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PermaBase� Cement Board without waterproofing

Bongo
9 years ago

We just found out that our contractor used PermaBase Cement Board without any waterproofing membranes such as Kerdi. This was done in both of our bathrooms, and they both are already tiled and grouted. It looks like the thinset was applied directly to the board.

What should we do now? Do we need waterproofing? Do we have any other options besides the re-doing both bathrooms?

Thank you!

This post was edited by bongo15h on Mon, Jul 14, 14 at 9:39

Comments (18)

  • StoneTech
    9 years ago

    One acceptable method would be if he put 4mil plastic on the studs BEFORE the cement board. It is either THAT or use Kerdi, Hydroban or any ANSI 118.10 approved membrane OVER the board.

  • Bongo
    Original Author
    9 years ago

    I don't believe he used the plastic either (as I didn't see it) but will confirm for sure tomorrow.

    If there were no plastic used, what are our options?

    Thanks.

  • User
    9 years ago

    No waterproofing of any kind is rip it out now, or wait and rip it out after the water damage has been done and the bill is 2x as much to deal with that.

  • Bongo
    Original Author
    9 years ago

    Is it expensive to re-do? Can we leave the bathtub in place and plumbing fixtures while we are re-doing it? This was a total gut renovation - so everything was replaced and installed new at the same time. Do we only tear out the tile and install waterproofing over the board? Or the board has to be replaced as well?

    What do we tell our contractor? We still owe him some money but I can see him insisting that he did everything pursuant to our contract and up to the code. What is reasonable to deduct from what we owe him? We purchased all of our tile, do we deduct that as well or just eat up the cost ourselves?

    And I guess the most important question - how do we find another contractor who is knowledgeable about about this stuff? The person we used was highly recommended to us, so I just don't understand why there were no waterproofing used.

  • Bunny
    9 years ago

    I just had a gut and replace in my guest bath. My GC used Kerdi. I didn't take pictures of the Kerdi, but I'm pretty sure it went all the way to the floor, i.e., behind the tub, because I have tile that goes to the floor in front of the tub. The wall thickness behind the tile is the same all the way down to the floor.

    Is your contractor licensed? Did he pull a permit? My GC is licensed and we didn't pull permits. :) Is there any jurisdiction that says nothing is required? If he installed your tile knowing that there's nothing similar to what StoneTech has mentioned underneath, how can he say it's up to code? Does your contract spell it out?

    Good luck. I know how much time and labor goes into to doing a tub/shower surround.

  • Bongo
    Original Author
    9 years ago

    Yes, he is licensed, and our permit is still open. The contract's only reference is under paragraph titled "insulation" and it just says that in the bathroom mold and moisture resistant will be used. But prior to renovations, I gave him a list of what I wanted done and Kerdi was specifically listed as one of my requirements. I just assumed it was done until we discovered now that it wasn't.

    Is removing the bathtub necessary for this re-do?

  • PRO
    Joseph Corlett, LLC
    9 years ago

    bongo15h:

    Your contractor has to not only comply with local codes, he has to comply with the contracts he's made and manufacturer's application/installation instructions.

    Sit on that money until he does. It's the only thing we understand.

  • Bongo
    Original Author
    9 years ago

    Thank you al!!!

    Does anyone know how much something like this should cost to re-do?

  • Bongo
    Original Author
    9 years ago

    So its official, the contractor just confirmed that no additional waterproofing was used on either side of the cement board. He said that the cement board and thinset were sufficient to waterproof the shower.

    I can't believe it, we are now back to square one and have to re-do the entire thing???? Who does that?!?!?!? I am so angry and upset.

  • mayflower1032
    9 years ago

    I may be tearing my bathroom out too. Trying to figure out how water can get behind the Durock. If my research stands correct, water flows behing the Durock on the poly barrier. But my dilemna is how does the water get back into the bathtub? Opinions say you need caulk which will hold back the water. If water does not get back there or cannot get past the Durock, what is the purpose of these barriers? Can water go through grout, thinset, and cement board if just hitting on an angle taking a shower?

  • Bunny
    9 years ago

    mayflowers, you might want to visit the John Bridge forum and ask your questions there. They are real pros and can answer and explain anything you throw their way.

  • Bongo
    Original Author
    9 years ago

    Mayflowers, i think water should be able to evaporate back though the thinset, tile and grout. The purpose of poly barrier between cement board and wood studs is to prevent water going to the wood studs which will make them rot.

    When did you do your bathroom? Was it done by a contractor?

  • suzanne_sl
    9 years ago

    You asked if this can be fixed without removing the tub. Yes. It would be a matter of removing the cement board with the attached tile from above the tub. Unless this is the world's worst tile job, that tile isn't coming off the cement board any time soon, so it all goes together. You may cry, but they need to take a hammer to your new tile to get at the board underneath. It's unlikely that there is cement board down behind the tub. Most tubs (all?) are designed to be installed next to the studs. For the bit of wall in front of the tub, they use a skinny piece of cement board to cover that space.

    Do you need to remove showerhead, etc.? Sort of. You need to unscrew the fixtures from the underlying plumbing pipes and cap the lines until the work is done. Not a big deal.

    That tubs and showers need to be waterproofed as StoneTech described is not something known only to those in the know. The 18 year old kid in the tile isle at HD knows this, I know this, there is no way a contractor doesn't know this. My guess is 1) someone forgot to staple up the poly, which is a cheap and quick job, before they hung the cement board and they decided to forget it, or 2) he took a short cut and figured he'd be gone before you discovered the wall damage. In any case, you have a problem.

    Yes, the whole tile job needs to come down and done over. Having just done this same job (DIY) in our own bath, I would suggest that Kerdi is overkill for a tub enclosure, but you can if you want. We hemmed and hawed and finally went with HydroBan, but the poly is also acceptable. Grout and cement board are both permeable - there has to be a barrier.

    If all is right in the world, your contractor owes you for demo, materials, and re-do.

  • Bunny
    9 years ago

    It's unlikely that there is cement board down behind the tub. Most tubs (all?) are designed to be installed next to the studs. For the bit of wall in front of the tub, they use a skinny piece of cement board to cover that space.

    suzanne, I think you're right about that. I guess it would be in front of the tub flange, since you wouldn't tile directly on the flange.

  • suzanne_sl
    9 years ago

    Maybe this will help. This is when we had the tub in next to the studs and all the essential plumbing in. The plumbing is capped off waiting for tile before the final fit and attachment of the actual handles and such

    This is after we nailed up the Durock. Notice the 1/16" gap between the Durock and the surface of the tub.

    Here's the same wall painted with HydroBan and with the first bit of tile up

  • Bongo
    Original Author
    9 years ago

    Thank you!

  • suzanne_sl
    9 years ago

    P.S. The Durock isn't actually nailed in, it's screwed in. I was concentrating on the steps and current issues, but screw vs. nail is important. Sorry.