Latest Discussions : Miscellaneous


07:05AM | 02/16/05
Member Since: 02/15/05
2 lifetime posts
I hired a contractor to remodel an original bathroom in my 30yr old house. It was old and yellow the shower/tub was leaking into the kitchen below it. We wanted it gutted to the studs.

We paid a third down a third at rip out and the final payment was to be paid at completion. The contractor had numerous delays. They ordered the wrong tile. They recommended a bath tub that required custom shower doors. They did not always show up when the were supposed to. The fixtures and material were never at ny house when they were supposed to be there. The contractor does not return phone calls in a timely fashion.

When the shower/tub was finally completed and I turned on the shower water poured into the kitchen below. It turns our that the contractor did not use a licensed plumber to do the work. The pipes wre not soldered or insulated (this is an exterior wall). The contractor brought back a licensed plumber who had to rip out the tile in the shower. It turns out that the walls were not taped or spackeled. the ceramic tile was just put up right on the drywall. In addition on of the walls in the bathroom is now bowed and the medicine cabinet is not fully attached. The bathroom door is also damaged. The contractor insists that he will make good on everything. Obviously I do not trust him to do any more work in my home. How do I get rid of this guy without paying any more money. I also now have concerns about the floor. I believe that they tiled right onto the ply wood.


05:30PM | 02/20/05
Member Since: 11/06/02
1278 lifetime posts
In many states, you are required to provide a contractor sufficient time to make good on his work.

But that depends on whether he is a bonafide contractor with license and permit. If he has not toed the line from a legal standpoint, he is plumb out of luck. In most places you could lock him out and never have to deal with him again.. But it does all depend on the legality of the whole arrangement in your state.

From yopur account, it does not sound like this hack had the faintest idea how to do the work professionally. That suggests to me that he is unlicensed and acting outside the bounds of the law.

Not only is his professionalism lacking, but his trade skills are deficient as well. tile in a shower should not be applied over drywall. The way to keep it from leaking below is to line the studs with a water barrier, lapped and sealed to the lip of the tub, then to install cement baord on top of that, tape it, and then install the tiles.

Grout is not waterproof, so it is only a matter of time before the drywall base disolves from behind the tils, and without tarpaper or better barrier backing it up, that water will leak through.

As for his failure to use a licensed plumber...I have lived and worked in several places where licenses and permits are not required for small jobs such as this, but a licensed plumber has always been required, as far as I know. This was just plain foolish.

As much as I feel for you, I would like to point out to others who may be reading this, that selecting a contractor involves a degree of work on the part of the homeowner. One should always seek recommendations from friends and neighbors who have had similar work doen, ior followup contacts wioth previous customers of the contractor you may be considering. Trade associations can be a point of contact as well. Your story makes it sound as though this "contractor" has never done this sort of work before or as though chemical abuse may have interfered with his judgement and progress.

Excellence is its own reward!


06:55PM | 04/03/06
Member Since: 04/02/06
5 lifetime posts
Due to past experience with shoddy contractors, I requested a master plumber for my bathroom work from one of the major plumbing outfits (not RotoRooter).

I now have a 4' hole in the kitchen ceiling -- my new tub rained on the kitchen below also.

He did not tighten the waste pipe.

It seems no matter how I try to protect myself from past experiences, new ones arise. While things can't be expected to go perfectly along the way, there seems no end to the carelessness out there these days.

I don't know how you get around it.


06:19PM | 11/22/06
Member Since: 09/24/06
50 lifetime posts
According to this link and other information I have gathered, it is ok to install ceramic tile on top of drywall, as long as you use greenboard, or fiber-rock or other water and mildew resistant material instead of plain drywall.

You'll be running a bead of silicone around the tub and fixtures anyways, and putting 2 layers of grout sealer on.

No solder on the pipes????? did they get the sections to stay together without solder??? Even I know this.

You do need drywall tape and "mud" though on that greenboard, however.

I would just tell your contractor to fix all the problems and complete the contract correctly as established. You paid him to remodel the bathroom WITHOUT any leaks. If there are leaks, it's HIS responsibility to fix them. You shouldn't have to pay him extra for this.

Hmmm...You could in the future consider doing this work yourself. I just redid my shower enclosure, fixtures, and plumbing, with no prior experience. It's not that hard to solder a pipe, or put up drywall correctly.


03:27AM | 11/24/06
Member Since: 11/06/02
1278 lifetime posts
It's nice that you can find links that tell you what you want to hear nowadays, but it just ain't always true.

Thirty years ago, it was considered acceptable to install tile over greenboard in wet or damp locations.

but experience has taught us that this will always fail - whether in three years or twenty depends on how much water it is exposed to. Green board is water resistant, not water proof.

Tile sealers are also water resistant and not water proof.

So anyone who doesn't mind taking a chance can go ahead and install over greenboard, but those of us who do appreciate quality and eschew moldy homes use professional installation methods to avoid that.

Excellence is its own reward!


03:51PM | 11/29/06
Member Since: 09/24/06
50 lifetime posts
Well, I apologize...maybe not greenboard. I haven't done that much research on greenboard.

I do know, however, that unless you put up plexiglas or plastic walls, then NOTHING is waterproof, not even cement board. And I don't know that many people who put up plastic panels on their studs.

And you're right...EVERYTHING fails eventually. Whether it's greenboard, cement board, fiberock, or whatever. So that point is irrelevent.

Have you ever seen cracked concrete driveways? Do you know what causes this? Yep, moisture absorption. Concrete and cement are porous.

THIS is fiberock...and the installation instructions clearly state that you can install tiles using adhesive directly on top of the board.

It should be perfectly adequate for most applications.


02:54AM | 11/30/06
Member Since: 11/06/02
1278 lifetime posts
Apparantly you did not read my statements carefully enough. There is a way to make such installs waterproof. you line the studs behind the cement backer with tarpapr or other membrane that laps over the tub lip, following same principles as in any other waterproofing endeavor. It is not hard or expensive.

Taking the attitude that it cannot be done so it shouldn't be attempted to justify using a failing thirty year old process is not beneficial. The industry has moved beyuond that. Time for you to catch up.

Excellence is its own reward!


08:48AM | 11/30/06
Member Since: 09/24/06
50 lifetime posts
So what's to say that you're not just "a link telling me what I DON'T want to hear"? As you say, any information on the internet is potentially doubtful. Even this forum.

But anyways, now you're changing the subject.

I NEVER said that cement board was not superior to greenboard or regular drywall.

My point is that cement board too will fail under moisture eventually, and that fiberock or greenboard should be sufficient for MOST home shower applications.

The original poster was mentioning that their contractor placed tiles directly on top of the drywall. I am saying there's nothing wrong with this, as long as you have water resistant material.

And yes, according to your methods, the STUDS will be waterproofed, but how does this help the backer board?

The BACKERBOARD , and not the tarpaper, is directly underneath the tile.

I don't see how waterproofing the studs will help stop moisture from getting into the backerboard.

It's not a difficult concept to understand.

The moisture, as you say, penetrates the sealer, the tiles, the adhesive, and the grout, and can get to the backerboard, whatever material it may be.

I can find enough information to prove that fiberock, or even water resistant drywall, can withstand normal shower use, although you probably wouldn't believe me anyways. I honestly don't believe that 99% of the staff at both local building stores I went to would recommend the wrong product, and that the manufacturer would lie and put a 20 year warranty on their product if it was going to fail in 3 years.

That is, Mr. Piffin, unless you prefer saunas or use a pressure washer when you shower...


10:24AM | 11/30/06
Member Since: 11/18/98
187 lifetime posts
This does not have to do with the tile failing. It has to do with mold or rot deep in the walls.

Watch this video you will notice the pros already have the tar paper behind the backerboard.

This is not to protect the tile or backerboard from failure as a small amount of moisture may eventually make it through even cement. What this layer is doing is protecting the studs , the insulation and whatever else may be inside the wall.

Is it code? Is it neccessary?

Maybe not.

Is it an easy layer to do that is cheap and will provide peace of mind? yes.

doug seibert

06:35PM | 11/30/06
Member Since: 08/10/02
842 lifetime posts



07:01PM | 11/30/06
Member Since: 04/25/05
1915 lifetime posts
"I honestly don't believe that 99% of the staff at both local building stores I went to would recommend the wrong product, "

If you are talking about places like HD and Lowes they are famous for many of the employees not knowing what they are talking about.

"My point is that cement board too will fail under moisture eventually,"

No, you can soak an of the CBU's in water forever and it won't fail.

It is completely water resistant. But it is not waterproof. That is it will allow moisture through.

That is why you want to install a barrier behind it to product studs and insulation behind it.

There are also different trowel on, paint on, and films that can be applied over the backerboards (of any kind) to water proof the assembly.


02:53AM | 12/01/06
Member Since: 11/06/02
1278 lifetime posts

The link here contains photos showing exactly what I have seen four times where tile was applied over greenboard in a shower application. I was the one called to rebuild things. I have also seen the same with plain drywall.

I am a professional remodelor with 35 years of experience. There was a time when I installed tile over greenboard, but I learned better - a long time ago. I am trying to help others profit from my experience. If you want to continue to insist that greenboard is acceptable, be my guest, but that does not make it so.

Another point to clarify is you advice above that the joints should be taped and caoted with "mud" before tiling. Ordinary premixed drywall joint compound will disolve on its first exposure to water. It is important to use a mixed setting type compound such as Durabond which sets through a chemical reaction with the water in the mix rather than by dying in order to have a permanent water resistant "mud"

I am not pointing all this out so much to argue with you as to make sure others reading here have the correct information when they attempt to DIY their bathrooms.

'nuff said

Excellence is its own reward!


07:55AM | 12/01/06
Member Since: 01/28/03
693 lifetime posts
Actually greenboard CAN still be used in tub and shower compartments as a tile backer.

'Best Practice' notwithstanding, wherever the 2003 International Residential Code is in force, it is 100% permissable and Code compliant to use moisture resistant gypsum board as a backer for tile PROVIDED no vapor retarder is used under the backer and all edges are sealed according to the manufacturer, and the material complies with either ASTM C1178 or ASTM 630.

Section R702.4.2 (2003 IRC) GYPSUM BACKER: "Water-resistant gypsum board shall not be installed over a vapor barrier in a tub or shower compartment. All cut or exposed edges, including those at wall intersections, shall be sealed as recommended by the manufacturer."

The reason no vapor barrier can be used behind greenboard is because while greenboard is only "moisture-resistant" and not "waterproof", as already mentioned, and although it CAN withstand occaisional wetting and even saturation...Moisture resistant drywall cannot withstand CHRONIC wetting and can breakdown under such conditions.

Using a vapor retarder such as black paper, or plastic sheathing or other material under greenboard in a shoer compartment can create a "Double Vapor Barrier" which can chronically trap moisture within the drywall sheet. This will contribute to its failure because once internally wetted, moisture cannot escape from within the board because of the double vapor barrier on either side and be allowed to dry.

Eliminating a vapor retarder from behind greenboard can eliminate or reduce damage from leaked or condensed water.

Now, that is NOT to say that one SHOULD use greenboard.

I wouldn't do it and do not recommend the practice.

Concrete backer products are indeed superior for the application.

But it remains completely permissible and Code compliant to use "greenboard" whenever and whereever the 2003 version of the IRC is still or will continue being used.

That said, the 2006 International Residential Code has DISALLOWED the use of tradtional 'greenboard' but still allows other types of gypsum products as tile backers in showers:

R702.4.2 (2006 IRC) CEMENT,FIBER-CEMENT, AND GLASS MAT GYPSUM BACKERS. "Cement, fiber-cement or glass-mat GYPSUM backers in compliance with

ASTM C 1288, C 1325, or C 1178 and installed in accordance with manufacturer's recommendations shall be used as backers for wall tile in tub and shower areas and wall panels in shower areas."

So gypsum products are STILL allowed by Code as tile backers, but they must be 'glass-mat' types conforming to the ASTM standards.

Personally as a builder, I'm in 100% agreement with everyone else that one shouldn't EVER use any gypsum product as a tile backer in a shower, but personal preference aside and as a Code Official, it remains legal in most places in the US to either still use 'greenboard' or 'glass-mat' drywall for that purpose, and I would have to approve the use of greenboard or glass-mat gypsum if any builder or homeowner chose that method of construction.


01:32PM | 12/01/06
Member Since: 09/24/06
50 lifetime posts
Yes, I took those pictures of the shower in my new house when I moved in.

It's only fair to include the "After" pictures, however.

Funny thing was...the tile and drywall everywhere else was fine, but around the taps it was rotten.

The previous owner didn't use greenboard though...just plain drywall.

I redid my bathroom walls with Fiberock before I tiled.

Well, anyways, looks like I'm outnumbered. Greenboard is out. What about the Fiberock that I linked to?

All the specs on the MFR webpg indicate that you can use it in bathroom showers, and there are even instructions on how to put it up in a shower.

I don't want to argue either...I just want to learn. And I would like to think that I did my research fairly thoroughly before I put up the Fiberock.
50 you found my picture


01:33PM | 12/01/06
Member Since: 09/24/06
50 lifetime posts
After Fiberock and tile
51 after picture


03:29AM | 12/02/06
Member Since: 01/28/03
693 lifetime posts
Both USG's "Fiberock" and GP's "Dens-Armour" are approved for use in shower compartments and wet locations.

Both are approved by the American Society for Testing & Materials and the International Codes Council.

Various Fiberock products can even be used as structural wall sheathing, underlayment or interior sheathing in wet locations. Fiberock utilizes a combination of gypsum and recycled cellulose.

Dens-Armour/Dens-shield uses 'glass-mat' technology to reinforce the fiberglass sheets which remain mold resistant because unlike conventional drywall, both are 'paperless'.


08:01PM | 01/30/15
Hello, We are renovating our master bathroom and installing porcelain tiles on the shower walls. My contractor is going this route: 1) Studs 2) Greenboard 3) Kerdi (from Schluter) 4) Tile adhesive 5) Tiles 6) Epoxy grout. Is this the correct way to go, in your expert opinion? Thanks a lot.

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