Kerdi board

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kcchiu

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Greeting,

Does anyone know where to buy Kerdi Board ?

Thank you
KC
 

Jadnashua

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This is relatively new product (the preapplied Kerdi, not the membrane itself). The best thing would be to call Schluter directly and ask.
 

Jadnashua

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I had heard of the stuff (I've used Kerdi before, but the Kerdiboard is new) and did some investigation. It's a structural extruded foam panel with Kerdi applied on both sides (well, it is not exactly like the sheet goods - fleece, reinforced waterproof sheet, foam, with the same on the other side; Kerdi has fleece on both sides of the sheet). One side has a grid on it at 3/8" squares to help you cut it in a straight line. It comes in sheets in various thicknesses from 3/16" up to 2" thick and in various widths and lengths up to 96" long. You can use it in place of CBU on the walls, or as in structural panels for things like a vanity, tub deck, shower seat, etc. that you will be tiling. They also have preformed corner boxes and U-shaped ones for things like pipe covers or chases. There's even a sheet that is designed to bend to make curves. The 2" stuff is sturdy enough to make a tub deck out of and they have various trim pieces for the edges in SS if you want, or other finishes , or you can tile it. Neat stuff. You can cut it with a sharp utility knife (although the 2" stuff might be tougher!). Check out www.schluter.com for more info.
 

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JohnfrWhipple

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Q: How do I anchor the Kerdi Board to the mud wall?

Found this answer online today. Talk about an epic fail of a response...

"Thinset, kerdi fix, sikaflex or (my personal choice) PL Premium. Make goobers every 8 inches or closer on center and, using a 4 foot level as a straight edge and level, press the board into the goobers making the board perfectly plumb and flat.

Then kerdi band the seams, and caulk (sikaflex, kerdi fix) to the tub itself." - Source


Why is this an epic fail of an answer? So many reasons. For one PL Premium expands while it cures. For two the poster offered up not way of stopping this. And for three if you saw the original post in the discussion the wall currently looks like this.

attachment.php

My Thoughts on This:

The fellow who offered up this advice is one of the forums busiest posters. Another huge promoter online of everything Kerdi.


What an Epic Fail of advice. Before following this train wreck email Schluter and ask if that is the right way : info@schluter.com

There is the email address above. If you want Schluter's head technical rep email Dale at DKempster@schluter.com


Had I written this advice online here on Terry's forum our local Kerdi salesman would have attack me for not following manufactures protocol. Our local expert likes to sign the praises of following every printed rule. makes me wonder why he does not do the same on the other forum. So Sad. So Odd.

Dots of PL expanding. Flexing backer board. poor substrate to bond too. And not one tile pro speaking up to say that the advice hailing from Houston was an epic fail....

A better approach:

A smarter approach would be to drop the old mud wall. Inspect for damage and bugs. Repair and replace missing insulation. Bring vapour proofing systems up to local code.

Then re board. Kerdi Board is one of the worst shower building products I have tested and used. So flimsily. A better approach to the kerdi system would be cement backer board then Kerdi.

A better system all together would see the use of a less restrictive waterproofing system all together. Noble Company, Laticrete, Mapei, Custom all make alternatives to kerdi that are less restrictive in thin-set selection.

 
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JohnfrWhipple

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Kerdi Board - Practical Uses

attachment.php


Here is a practical use for Kerdi Board. Not used as a backer board. Not used as a water proofing system, but rather as scrap material to prevent a self levelling pour from hitting the water supply lines.

I will never tile over Kerdi Board, nor would I trust it on a shower build of mine.
 
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JohnfrWhipple

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Another good use for Kerdi

---.jpg


Not sure how they add the edges but this could be awesome to prevent the dreaded Blow Out! lol :)

Who takes the time to make these images. And what person goes - yeah, I want that in my shower because it's good for diapers.....
 
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Jadnashua

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It appears the the recommended joint has you using Kerdi-band on the seam. If the goal is to avoid that, then Kerdi-fix should work. My guess is that when cutting, you may debond the edge slightly, and getting a good Kerdi-fix joint may not be as easy as you might think. If using Kerdi-band, I can't see it ever being a problem. Now, adding the Kerdi-fix to an unsupported joint would structurally improve the joint by bonding the two sheet edges together better rather than just gluing on (via the thinset) a band at the top layer where flex at the joint might debond the Kerdi sheet from the foam core. This normally wouldn't be a problem once the tile was up, unless the grout joint happened to align with the board seam.

The cut-sheet with installation and other info for Kerdi-board is linked here: http://www.schluterkerdiboard.com/media/KERDI-BOARD-Cutsheet.pdf

The only time they call for Kerdi-Fix is when the joining point or edge won't accept thinset to make a seal (such as to a tub edge or say a windowsill). Otherwise, you butt the edges together, then cover with Kerdi-band, as you would for using the membrane. As long as you get at least a 2" overlap of the Kerdi materials, the seam will be waterproof. WHen using the panels on studs, say in a shower wall, you need to waterproof the fasteners - Kerdi-band is the recommended method. You need fasteners into studs at a maximum of 12" intervals and either 1/2" panels on 16-studwalls, or 3/4" on larger (up to 24") studwalls. Pipe penetrations could either be made with their special Kerdi pieces, or Kerdi-fix. The pre-made corners could be used there, or you can make your own, as you used to do before they made the corners.
 
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JohnfrWhipple

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Kerdi Board - Poor Installation Video

From one of TV's top Home Guru's a lesson on installing Kerdi Board.

What you can not see is how poorly the Kerdi Board was installed.

From improper framing.

Missing Fastners.

No Kerdi Board to tub seal.

This is a TV version of fast construction.

A joke of a video and more a three minute sales add. My favourite was that Scott's guy installed the first piece backwards and then raved about the grid lines.... Train Wreck.

 
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JohnfrWhipple

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Another insane Kerdi Board Question

Kerdi board over Marble - Source
I met a client today with a Polished Marble shower that is fine shape, plumb and soid (floated), except that the floor is leaking due to cracked a joint at the curb letting the mud base get soaked along with the house cleaning lady recently etching the sh*t out of the wall with a bleach cleaner. I am planing on leaving the walls intact because it's upstairs in a highrise condo and we need to keep the sound and mess to a minimum, then remove the shower floor, refloating it with a new Schluter drain kit with Kerdi over the floor, a new Kerdi curb then install Kerdi board 3/16" on the walls and then set Porcelain on the walls and floor. If any of you guys have over laid Marble or high gloss tile with Kerdi board did you set it with Kerdi fix or thinset.

Thanks



This is so bad. The fellow wants to know if he can thin-set Kerdi Board to Marble Wall Tile. In his post he mentions that the shower floor will be replaced but because of noise he will leave the walls in tact. Then install the Kerdi Board 3/16" over the new floors.

This is where someone has a few ideas. Has blended them together and is hoping someone tells him it's OK to do.

What he is planning is a poor idea. Very poor.

Lets say that the base is redone. Why not tie that into the walls? I'm pretty sure Marble Tile is not listed as an approved substrate for Kerdi Board.

I like Kerdi Board. For things like templates. Crafts. I like kneeling on it because it's soft. Would I use it to build shower walls..... Not in this lifetime.
 
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Jadnashua

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I thought I remembered the instruction manual saying 1/2" minimum panels on a bare studwall. The thinner sheets are designed as a skin for existing flat panels. If the seams are covered with Kerdi material or Kerdifix, the fact that the foam absorbs water is immaterial, since none should ever get there. Same idea as their preformed pan or curb...cover it properly with Kerdi, and it's stable and waterproof. I'm surprised they didn't call you back. Maybe they tried, but no one was home at the time.
 

Dlarrivee

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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.
 

Dlarrivee

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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.
 

Jadnashua

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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.
 

Jadnashua

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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.
 

Jadnashua

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The steam line should be insulated. It should not be in direct contact with the material. This is for two reasons: to keep the line hot possibly making the surface dangerously hot to occupants, and to preserve the material. A steam line run in direct contact with any surface that is tiled could put some really bad stresses on the ceramic or stone tile on the surface - especially in a commercial steam room that may run extended hours. It could get hot enough to burn someone and be a safety hazard as well.

Steam is the vapor created by boiling water. Water boils at 212 at sea level. Steam CAN be significantly hotter. Since it originated from boiling water, which was 212, on the outlet to only be 110, most of it would have condensed, and you won't have much steam...saturated air, certainly, but not steam. So, you could have lots of heated mist at 110, but not steam. The mist is liquid droplets of water, steam is a colorless vapor. The mist forms when the steam hits the cooler air of the steam room. So, how does a steam generator making at least 212-degree steam vapor at the source, ensure it is only 110 at the outlet?

The foam won't melt at 212, but the rest of the structure might have problems. I did find in the spec sheet a maximum of 158-degrees F - missed that the first time through.

No idea how hot the actual steam pipe got, but it wouldn't surprise me if it exceeded that if ran uninsulated against the back. Depending on where the steam generator is located, it's likely to exceed that for at least some of the run, if not all.
 
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Hackney plumbing

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Everyone that has common sense knows that a paper based products are inferior to a cement product. Mr.Whipple........it is very difficult to defeat "stupid".....I have defeated it in the past but it takes many posts......as your finding out.
 

Jadnashua

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Since I've never seen Kerdiboard except in pictures, I don't know if it has a code stamped on it like some food products, or other items for batch control. If it does have a printed number on it, the manufacturer would probably know how to decode it.
 
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