Discussing tile methods

Greenboard drywall is used in bathrooms, basements, and other areas where the drywall may be subjected to damp conditions, humidity, and the occasional minor splashes of water. Using greenboard drywall in a wet location (shower) is a recipe for disaster. At the very least, severe mold growth will occur, if not outright failure of the product. Won't float here, even if it did, sorry charlie, it wouldn't be wise. Ask any inspector what he really thinks and knows, he/she will tell you. Just my 2 cents worth but, right is right. Years ago, that is all they used, and, a decade or 2 later, wanted to redo the bath, and what they found when it was ripped out, turned your stomach. Talk about unhealthy.

Justadrip said:

Maybe your inspectors don't know any better? Or are they not up to date on things?
What about what SoCal1 posted? That's a lot of good facts supporting the drywall cause.He really seems to know his stuff. ...and he is an inspector.

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When researching online it is easy to get mixed opinions. Glass mat drywall and gypsum drywall are two different products. Gypsum drywall, white, blue, green or purple with a paper face is not approved - I hope that is more clear.

If you want to use gypsum drywall and build a crappy shower by all means but understand that it is not allowed. If your tile men bring you drywall and tell you it's fine tell them "I'm just going to call city hall".

To believe to words of a couple of men without checking and double checking is lazy and will cost you down the road. This is your shower. Building it is hard. If you want easy - hire a pro and specify that all TTMAC or ANSI guidelines be followed. Then you need not worry about getting gypsum in your shower.

If you still think that I have no clue what I'm talking about and believe the mis-information then use drywall, but instead of kerdi use a liquid membrane, use the reinforcement mesh and coat the backside as well making the board waterproof on all sides of the bottom 18". I'm sure it will work. Liquid membranes stick better to plain drywall than thinset. Plain drywall as in no primer, no topping coats, just plain drywall.

If you think this is not a good idea, your right. If you still think that kerdi is OK, call them up. The head of the NTCA recommended to me that Schluter be kept in the loop with any drywall projects. Do that. If the service from your rep is as poor as mine you might get a call back to look at the job in a week or five. But don't trust the words of a "Online poster" over your own city hall or the manufacture themselves. And get a copy of the instructions in writing from Schluter.

Have you ever seen drywall in a shower? I have. But I do demo and build new showers.

drywall in showers - insane.

These code sheets are available online. Look them up. Or trust a random poster with 4 posts that claims to be an inspector. I mean no dis-respect but if you are in fact an inspector SoCal1 then please share your office phone number so anyone reading your words can double check.

604-990-2480 Here is the phone number for the permit enquiry in North Vancouver. Just ask for a building inspector and check your self.

This is not new information. It's all easy to find. You just need to place a little effort into checking your facts. To build a bathroom and invest $4,000 - $80,000 into it an spend less time looking into the facts than you did picking and test driving your last car is crazy. This is your home. You want it right.

If you want cheap - then go cheap. Bang on some poly and board it with cement board! That's cheap. That's also code approved. Fact.

JW

And, John, you still can't get it through your head that when behind a totally waterproof membrane applied system (and system is key here - they call it the Schluter Kerdi shower system for a reason, impling a TOTAL design, not patchwork), the drywall is NOT in the shower, just like it isn't in a wet area next to the windows, or on the ceiling under the roof.

Nobody is saying using drywall IN a shower is a good idea when just tiled or with a system that has not been tested and approved, but with a properly installed, tested, and approved material like Kerdi, it is perfectly fine. If the manufactuer has independent test results proving it is a viable method, the TCNA defines the procedure as an acceptable method, and the governing agencies approve it, practical experience for decades has proven it...local exceptions aside, it is a viable method to build a shower. That you prefer other materials or methods is not a problem with me...your direct disregard for the nationally approved testing agencies against a proven method is approaching slander.

For example, here's the Massachusetts state plumbing approval listing for Schluter Kerdi http://license.reg.state.ma.us/pubL...er&model=&product=&description=kerdi&psize=50

For you to say it is not approved, is just ignorant and wrong. There are similar approvals for most places, if you care to dig them up, local exceptions aside. The Schluter Kerdi Shower system works as advertised, and as advertised, lists drywall as an acceptable membrane backer material. For you to say otherwise, is just plain wrong.

jadnashua said:

And, John, you still can't get it through your head that when behind a totally waterproof membrane applied system (and system is key here - they call it the Schluter Kerdi shower system for a reason, impling a TOTAL design, not patchwork), the drywall is NOT in the shower, just like it isn't in a wet area next to the windows, or on the ceiling under the roof.

Nobody is saying using drywall IN a shower is a good idea when just tiled or with a system that has not been tested and approved, but with a properly installed, tested, and approved material like Kerdi, it is perfectly fine. If the manufactuer has independent test results proving it is a viable method, the TCNA defines the procedure as an acceptable method, and the governing agencies approve it, practical experience for decades has proven it...local exceptions aside, it is a viable method to build a shower. That you prefer other materials or methods is not a problem with me...your direct disregard for the nationally approved testing agencies against a proven method is approaching slander.

For example, here's the Massachusetts state plumbing approval listing for Schluter Kerdi http://license.reg.state.ma.us/pubL...er&model=&product=&description=kerdi&psize=50

For you to say it is not approved, is just ignorant and wrong. There are similar approvals for most places, if you care to dig them up, local exceptions aside. The Schluter Kerdi Shower system works as advertised, and as advertised, lists drywall as an acceptable membrane backer material. For you to say otherwise, is just plain wrong.

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The approval you posted a link to is not the "system" as a whole but individual parts of Schluter. basically what I'm telling you is just because the product is listed doesn't mean your paperboard backer is even tho Schluter doesn't have a problem with it.

Slander is spoken...libel is written.

Just like the "pex connected to an electric water heater" debate. Some of the manufacturers say its perfectly fine......and what do some of you guys say in response to that???? Code says NO. The PEX is listed and approved just like the Schluter but that doesn't mean the code doesn't place restrictions on it.

Hackney plumbing said:

The approval you posted a link to is not the "system" as a whole but individual parts of Schluter. basically what I'm telling you is just because the product is listed doesn't mean your paperboard backer is even tho Schluter doesn't have a problem with it.

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The point is, all of the required parts of the SYSTEM are approved for use, and if you ask any of the inspectors, they will tell you to install it per the manufactuers instructions, similar to when you install a WH, furnace, boiler, etc...must be installed per the manufactuer's instructions. When done according to them, this SYSTEM, along with many other methods produces a viable, long-term reliable shower. Choose your favorite for your circumstances and preferences...doesn't make one invalid just because you like something else better.

jadnashua said:

The point is, all of the required parts of the SYSTEM are approved for use, and if you ask any of the inspectors, they will tell you to install it per the manufactuers instructions, similar to when you install a WH, furnace, boiler, etc...must be installed per the manufactuer's instructions. When done according to them, this SYSTEM, along with many other methods produces a viable, long-term reliable shower. Choose your favorite for your circumstances and preferences...doesn't make one invalid just because you like something else better.

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All the parts of a PEX water system can be approved and the manufacturer can say it is OK with them if you install PEX directly to the electric heater but the plumbing code can refuse it. The ole 18" rule.

You remember this one well....it's time to have the situation reversed on you. Just like I said in this thread earlier......people (including inspectors) like to play the code to say what THEY want it to say. Kinda like the Bible.

Not to be disrespectful, but all systems are capable of failing, with the exception of cement board, I never heard of cement board failing when exposed to water. For whatever, reason, if the Kerdi system fails from a water souce outside the bathroom, you got a big problem if you got drywall or a MR board that the water can attack.

From a DIY perspective....

It takes the same amount of labor for said products.
Well, maybe a lil bit more on lugging the CBU. And a smigen more effort when cutting it if not making RO cuts.
Just a lil more messy as well....
So why pitch drywall, in any given scenario.
That stuff get's soft real quick....

chefwong said:

...So why pitch drywall, in any given scenario.
That stuff get's soft real quick....

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Thank You.

JW

Yes it does, doesn't it?

chefwong said:

From a DIY perspective....

It takes the same amount of labor for said products.
Well, maybe a lil bit more on lugging the CBU. And a smigen more effort when cutting it if not making RO cuts.
Just a lil more messy as well....
So why pitch drywall, in any given scenario.
That stuff get's soft real quick....

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Working with cement board can be messy.

It does weigh more.

It's tuff to join two sheets over one wall stud. Bad approach anyway.

And they are weak between sheets if not taped with thin-set like the supplier suggest. The minimum code is 2" drywall tape and thin-set. You know what's better?

Cover it with Kerdi - if that is your membrane of choice. Now you have a proper backer board and a shower build above building codes - not below.

This same membrane used over drywall nets a shower built below building codes, or for argument sake one built around loop holes and meetings.

JW