Kerdi board

[johnfrwhipple]

I wonder why the TTMAC specifies cement board in steam shower builds? Perhaps they feel that backer boards should not dissolve with heat and steam. In the TTMAC Specification Guiodelines there is only one backer board listed - It's Cement Board.

If you want Kerdi Board then make it. Use cement board and then cover it with Kerdi. You want a better board. Use cement board and cover it with Kerdi DS!




JW

[LLigetfa]

Here is an alarming topic on the John Bridge forum...

The pictures sure look odd. It looks like there is some sort of paper product and I'm seeing what looks like drywall compound. Do you think there was Kerdi Board there?

[johnfrwhipple]

The pictures sure look odd. It looks like there is some sort of paper product and I'm seeing what looks like drywall compound. Do you think there was Kerdi Board there?

Kerdi Board contains no Kerdi. It is a Kerdi looking fabric, Special reinforcing layer (looks like mdf), foam, Reinforcing layer and then Kerdi looking fabric. I believe the waterproofing comes from the glue that holds the fabric to the reinforcing layer. Kerdi Board is weakened once this MDF or reinforcing layer gets wet.

Sounds like they pinned a steam line to a slab wall and then Kerdi Boarded over top.



This is a pretty typical steam shower install. Look at the fact that the steam line's insulation is in contact with the Green EBoard backer board. Some steel stud work on our current project. We wrapped the steam line with high heat insulation.





Look how close the steam line is to the back side of my Green EBoard. Green EBoard is fire rated. Green EBoard will not melt from heat. Green EBoard is also water resistant and I find Kerdi Board to be water absorbant.


Of course this picture does not show the drywall or Kerdi Board wrapped on all sides but it does show you how far water will wick once a penetration is there. I bet that the heat from the steam shower produced condensation on the back side of the Kerdi Board and then it started to weaken and then fail. I would imagine that some high heat insulation might have prevented that failure. I also bet that a cement board and kerdi install would still be going strong.

JW

[johnfrwhipple]

Tested the MDF layer with the orange fabric set with Kerdi Fix. This is waterproof, if you like using paper based products in your waterproofing systems...

JW

[dlarrivee]

For anyone trying to keep up, John (W), doesn't like Kerdi.

He likes some random backerboard (friends with owner/distributor?) called Greeney Board, he like Hilti, and he hates Jim.

[Hackney plumbing]

for anyone trying to keep up, john (w), doesn't like kerdi.

He likes some random backerboard (friends with owner/distributor?) called greeney board, he like hilti, and he hates jim.

lol lol lol

[johnfrwhipple]

I promote all the products that I enjoy working with. I'm one shower builder in Canada. There are hundreds of promoters of your beloved Kerdi - you can follow the other sheep that flock with the JB crew. I choose to stand alone with my own techniques and build better showers. Call me a hater.

Have you shared any useful information Dlarrivee? Or do you just like to rag on people?

JW

[Hackney plumbing]

I laughed at what he postsed but i still agree with you Whipple.

[johnfrwhipple]

I laughed at what he postsed but i still agree with you Whipple.

Thanks. In the end we all get better with these debates. We all win or we all at least get to make a more educated choices.

The internet should be about free flowing information. This information should not be placed online as yet another marketing tactic but as real world expeirence. Sadly I find most information is posted by people with no ______ clue.

JW

[dlarrivee]

John I don't build showers for a living, you do, why would I argue with you?

I poke fun to lighten the mood, this isn't a court house.

[johnfrwhipple]

John I don't build showers for a living, you do, why would I argue with you?

I poke fun to lighten the mood, this isn't a court house.

Thanks for the clarification. I get so many haters following me around it is hard to tell those that are "Chirping Me" from those who are just having fun.

Have you read threw the link today? So funny. What a cluster ____ of answers and opinions.

"The paper is water proof"

"No the foam is"

"The old stock was wrong and it's fixed now."

"No it might be the new stuff."


How do you tell which Kerdi Board is the old from the new? Jim any ideas? Seems like some of the original stock is still out there and it sounds like (if you read between the lines) maybe some of the newer German made stock is also delaminating.

No wonder Schluter is helping out on this failed steamer. I would want to know if it was my install or the product itself that failed. Looking at the paper layer of Kerdi Board peeling right off makes you wonder how strong a board this really is.

The best way to make Kerdi Board is with "Board" and "Kerdi" two things Kerdi Board does not have. Unless you count foam and paper as board.

Use cement board and then apply Kerdi. Done. You can't carry ten sheets at a time but you don't need to worry about your job just fallening off the wall...

JW

Jim how do you tell which Kerdi Board is from which plant and when it was made?

[jadnashua]

I've not used nor touched KerdiBoard, so have no input, one way or the other. But, if you read the installation instructions, all seams and joints or penetrations are required to be waterproofed, either by the standard minimum 2" overlap with fabric (band or sheet material) and the penetrations with the gaskets or KerdiFix. Done this way, no water should penetrate, and thus, the problem should go away. Working with any of these materials, good workmanship is the key to success - any system can fail if you do not follow all of the instructions.

[johnfrwhipple]

I've not used nor touched KerdiBoard, so have no input, one way or the other. But, if you read the installation instructions, all seams and joints or penetrations are required to be waterproofed, either by the standard minimum 2" overlap with fabric (band or sheet material) and the penetrations with the gaskets or KerdiFix. Done this way, no water should penetrate, and thus, the problem should go away. Working with any of these materials, good workmanship is the key to success - any system can fail if you do not follow all of the instructions.

I called Schluter tech support today and spoke with Paul. He could not tell me the proper method over the phone. He mentioned something about issues and that I need to speak to Dale Kempster.

Odd don't you think that a Schluter tech support person does not know how to finish the detail around a steam line. Kerdi Board is sold as a steam shower backer board - if I'm not mistaken.

Jim how do we know what Kerdi Board is made where? How do we know what is the old 2008 stock and what is new? If the new run is better than the old production run, how do we know we are not buying the old stock?

Can you ask your buddies how we check the manufacture's date.

Rod has been having issues and I hear the original board as well is suspect. John Bridge has commented online that this issue is sorted out now, but how do you know which stock is which? I believe that 1/2" Kerdi Board is made in the USA and all other stock gets shipped from Europe.

Jim how do you seal Kerdi Board to a steam shower line? What is the specification?

I called weeks back and was told I could even use regular drywall in a steam shower by other Canadian Schluter tech support girl. Your a big fan of drywall in showers Jim, so how would you seal around a steam shower's 5/8" brass line with drywall and Kerdi? Should be the same spec with Kerdi Board - right?

JW

[jadnashua]

The tech sheet says ALL penetrations need either one of their seals, or KerdiFix to ensure there is no chance of moisture getting inside of the board. Normal joints/seams require the same thing as Kerdi sheet membrane - a minimum of 2" overlap of material with an unmodified thinset bonding. The inside of the shower/steam room, when using KerdiBoard must be made waterproof and penetrations properly sealed to prevent moisture or vapor from intruding into the system. As I said, I have neither touched nor seen KerdiBoard, and other than the tech sheets, I don't know any more about it.

For others that may read this, the shower in question is a commercial steam room, likely run many hours a day. From what I read, Schluter is on site trying to help understand what went wrong and how to fix it as any of the quality companies out there typically do when there's an issue if you contact them.

Let's not come to a conclusion until more is known.

A typical home steam shower is used probably less than an hour a day, if that, giving the whole thing a chance to dry out if vapor did get places you'd rather not get it. Schluter does not approve of gypsum based backers for commercial steam showers (per their Kerdi shower handbook installation instructions) that are likely to be used much more than that. No membrane is 100% given high steam concentrations, and an inert backer is required when it is likely it will have minimal chance to dry after long-term, continuous high vapor pressure exposures of a commercial operation. For a home, a typical steam shower use probably isn't worse than a typical teenager's long, use all the hot water shower, and for those applications, accepts the use of numerous backer materials since there's typically a large percentage of the day when it is unused and drying.

One thing to consider, steam can get VERY hot, just like any gas. While there's a limit on how hot liquid water can get unless under pressure, there's no such limitation once it becomes a gas. There's no way to know what temp the steam was in that system that could have been run 24/7, and the steam line ran, uninsulated for the most part, right behind the board. A typical home steam shower, the pipe comes straight into the shower, and doesn't run long distances against the backer , entering at a 90-degree angle with minimal contact with the backer, keeping the run short to maximize the effect and efficiency of the system. A commercial system could be feeding multiple shower rooms, and would likely run hotter and would need to be piped further.

[johnfrwhipple]

Jim KerdiBoard only has a 158F degree rating to it. I see your commenting that at 212F degrees Kerdi Board should be OK. Where did you pull that fact out of? Did they tell you that at the Schluter training? I thought you said you never even touch it. Now your posting that at 212 it should be OK when it is only rated at 158???

Schluter tech said the steam lines come in at 110F.

Where do you find these facts?

JW