting in a claw foot wooden or cast iron tub. So the plan is to install a facet and a drain now under where the tub will be. Do I want to RedGard the floor area under the tub? Reason I ask is that the tub may have to drain onto the floor to reach the drain.....so it wouldn't be directly connected to the drain. Thoughts?

Thanks.

Bud Cline · 09-13-2009, 02:24 PM

Take it Jaz............

HautingLu · 09-13-2009, 09:43 PM

Quote:

Originally Posted by Bud Cline

Take it Jaz............

Not the best of ideas?

Edit: Jaz - yes, probably doing to shim to get the CB to clear floor lip.

JazMan · 09-15-2009, 10:26 PM

Lu,

Please don't let the future tub drain on to the floor as you stated. That will not work unless you pitch the floor to the drain area, and the tub is on your deck or in a barn.

Where did that idea come from?

Jaz

p.s. thx Bud

HautingLu · 09-16-2009, 08:33 AM

Jaz, the bathroom floor is actually pitched slightly towards the drain. I still don't understand why this is an issue if I RedGard all around it.

I probably explained it wrong. The tub will have a small drain tube doing directly down to the drain. When I drain the tub, there isn't going to be a huge waterfall......maybe like turning over a 2-liter of water right over the drain.

Anyways, not sure where the idea came from. My bathroom had a cast iron tub originally, but we ended up removing it. In the future, I want to put a wooden bathtub there and I figured I'd plumb for it ahead of time.

Bud Cline · 09-17-2009, 06:17 PM

Quote:

p.s. thx Bud

You are very welcome.

JazMan · 09-17-2009, 09:58 PM

Why not hook it up the proper way?

BTW, I have a contact in China that was trying to get me interested in wooden tubs they manufacture. How popular are they in North America, do you know? Any idea on the range of retail cost?

Jaz

HautingLu · 09-18-2009, 12:12 PM

Quote:

Originally Posted by JazMan

Why not hook it up the proper way?

BTW, I have a contact in China that was trying to get me interested in wooden tubs they manufacture. How popular are they in North America, do you know? Any idea on the range of retail cost?

Jaz

It was an after thought unfortunately. That's why I was asking on the proper way to seal around the drain. $2k for a cast iron tub was out of my budget for now. I expect a few trips to China in the future and was planning to pick one (or a few) up.

I don't know much about their popularity in the U.S., but I did a quick search and they go from 1k to 3k online. In China, retail stores stock them for a few hundred dollars. They also make some nice vanities and bathroom accessories. Plan is to stock up.

We already have one installed. The only 'issue' is the maintenance. You can just dump hot water in it if it hasn't been used. You have to fill it up with cold water and let it sit a few days. At least that's what the manual says. Other than, quality is pretty good.

But back to the original question: CB sloped to the drain and redgard under and around the tub (that may or may not get installed). Is this sufficient?