Lots of questions about drywall and bathrooms - Contractor Talk - Professional Construction and Remodeling Forum

nobody · 02-18-2006, 01:54 PM

Hi everyone! I am a first time poster but have lurked here for a while! I am a novice when it comes to drywall but am willing to try anything. This is a great forum and everyone seems very helpful! Enough butt kissing.

I have three questions about hanging drywall in a small 5' x 10' full basement bathroom. I am installing a tub with a shower head. My first question is, can I transition hardi backer to green drywall about 6" away from the tub and overlap the first columm of tiles over the drywall and hardi backer? I want the paint to go on the drywall but not the hardi backer. Second, should I use plastic on the walls that are along the concrete foundation wall? I am using R9 insulation with a vapor barrier along the same wall but I wanted to stop any drafts if possible. I think one of the posts I read on this site said not to use plastic, and another said to use plastic. Just trying to find out the best way. Third, another post on this site stated not to use greenboard on the ceiling of the bathroom. It would eventually sag due to it's own weight. I have already put greenboard on the ceiling above the tub and glued it but I am willing to take it down and put something better up.

That's alot of questions but thanks in advance. Be kind, I am new at this.

Glasshousebltr · 02-18-2006, 02:14 PM

First: I wouldn't lap much, or the grout will work loose at the area under the drywall.

Second: It's best to use plastic.

Third: I use greenboard on bath cielings all the time, never had a call back for it.

Bob

Tom R · 02-18-2006, 05:54 PM

Probably me that said no greenboard on the ceiling, - - it's against code on ceilings (unless you use 12" O.C. ceiling joists), - - reasons being it 'can' sag from it's own weight, and it is less impervious to steam and humidity than even normal drywall.

Like Bob says, though, - - that doesn't necessarily mean you 'will' have a problem.

Steve Unkie · 02-18-2006, 07:22 PM

Tom,
Is this a local code, I have'nt heard this before. I will check my area to see.
If it is less impervious to steam and humidity then why is it the recommended wall covering for bathrooms?

I learn something new everyday, but this one surprised me.

Steve Unkie.

Greg Di · 02-18-2006, 09:20 PM

USG has pulled its certification for green board as tile backer in wet areas. Look it up. So many guys continue to ignore this fact.

Old school guys will continue to use greenboard until they can't buy it anymore. The more progressive guys have long ditched it.

DensArmorPlus is harder to work with, but much better overall for a bathroom.

DenShield will make you forget how to say "Hardibacker or Cement Board" the first time you use it. I kid you not.

**Teetorbilt** · 02-18-2006, 09:26 PM

We're using purple board here, anybody else?

Mike Finley · 02-18-2006, 09:34 PM

Quote:

Originally Posted by Greg Di

DenShield will make you forget how to say "Hardibacker or Cement Board" the first time you use it. I kid you not.

Hey, elaborate on that. I went from cement board to Hardi backer and thought that was a big improvement!

Tom R · 02-18-2006, 09:56 PM

Quote:

Originally Posted by Steve Unkie

Tom,
Is this a local code, I have'nt heard this before. I will check my area to see.
If it is less impervious to steam and humidity then why is it the recommended wall covering for bathrooms?

I learn something new everyday, but this one surprised me.

Steve Unkie.

Hey, Steve, - - hmmm, - - I'll have to check, - - it's been (at least local) code for so long I don't even remember.

It is (or was) recommended 'wall' covering, - - correct, - - but never recommended 'ceiling' covering, - - basically because steam rises is why.

At present, - - it is no longer even 'recommended' for walls, - - and is no longer even 'permitted' as a tile backer (in wet areas).

It has, IMO, - - basically become the 'scape-goat' for shoddy workmanship by today's 'rip-n-run' contractors.

You'll probably see from the next 50 or so posts, - - that's definitely not the 'popular' opinion.

Tom R · 02-18-2006, 10:17 PM

Quote:

Originally Posted by Greg Di

USG has pulled its certification for green board as tile backer in wet areas. Look it up. So many guys continue to ignore this fact.

Old school guys will continue to use greenboard until they can't buy it anymore. The more progressive guys have long ditched it.

In actuality, - - 'old school' guys DON'T use greenboard in wet areas, - - but 'new-school' guys will CONTINUE to say they do until the customers just 'won't buy it anymore'!!

Real 'old-school' guys have always continued to use 'regular' wall-board, - - part of the reason being that they didn't trust the 'new-fangled' product 'claims' of 'greenboard' at the time, - - and guess what, - - they were RIGHT ALL ALONG!!

That's part of the reason, too, why the 'old-school' guys are still somewhat SKEPTICAL, - - 'especially' when their 'tile-on-wallboard' methods have lasted for decades, - - and most often 'right through' the 'short lifetimes' of many of the newer products that have had much more claim than climax!!

Tom R · 02-18-2006, 10:34 PM

By the way, - - that 'rant' was not directed at you, Greg, - - your wording just gave me the excuse I needed to spew it!!

Obviously, - - I'm not big on products that have not stood the test of time, - - I still like 'copper' supplies, - - 'plywood' sheathing, - - 'hardwood' floors, - - etc.,etc.

Steve Unkie · 02-18-2006, 11:53 PM

I have never used greenboard as a tile backer,always use concrete board or hardibacker. I don't think 'regular' wallboard meets code as a ceramic tile backer or as a wallcovering for showers, unless it is covered by a shower surround.
I've read reports that said that greenboard that had been stocked outdoors,uncoverd in rainy conditions,were tested with a moisture meter and had not been affected by the moisture. I am skeptical of this report, but I know that regular gypsum would be toast.

I have'nt had the pleasure to use DenShield yet but may have to give it a try sometime.

Steve Unkie.

Tom R · 02-19-2006, 12:08 PM

No argument there, - - do keep in mind, though, - - that your roof sheathing would also be 'toast' if stored (directly) exposed to the elements for some length of time, - - yet it works fine when the finish roof material is installed correctly.

I've torn apart tiled shower walls with 3/8" DRYWALL that were approx 35 years old and were still in DAY ONE condition, - - customers just wanted a 'fresh' look. Granted, - - WORKMANSHIP may have had something to do with it!!

The only way the drywall SHOULD fail, - - if done properly (on the interior), - - is if there is EXTERIOR leakage coming in. And in that case, - - it may actually turn out to be a BENEFIT to have such failure, - - and catch it in time before the said framing ROTS beyond repair.

Let me provide an analogy in another BATHROOM location, - - If you've ever seen a PROFESSIONAL 'caulk' a toilet/floor connection, - - you'll notice he'll caulk only the front and sides, - - not the back.

If he were to caulk the back, also, - - would the seal be more WATERPROOF??, - - YES, DEFINITELY YES, - - but would that be more DESIRABLE??, - - NO, DEFINITELY NO.

That's because in the BIG PICTURE, - - it's actually cheaper to HAVE and CATCH the leak early on!!

Here's a note that may be worth NOTING, - - just last year I got called in to locate the source of a leak on a first floor ceiling/wall intersection of a two story colonial, - - they owned the house just a few years.

Checked around some, - - got up on the roof, - - and couldn't miss that the fact that at some point, a roofer had CAULKED instead of FLASHED a second-story bathroom skylight!!

Apparently, it had been leaking for years, - - running down the roof, - - then down the insides of two shower walls, - - and finally (sometimes) making it's way all the way down to the first floor ceilings.

The bathroom (as far as they knew from the previous owners) had been done about 15 years prior. Nice job, - - CBU and tile.

OK, long (enough already) story short, - - I ended up having to reframe the whole back corner of the house to replace the completely rotted framing members, - - and yes, - - you've got it, - - therefore, completely gut and remodel the whole bathroom, too.

Was the CBU waterproof, - - YES, DEFINITELY YES!!

Did that work to the customer's advantage??, - - NO, DEFINITELY NO!!

Greg Di · 02-19-2006, 08:55 PM

Quote:

Originally Posted by Mike Finley

Hey, elaborate on that. I went from cement board to Hardi backer and thought that was a big improvement!

DenShield is a gypsum-based board, much like conventional drywall, except that side you tile on has a rubber-like coating on it that is impervious to water penetration. It's made by G-P.

It cut's like regular drywall, is lightweight, and requires no vapor barrier on the studs because it's impervious to water. I use Rock-On or Scorpion screws to hang it.

You can also use it on the floor as well.

Trust me...this stuff will change your life.

copusbuilder · 02-20-2006, 04:16 PM

Quote:

Originally Posted by Tom R

In actuality, - - 'old school' guys DON'T use greenboard in wet areas, - - but 'new-school' guys will CONTINUE to say they do until the customers just 'won't buy it anymore'!!

Real 'old-school' guys have always continued to use 'regular' wall-board, - - part of the reason being that they didn't trust the 'new-fangled' product 'claims' of 'greenboard' at the time, - - and guess what, - - they were RIGHT ALL ALONG!!

That's part of the reason, too, why the 'old-school' guys are still somewhat SKEPTICAL, - - 'especially' when their 'tile-on-wallboard' methods have lasted for decades, - - and most often 'right through' the 'short lifetimes' of many of the newer products that have had much more claim than climax!!

Now that saved me a s-load of typing

all these new products that all the saleman cream they're jeans over and they are gone with mountains of problems in not time.

Well said Tom

Mike Finley · 02-20-2006, 07:33 PM

Quote:

Originally Posted by Greg Di

DenShield is a gypsum-based board, much like conventional drywall, except that side you tile on has a rubber-like coating on it that is impervious to water penetration. It's made by G-P.

It cut's like regular drywall, is lightweight, and requires no vapor barrier on the studs because it's impervious to water. I use Rock-On or Scorpion screws to hang it.

You can also use it on the floor as well.

Trust me...this stuff will change your life.

I'm going to have to try it out. I've seen the stuff but never used it yet, thanks Greg.

Greg Di · 02-20-2006, 09:41 PM

Go to the G-P website to read all the info on it. There's a lot more I failed to mention.

player2watch · 01-30-2008, 09:54 PM

desheild is the best tile backer out there. in my opinon. it dose not wicwater where cement board will. as far the ceiling in a shower and green board an stud spacing depends on 1/2 inch or if it 5/8 inch. they have humiteck board the purple board. it would do well for tat celing paint it with a good paint. a rumor for my drywall vendor that they going to stop making greenboad .

bonniem86 · 03-17-2008, 12:52 PM

Client has a basement with a sump pump that's battery backed-up! Recent storm so heavy, battery wore down and water damaged entire basement. They want to redo and I've suggested either dens shield or dens armor ... any suggestions or feedback would be welcomed.

BUTCHERMAN · 03-17-2008, 07:31 PM

Quote:

Originally Posted by bonniem86

Client has a basement with a sump pump that's battery backed-up! Recent storm so heavy, battery wore down and water damaged entire basement. They want to redo and I've suggested either dens shield or dens armor ... any suggestions or feedback would be welcomed.

Definately dens armor. It's unbeatable for mold.

BUTCHERMAN · 03-17-2008, 07:37 PM

Quote:

Originally Posted by Teetorbilt

We're using purple board here, anybody else?

Yes, that's the XP board. It's supose to replace green board because it's mold and mildew resistant. I hear they are going to put green paper on it instead of purple. I think they started already using a somewhat olive green where MR is still bright green. It still don't work like dens armor but it's a good alternative if you don't like the face of the board. Just make sure you're dealing with moisture and not flooding if you use it in a basement.