# Kerdi Bath



## redwood (Dec 5, 2007)

I think that I know the answer, but I'll ask anyways.

I have a good client that tore out his existing master bath. He has a custom sunken bath with a shower. Originally it appeared to have elastomeric waterproofing, but of course when they tore out the tile, it was damaged.

He hired a designer from a Tile distributor to come up with something special and he did. The designer (whom I was originally introduced as a tile contractor) had me tear out all the plywood with elastomeric and replace the plywood. I was hoping that was the end of my involvement, but I guess not. They were planning on hotmopping it, but the guy who does their work won't do bathtubs (too much water pressure). We had done another bathroom shower using the Schluter kerdi system and the owner asked me to do the tub.

I've never heard or seen using kerdi for a bathtub, so I'm assuming it's a no go. Am I correct? If I'm not, how do you handle the drain situation? This area has angled sides, a step, a bench, a adjacent planter and windows.

If this is a possibility, I'll get some pictures tomorrow. If it's not, what do you suggest? The tile guy has been no help.


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## ohiohomedoctor (Dec 26, 2010)

I wouldnt use Kerri for a tub. Id build it out of concrete board use a noble drain, and aqua defense that thing for days. 

That being said idk if id even do that. So many nice tubs on the market and I can't imagine a time tub being very cozy..


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## tjbnwi (Feb 24, 2009)

I've never heard of or seen Kerdi in a tub. This is not shown in the 2013 manual. Contact Schluter, never know what they may have done in there shop.

Swimming pool contractor????? Shotcrete and seal???

Tom


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## The Coastal Craftsman (Jun 29, 2009)

Wedi do kits for doing bathtubs.


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## redwood (Dec 5, 2007)

BCConstruction said:


> Wedi do kits for doing bathtubs.


 I didn't see anything, but some ready made box bathtubs. Nothing for custom shapes.


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## redwood (Dec 5, 2007)

I should say, the owner has no plans to use this as a bathtub, only as a shower. However it has the shape and originally was a combo, so he would like to keep it that way.


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## The Coastal Craftsman (Jun 29, 2009)

redwood said:


> I didn't see anything, but some ready made box bathtubs. Nothing for custom shapes.


You can buy the panels and build one. I have seen a few different designs done with it. Never done one my self though.


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## ArtisanRemod (Dec 25, 2012)

My first call would be to my Kerdi rep. You'd be surprised by the help they can offer.


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## country_huck (Dec 2, 2009)

Hydro ban by laticrete can be used for pools, and exterior water features as well as showers.


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## redwood (Dec 5, 2007)

country_huck said:


> Hydro ban by laticrete can be used for pools, and exterior water features as well as showers.


Yeah, but how about bathtubs?

I've seen lot's of products certified for showers, but none for bathtubs.


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## country_huck (Dec 2, 2009)

redwood said:


> Yeah, but how about bathtubs? I've seen lot's of products certified for showers, but none for bathtubs.


They state that it can be used for spas and hot tubs. If you have a beefy sprayer you can spray multiple layers on to build a nice thick even coat.


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## TRMolnar (Mar 19, 2012)

Hey redwood, 

I just took the schluter course back in October. They showed several options for making tub step and tub deck/surround using only kerdi board, but I remember them specifically saying not to use it for a bathtub... I imagine it wouldn't take the pressure. 

Best of luck!


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## ArtisanRemod (Dec 25, 2012)

This is just a surround, but I bet a tub could be done as well.
http://schluterkerdiboard.com/p/cumulus/ss_inst_kb_wanne_0009_r_rdax_495x331_90.jpg


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## TRMolnar (Mar 19, 2012)

ArtisanRemod said:


> This is just a surround, but I bet a tub could be done as well.
> http://schluterkerdiboard.com/p/cumulus/ss_inst_kb_wanne_0009_r_rdax_495x331_90.jpg


Thats the one! Our instructor actually built part of one... The stuff is amazingly strong for foam


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## ohiohomedoctor (Dec 26, 2010)

Been using kerdi board for years now. Great stuff..


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## mrcharles (Sep 27, 2011)

I think I'd steer them another way.


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## ArtisanRemod (Dec 25, 2012)

If Shluter supported it, I'd love to build one.


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## redwood (Dec 5, 2007)

I don't think that they will go out on a limb for this. I've also taken their workshop and I think they would have mentioned bathtubs if it was OK.


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## ArtisanRemod (Dec 25, 2012)

A fellow attendee in the 2.5 day seminar I went to in Plattsburgh asked about it and a rep said to give him a call. They might not advertise it, but you may be surprised what they will help you with. 
There certainly may be a better option here, but I'd love to see it done. Good luck with the project.


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## GO Remodeling (Apr 5, 2005)

redwood said:


> Yeah, but how about bathtubs?
> 
> I've seen lot's of products certified for showers, but none for bathtubs.


Pool, bath tub. What's really the difference?

Hydroban sticks to almost anything


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## Dan_Watson (Mar 1, 2008)

olzo55 said:


> Hydroban sticks to almost anything


So does gum..I wouldn't waterproof a shower with it though.


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## CarpenterSFO (Dec 12, 2012)

Schluter doesn't support kerdi in tubs or spas. I could swear that's been covered at length in a thread during the last year, but I couldn't find it.

Look at hydroban, or better yet, 9235, which includes a fabric membrane. This is a good (long) document from Laticrete on the whole subject: http://www.laticrete.com/Portals/0/pdf/DS-725.0.pdf.

Edit: The point being that Laticrete does support hydroban for use in a hot tub. We are talking about the inside of the tub, right? The Wedi bath box kits are for tub support decks/surrounds, not the interior of a tub.

Edit again: The liability exposure is significant. What do you need to do, and how much do you need to be paid, to warranty it as comfortably as you would warranty a nice Kohler tub? Thinking of it as a shower pan, only deeper, is a mistake, IMO.


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## GO Remodeling (Apr 5, 2005)

....


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## Dan_Watson (Mar 1, 2008)

olzo55 said:


> Guess Laticrete should discontinue selling Hydroban for pools,spa,showers based on your research.


My point was that just because it sticks to everything that it is the right product for every project....


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## GO Remodeling (Apr 5, 2005)

He should use the best product for the circumstances. Laticrete Hydroban is one of the best products to use for a free- form area.


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## redwood (Dec 5, 2007)

The owner decided just to make it a shower, unless I hear something real positive here.

Here are a couple of pics in it's present shape. We will backerboard everything and then kerdi.


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## The Coastal Craftsman (Jun 29, 2009)

redwood said:


> The owner decided just to make it a shower, unless I hear something real positive here. Here are a couple of pics in it's present shape. We will backerboard everything and then kerdi.


 Why won't you use wedi? You can make it what ever size and shape you like.


There's not much you can't make from it.


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## PrecisionFloors (Jan 24, 2006)

olzo55 said:


> Pool, bath tub. What's really the difference?
> 
> Hydroban sticks to almost anything


Kinda what I was thinking. If it's approved for a pool do they really need to tell you it will work in a bathtub?


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## redwood (Dec 5, 2007)

PrecisionFloors said:


> Kinda what I was thinking. If it's approved for a pool do they really need to tell you it will work in a bathtub?


They do me. Most pools are outside and don't involve wood framing.


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## CarpenterSFO (Dec 12, 2012)

redwood said:


> They do me. Most pools are outside and don't involve wood framing.


Laticrete has details for wood framing, but they include a mortar bed with metal lath - no details for Hydroban on Durock for submerged areas.


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## CarpenterSFO (Dec 12, 2012)

Ignoring for the moment how you'd get it in there, that geometry is pretty simple. I could imagine a welder making up a nice steel liner, stainless maybe, pretty easily. It's just a big kitchen sink. Not cheap, but not sky-high, either.


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## GO Remodeling (Apr 5, 2005)

Redwood, are you a Cali. guy? Isn't this a mud job?


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## GO Remodeling (Apr 5, 2005)

Neptuneb.com has Roman tubs that might fit


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