Fox and other bathroom waterproofing gurus

[decoraholic]

Anyone up for a little bathtub/shower waterproofing discussion?

We're installing a new tub/shower combo with a tile surround, and I've been reading up on using moisture barriers with cement board (Durock, Hardibacker, etc) and everything I've read overwhelmingly says to use a moisture barrier of some type to protect the wood studs and keep water from getting behind the wall. The problem? Our local code just says to follow manufacturer instructions when installing cement board, and the cement board manufacturers say to follow local code on waterproofing. A vicious cycle. Since our local code is so vague, nobody seems to want to use anything but cement board to waterproof a tub surround.

We're considering hiring someone to do the tile surround above our tub, but it is seemingly impossible to find someone who thinks a moisture barrier is needed with cement board. Ugh! I tell you, these are not just handyman types, they are licensed plumbers and contractors who are highly rated on Angie's List.

So because of this, we're likely doing it ourselves, since we want to find someone reasonably priced and competent, an impossible thing apparently . Has anyone done a tub surround? Thoughts on vapor/moisture barriers? Which kind did you use?

[cajungal]

Do they refuse to use the moisture barrier if you request it?

[bunnymendelbaum]

My husband is doing it, so I haven't read up, but we are using the Schluter Kerdi system. Here is a link to the brochure/installation guide.

www.schluter.com/media/ShowerHandbookENG2012.pdf

[decoraholic]

Dec 6, 2012 15:37:16 GMT -5 cajungal said:

Do they refuse to use the moisture barrier if you request it?

Not exactly refuse, but they just insist it isn't necessary. I kind of lose faith in them after that, because I just worry that if it's not something they normally do, would they do it right, and what else do they cut corners on? If I have to watch over their shoulder the entire time, I may as well just do it myself, lol.

[decoraholic]

Dec 6, 2012 15:38:33 GMT -5 bunnymendelbaum said:

My husband is doing it, so I haven't read up, but we are using the Schluter Kerdi system. Here is a link to the brochure/installation guide.

www.schluter.com/media/ShowerHandbookENG2012.pdf

I've heard good things about Kerdi, espeically in stand up showers. Are you guys using this for a tub surround or a shower? I'm trying to decide if messing with the Kerdi membrane is worth it for a tub surround.

[bunnymendelbaum]

We are using it for a shower only! I should have read more carefully!

[cajungal]

Dec 6, 2012 15:48:57 GMT -5 decoraholic said:

Dec 6, 2012 15:37:16 GMT -5 cajungal said:

Do they refuse to use the moisture barrier if you request it?

Not exactly refuse, but they just insist it isn't necessary. I kind of lose faith in them after that, because I just worry that if it's not something they normally do, would they do it right, and what else do they cut corners on? If I have to watch over their shoulder the entire time, I may as well just do it myself, lol.

Makes sense. I'd feel the same way. I don't know anything about it, but I do know our builder used a waterproof barrier in our tub surrounds and I believe also the upstairs bathroom floors. Seems like a standard practice.

[hbomdiggity]

We did a tub surround diy and used kerdi with cement board.

[FoxInFiji]

Yeah I wouldn't be paying someone to remodel my bathroom if they don't think waterproofing is necessary. Keep looking until you find a competent tiler. I haven't used Angie's list but it sounds very hit or miss to me. Besides the people giving reviews are probably just people like "oh I have a pretty bathroom" not understanding a thing about codes, waterproofing, or best practice.

Cement board is not waterproof. Cementious grout is not waterproof nor is natural stone tile if you're using that. Showers get wet. Water will get behind the tile and grout to the cement board. Eventually it will get behind the cement board as well and then you have big issues. It's not rocket science. For a small amount of money and time you can ensure you don't have mold, warped wood, and a wet ceiling below by just waterproofing.

Cheap traditional waterproofing of a shower/tub combo would be to just use roofing tar paper stapled to the studs before cement board is installed. It's not fully sealed and it only does a half ass job. A full sheet of plastic behind the cement board can be used instead for a better job but it's still not great. Modern waterproofing is much better. It is applied on top of the cement board keeping it from ever getting wet in the first place. Unlike drywall cement board can get well but it shouldn't stay wet for any length of time or it turns to mush. So if you have one area that doesn't drain well or dry out your entire shower surround is compromised and will lead to cracked tiles, grout, and leaks. The two ways of waterproofing to keep the cement board dry is thinset on plastic sheets or paint on waterproofing. Kerdi is a plastic sheet with fuzzy backing that you thinset onto the whole shower area. Where ever you have a seam you need to add another strip of Kerdi on top with the precut rolls they sell. If you're doing a niche it gets a lot more complicated and you need to buy premade corners and add a 3rd or 4th layer of material. It's not hard to do but all of this layering adds thickness behind your tiles creating an uneven surface that is hard to tile over and keep your tiles level.

The paint on waterproofing is much easier in my opinion because it's much thinner an a breeze to paint and tile over. Redguard and Hydroban are the two popular paint on waterproofing systems. Redguard can be found at HD and Hydroban can be ordered at Lowe's or a Laticrete dealer. You paint a layer on the corners and seams of the cement board first. Any big gaps need to be covered with a hydroban fabric or thinsetted (and dried) first. Then you paint the field, repaint the seams, and repaint the field. It's like double the layer of waterproofing throughout and quadruple in the seams and corners yet it doesn't add near as much thickness as Kerdi does. All you need is 1 gallon for a shower tub combo and that costs less than Kerdi + thinset does. A gallon of Redguard is only $45 at HD. We used Hydroban for both our shower tub combo and our walk in shower. It's more expensive at $70 a gallon but it also comes with a 25 year warranty (and they will literally come redo your entire shower if it ever leaks) if you use it along with their top of the line modified thinset.

HTH

[decoraholic]

Great info as always Fox . You guys definitely do your research and I'm glad to hear you went with the paint on type and found it easy to use. One contractor did mention using tar paper, which was at least a step up from the ones that said they don't use anything. Nobody has mentioned using Redguard or other paint on waterproofing, probably because of the drying time involved. Gah. This seems like one of those "if you want it done right..." scenarios. Here we thought we we would treat ourselves to having a pro come do some of our bathroom renovation, and it's turned out to be a bigger pain than anything to research and find a good contractor.

[FoxInFiji]

Well you could always have the contractor install the cement board and then ask for a day or two for you to paint on the waterproofing. It's seriously just thick paint. You just brush it on (you can roll it too but you waste more product that way). Buy some cheap brushes because you can't really rinse it out when it dries.

Also note many contractors when you ask them to use the Redguard product will just paint the seams of the cement board and leave the middle. They use less product that way but you would still need to have waterproofing behind so you really should just paint the whole area.

Have you tried asking around or just randomly calling contractors from Google/the yellow pages? I can't believe no one would do this in your area! That's sucky.

[lys]

Ditto - use the Schluter system - it rocks.

[decoraholic]

Dec 7, 2012 14:27:00 GMT -5 FoxInFiji said:

Well you could always have the contractor install the cement board and then ask for a day or two for you to paint on the waterproofing. It's seriously just thick paint. You just brush it on (you can roll it too but you waste more product that way). Buy some cheap brushes because you can't really rinse it out when it dries.

Also note many contractors when you ask them to use the Redguard product will just paint the seams of the cement board and leave the middle. They use less product that way but you would still need to have waterproofing behind so you really should just paint the whole area.

Have you tried asking around or just randomly calling contractors from Google/the yellow pages? I can't believe no one would do this in your area! That's sucky.

We've really been getting quotes on bathtub installation, and then while they are out we get a quote for tiling if it's something they do. We've been on the fence about having someone else do the tiling vs DIYing it (we're definitely having someone do the tub and plumbing) and haven't gotten quotes for just tiling yet. We have had a range of contractors give quotes for the tub and tile from big kitchen and bath remodeling companies (way too expensive) to smaller time general contractors to regular plumbers. All are licensed and insured and say they do both tubs and tile. We didn't ask all of them about vapor barriers but when we did it was surprising to hear their answers. I frankly stopped spending too much time questioning each of the contractors when they came to give quotes because they would either not get back to us with a quote or the quotes were coming in way way too high, like $10K to install a tub, tile surround, and tile floor. Or we just didn't like them for whatever reason (personality, made us uncomfortable, etc). It felt like a waste of my time and theirs to spend 45 minutes talking about the bathroom if there was no chance we'd go with them because of the price. So we started taking the approach of just going over the basics about what we wanted, then if they came back with a reasonable quote, then I'd call/email with more questions.

I'm sure we could probably find someone if we start calling around enough. This whole hiring a contractor thing is a tiresome process .