Mongo just gave you three of the best suggestions-- Durock, Wonderboard, or Hardibacker.

Bill,

Could you look at my posting from this morning? I had a quick question for you. Thanks, Tammy

I'm sorry-- I read it, and then got sidetracked by pupwhipped's post!! You're better off to use the sheets horizontally. You won't waste nearly as much material.

Would these be the steps....tear down green board, install tar paper, install cement board using "rock-on" screws, lay tile?

That's it. :-)

we are to use fiberglass tape and use thin-set instead of joint compound?

Correct.

oooops, sorry about that Bill and Chuckwagon. Sometimes I sidetrack/hijack my own self! REALLY hate when I do it to others, though. I'm going to assume the best here in my situation...DAP is for ceiling and other walls of my small bathroom. Sure seems to be a heck of alot of it, though?? Then they will use Durock or similar for shower area. I'm pretty darn sure they will be doing that NOW! Hubby is a "Polly Anna" type. I'm going to try and be one, too, and not assume the worst in every case.

Chuckwagon, I hope you get your situation resolved quickly and to your satisfaction, and I thank you for posting this topic. Good luck to you. And, as always, thanks to Mongo and Mr. Bill.

We put up a vapor barrier, then DensArmor Plus, then hardibacker, then tile. The guy at Lowe's said to use DAP instead of greenboard, though in his defense, he didn't tell us to use it as tile backer. And later, when I was buying tile and talking to the Lowe's tile guy, he told me that cement board got screwed straight to the studs (what I wouldn't have given to have avoided the every-six-inch screwing into the DAP that I did). So I don't blame Lowe's for anything.

Ah, the life of a DIY-er before she discovered GW. Perhaps our shower wall will dissolve someday...at this point we'll cross that bridge when/if we get to it.

I hope not. That whole bathroom came out so beautifully!! I mean, that was really exceptional!

Two things...

Weedy, I'm really sorry, I hope I'm not causing you worry. I just mentally matched up your partial pic above with the finished pics I remember seeing weeks ago, and just as Bill wrote, your bath is one of the nicest I've seen! I love your bathroom!

pupwhipped, please please please...don't assume that your installers are not going to use the DAP in the wet area. If there was cement board on site, then that's a valid assumption. But with no CB on site and a large stack of DAP?

Go on the offensive. Talk to your builder now, and also write a large sign and hang it on the wall that DAP will NOT be used in the wet area as it does not meet building code. Despite them "always doing it this way and never having a call back", they will not use DAP in your shower. And do make sure that they install either 6-mil poly or lapped tar paper between the cement board and the wall framing (studs).

Mongo

Thanks Mongo. I'm on it like white on rice. I'm a bit of a control freak (has anyone noticed?) and I won't stop now. My GC is used to it...or rather my hubby is used to me confronting him about problems and then having him confront the GC. HA! Funny, my GC has suggested that I use some kind of marble stuff on the floor of the shower as he said that will never have a leak. I really want tile. Guess he is somewhat concerned with preventing leakage problems, anyway.

I will stay with it. And don't worry, nothing gets done in this remodel if Momma ain't there. Control Freak Momma, that is. Hmmmmm, maybe that's why this whole remodel is taking for"freakin"ever. Thanks again to you and all.

Tell him to get "Kerdi-ized"!! He'll never see another leak again!!

Bill & Mongo: Don't fret about making me fret. I'm not losing sleep over it or anything, as I'm busy wainscoting the dining room. I realize that not every imperfectly-constructed shower ends up with internal water damage, and we may never have a problem. If we do down the road, well, we'll deal with it. And earlier threads had cued me to the fact that we didn't follow protocol on everything, so this isn't a new discovery.

I would much rather you guys be honest so we can all learn from ours and others' mistakes than try to tread lightly to avoid distressing us. Thanks. :-)

I'm compelled to write a little "Fact Sheet" about shower construction and hand it out to the managers at the local home centers so they can distribute it to their employees.

It brings me back to a time a few years ago when I overheard a Home Depot employee telling a customer that he can wire a breaker in his sub panel with 12ga lamp zip cord.

Oy!

Mongo

Thanks very much folks. I thought this "little bathroom fixup" was going to be a piece of cake...silly me!

mercurygirl-- There's an old saying-- "Anything worth anything isn't easy!"

Ok, the green board is down. We are getting ready to put the 6 mil poly to the studs now. We had a quick question, do you leave a space at the bottom of the hardibacker or does it sit on the tub? There is a 7/8 inch flange around the tub. Do you put it above that or down to the tub? Thanks.

Let it rest on top of the flange.

If you rest it on top of the flange, what happens with the 7/8 inch under the hardibacker? Do you tile down to the tub (spacer between tile and tub)?

Thanks for quick answer.

If the tiles are large enough, you can let them hang over the 7/8th" void. Hold the bottom course of tiles off the tub and caulk the gap between tile and tub.

If the tiles are not large enough, you can fill that 7/8th" gap (cover the flange) with thinset, then tile over the CB and the thinset fill. Still hold the tiles off the tub and then caulk the gap between the tiles and the tub.

Mongo

Mongo

Thanks Mongo.

??? - how long do you have to wait after you use the thinset over the tape on the joints? Is there drying time before you can begin tiling? Thanks again.

"...how long do you have to wait after you use the thinset over the tape on the joints?"

That depends.

You could do the mesh tape and thinset the joints as you tile. The problem is that as you notch thinset over the cement board, you might catch and lift the mesh tape.

The easier way would be to hang the cement board, then mesh and thinset the joints. Let it cure overnight, then the next day come back and tile the walls. This second method paces the job a bit more and give you a chance to admire your handywork step-by-step.

When you thinset the joint, remember, this isn't drywall. You don't want a noticeable hump across the joint. You want to keep the joint in plane with the face of the cement board. Thinset is not Easysand joint compound, in that if you end up with a build-up, you don't sand it down. You curse!

Mongo

Your best bet is to use the self sticking mesh tape, and then when you spread your thinset to set the tiles, you'll be killing two birds with one stone.

Problem.....we have installed the hardibacker and we are running into a slight problem. The 1/2 cement board is actually 3/8 in and the 1/2 green board is measuring more like 3/4. Can we compensate for this when we us the thinset and tape? Is this going to cause major headaches?
Thanks guys!

Hi Bill,

One more. My contractor neighbor told me that a vapor barrier is only needed on exterior walls as there is no temperature difference on the interior walls. True?

Thanks!

Chuck-- See if you can put a layer of 1/4" over the 1/2". Start out by buying a single sheet, and seeing if it'll work. If it does, then get the rest of what you need. If it's still not enough, you can always feather in the rest with some thinset.

mercurygirl-- Tell him he might want to check a copy of the TCNA Handbook. He'll find that the entire enclosure must have a vapor barrier behind it. If he doesn't know what the TCNA Handbook is, you may want to find someone else to do your tile.

Thanks again. The neighbor isn't doing the tile.
Why do you have to cut slits in the barrier where it covers insulation? How many?

You ahve to cut slits in any existing vapor barrier because with back to back vapor barriers you'll end up causing condensation between the two-- what's called a moisture sandwich-- which will do more to PROMOTE mold and mildew than curtail it. As for number of slits, I've never really counted I guess one slit every 4-6 inches would do.

More questions for you all. We've received several bids for having our master shower retiled - each bid has included in it hardybacker board. I had a guy give me an estimate on doing cultured marble and his bid says sheet rock. Shouldit also be hardybacker?

I'm just confused about this right now. Of course the marble guy says it will never leak - well.............there aren't seams like tile but there are seams. I believe it could leak. Am I missing something here?

Eaglemom- the solid surface panels are usually installed with silicone which doesnt adhere as well to backerboards like it will to regular ol' sheetrock.

When the panels are installed, they should be set in a fresh bead of silicone where it meets adjacent panels and the pan. This provides a better seal than just caulking after everything is assembled.

With that said, I still do a hybrid method of drywall and Kerdi-band... I run a strip down inside corners and along the top of the pan. If the silicone ever fails at the seams, the water will stop at the Kerdi-band.

Bill: sorry it took so long to get hold of my atty friend. He sued one builder in California; the case settled with the greenboard people paying a token or nominal amount. His position was that greenboard is water resistant but not waterproof, the good tile guys know that, and the IBC (UBC?) was changed in 2006 because of those problems. He says he has boxes of private doc's from US Gypsum and the like. He likes to file class action cases all over the country and did his best to hint that if anyone wants to be a class representative in another state, he will travel. As an atty myself I must note that I'm not soliciting anything. I don't do class action lawsuits and I don't practice outside of California. I just want to fix up a powder bathroom with granite left over from my kitchen :)

IRC

(7 posts down, up above)

The problem is that as soon as the green sheet on the outside of the wallboard is breached (as in cut, or screwed thru) it's no longer water resistant.

I have the very same problem with Denshield.

Can someone please explain if we need a vapor barrior over Durock or Wonderboard or Hardibacker in a shower area? Also, is greenboard needed on walls of a bathroom that are not directly exposed to water? in other words, the non-shower areas? Currently, all the walls of the bathroom (the ones where water never gets) are covered with Pepto Bismol pink tile that is coming down so do i replace these with greenboard or just regular drywall? the greenboard evidently comes in different sized sheet than the regular drywall so we have a small area that is not going to be covered unless we just do baseboard at bottom over this space or unless we just use regular drywall. Is greenboard still recommended over regular drywall in the nonshower areas? Even though they don get wet, I'd imagine there is some condensation or whatever since it is a bathroom. Many thanks for your replies.

Vapor barrier needs to go BEHIND the cement board, either 6 mil polyethlene or 15 pound tar paper.

As for the greenboard. I'm not sure if it's code or not, but I DO know that any bathrooms I've ever been in (and that's a considerable number) have always been greenboard throughout, with the exception of the shower area.

iam replacing my old tub with a new one. my problem is the new tub is a half inche smaller so i need to build up behind the hardibacker a half inche. what should i use?any help whould be usefull.
thanks

You can nail or screw strips of 1/2" plywood to the studs before you install the Hardi board.

http://www.gp.com/build/product.aspx?pid=4684

Or you can use Denshield, as jdplumb has suggested. You'd still need to use the strips of plywood, though, to builkd it out.

Gosh, I wish that I had read (and understood!) this post before the house (a new build) was finished.

I just posted re water on the tub deck ending up on our bedroom floor as well as down thru a kitchen pot light.

Off the phone with the builder - there is no waterproofing around the tub (plywood deck, thinset, tile), and the tiled shower in the kids' bathroom has green board behind it. This is up to code in my neck of the woods. A pain in the neck, though, for us to redo (as much as I wanted an excuse to use my new wet saw). A pain and expensive.

Now I'm wondering what's under the floor tile...

Greenboard has been prohibited as a tile backer in wet areas by IRC code since Jan of '06.

It was prohibited by builders with a conscience long before then.

Mongo

Miles ahead, I guess, of our code (I'm in Ontario, Canada). Crumb for me.

i have read that hardiebacker is better then greenboard to lay tile on tub/shower a friend had is done they use both first the hardibacker then greenboard over it then they lay tile is that a good idea to use both and if you use both which goes first or it's it better just use the hardiebacker and to lay the tile you lay on the wetside or and the other side im new at this have never remodel my bathroom before

No greenboard in a shower, period. Not by itself, not over durock, not UNDER durock. It does not get used. Period End of story.

IRC Greenboard Code:
The 2006 International Residential Code (IRC) states in
Section R702.4.2 that "Cement, fiber-cement or glass mat
gypsum backers in compliance with ASTM C1288, C1325
or C1178 and installed in accordance with manufacturersÂ
recommendations shall be used as backers for wall tile in
tub and shower areas and wall panels in shower areas."

The 2006 IRC also states in Section R702.3.8.1 that
"Water-resistant gypsum backing board [Greenboard] shall
not be used where there will be direct exposure to water."

Not much room for ambiguity there.

Since were bringing this thread up again, and it is all great info. I just want to clarify please... Bill you mentioned showers on exterior walls that have insulation installed to make slits in the paper so it does not make a vapor sandwich. I understand this, in fact mine is all ripped up from the demo and I was going to replace it cause the paper is torn but now I figure,,, one less job I have to do.

Now I still have to install something on top of my studs before the durock right? How is this done and is it done floor to ceiling? I am guessing tarpaper is roof felt? I am thinking I will go with the roof felt instead of the polly because I have seen plastic just deteriorate with age and think I will avoid that pit fall.(please correct me if I am wrong and generalizing) What pound roof felt should I use and how wide does it come? I am familiar with ones that are 3 ft wide. How do you handle the gaps or do you lay it like roofing starting at the bottom and working your way up like shingles? Meaning from right to left around the entire shower on bottom and then move up on the wall and do the same but have the next one over lap the bottom and do this till you get to the top. If this is the way it goes, how do you attach it and 2nd how much do you over lap? When you get to windows how do you handle the joints there? Does this get done before or after the floor prep? Now I am thinking the shower wall stuff has to fall overtop the shower pan stuff right? Thank you in advance.

Now I still have to install something on top of my studs before the durock right? How is this done and is it done floor to ceiling? I am guessing tarpaper is roof felt?

Yes, using a staplegun, yes, and yes. :-)

What pound roof felt should I use and how wide does it come?

15 pound, and 39".

or do you lay it like roofing starting at the bottom and working your way up like shingles?

Yup. :-)

If this is the way it goes, how do you attach it and 2nd how much do you over lap?

I answered the first part already, and as for the overlap, an inch or two is sufficient.

When you get to windows how do you handle the joints there?

You simply cut out the area taken up by the window. Keep in mind-- this isn't meant to be a waterproofing-- only a vapor barrier. This is one of the reasons why you see Mongo and myself touting the Kerdi so much. It IS a waterproofing.

Does this get done before or after the floor prep?

It's the next step after situating the pan liner, and yes, it does get tucked into the liner.

First! thanks Bill you don't know how much you are helping me right now. This DIY do together project is now my project so I thank you sooo much.

It's the next step after situating the pan liner, and yes, it does get tucked into the liner.

Sorry I want to be clear on tucked "into" do you mean behind the liner for the floor?

I will definitely be doing Kerdi!

Sorry Bill just want to do it right and I am sorry to say there are probably a flood of Q's on the way. But if flooring comes before this I will be looking over all the notes on that. I am working on getting the roughs in situated now. Thought I could do them myself but I think I have to get some help in here for that. I have shark bite connectors and they seem pretty simple but when I purchased the reducers that nipple end of it is too short to use the shark bite so I am stuck. I will post over in plumbing and see if someone can give me pointers for that.

Not a problem. It's a good thing you told me you're doing Kerdi. Scratch the vapor barrier. With the Kerdi, it's not needed. Good thing, too, because with Kerdi, the Kerdi (which is surface applied) IS the liner.

Ok, and that gets put over top the durock which gets installed right over the studs, which is over the torn up insulation that I don't have to replace. Did I get it?

Correct.

Now, see? That didn't hurt a bit. :-)

Thanks Bill!

"....After some conversation with the instruction, he felt that the green board would be okay for this bath (only DH uses it) but in the future we should have the hardiebacker installed. Is this correct?...."

The age old question. Which is better.

Company's advertise the use of drywall as an approved backboard not because it's a good choice but because it is a fast choice. A cheap choice. These allowances sell products they do not build better showers. Understanding this and understanding that you can build a better shower without is an important step in the shower building process.

So Which is better? This is a trick question because both are poor choices for a shower or a tub shower installation. Green Board or moisture resistant drywall should not be used in any shower build if you ask me - regardless of how many company's allow it.

Hardi Backer is by far better than Durock but not as good as Wonder Board Lite. This I think is todays only decent choice in shower backer panels.

In todays rushed building world steps get skipped and showers are built every day with little to no thought to water migration. The question above so common and coming up all the time. Which is better.

The truth is - they both suck.

Wow....an exhausting thread. Bottom line is that Greenboard is not and should not be used in a wet area. It is about "Half a spit" better than drywall...but not by much. Trust this, it WII fall apart if not put up correctly. Just use regular drywall and clad it with Kerdi. No leaks, no issues, no problems. Easy-Peasy.