[duburban]

Whats the system that makes a plaster shower work? Assuming proper prep, whats the Substrate and Coating product I should look into? I'm assuming this will be a bag mix acrylic cement based product.

Whos product should I look into?

 

[Kowboy]

Google Schluter Systems

 

[duburban]

plaster over kerdi?

 

[CarpenterSFO]

Assuming this is over framing, not CMU:

Pool mix (white cement + white quartz or dolomite sand + lime + pigment + optional acrylic fortifier) over fiber-reinforced scratch and brown, on rib lath, over Stego Wrap over framing. 7/8" thickness at least, properly screeded.

Or pool mix over brown on concrete board over stego. Less durable than full mud coat, but requires less skill.

I'm not a big fan of plaster showers over wood framing. Plaster finishes also require maintenance to keep them looking nice, and will still show some age,which most Americans don't like. Plaster showers are great around the Mediterranean, where it's dry and the structure beneath (CMU or older masonry) can absorb a lot of water and not move.

 

[CO762]

Google Schluter Systems

So what you are advising him then is to put it over a waterproof membrane. Lots of those out there and none are magic, some just have better marketing programs than others.

CSFO's example is for containing water, that's 100% constant immersion. I'd imagine a stucco app would work here because, I mean, there are concrete showers, porous stone showers, etc.

 

[duburban]

Assuming this is over framing, not CMU:

Pool mix (white cement + white quartz or dolomite sand + lime + pigment + optional acrylic fortifier) over fiber-reinforced scratch and brown, on rib lath, over Stego Wrap over framing. 7/8" thickness at least, properly screeded.

Or pool mix over brown on concrete board over stego. Less durable than full mud coat, but requires less skill.

I'm not a big fan of plaster showers over wood framing. Plaster finishes also require maintenance to keep them looking nice, and will still show some age,which most Americans don't like. Plaster showers are great around the Mediterranean, where it's dry and the structure beneath (CMU or older masonry) can absorb a lot of water and not move.

this is way too much for me! but if thats how its done, i'll figure it out someday.

 

[CarpenterSFO]

...
CSFO's example is for containing water, that's 100% constant immersion. I'd imagine a stucco app would work here because, I mean, there are concrete showers, porous stone showers, etc.

My example is definitely not for immersion. Of course you're right about stucco; I've just upgraded it with a finish coat appropriate for a good shower, rib lath to keep it from cracking for as long as possible, and StegoWrap to deal with the water that gets through the plaster. You could get rid of the pool mix and make it more like concrete than a fine finish, and you could get rid of the rib lath and StegoWrap if you're going over CMU (in which case I would use Hydroban).

I am speaking from personal, practical experience. I've done exactly all that, on showers and walls, mostly tadelakt, just a couple portland cement plasters, interior and exterior. Having done some, and having seen some failures in plaster showers, I would be cautious about doing them at all, and ultra-careful when I did.

I haven't done any in a couple years - the market for luxury plaster work disappeared for a while, and me standing in a shower, covered in white plaster, using a trowel to aggravate my carpal tunnel syndrome, isn't where I'm trying to take my business. But I do watch that market, and I'm not aware that anything has changed the plaster business in the last few years the way the membranes changed the tile business.

Sorry to go on so long about it. I suppose I miss that business a little bit; it had its own moments of craft if not of art.

Edit: I'm also trying not just to be old-school about it. When it comes to tile, I'm 100% nu-skool, all about the orange stuff.

Edit again: I doubt I ever broke even on a plaster shower. Much too much work.

 

[duburban]

how has the tadelakt been for you? my sister ordered some to play with at one point and has a bunch of it still. impressive set of skills your have there SFO, is this thing common in your area?

 

[duburban]

As much as I like this idea I'm re-realizing that precasting gfrc concrete shower panels will give me better results more predictably.

 

[CarpenterSFO]

how has the tadelakt been for you? my sister ordered some to play with at one point and has a bunch of it still. impressive set of skills your have there SFO, is this thing common in your area?

As I mentioned in the other post, I haven't done any in a little while - actually we did a tadelakt outside wall last year, but no interior stuff in a couple years.

Done the old way, tadelakt is a great finish, but it takes a lot of labor and is therefore expensive. Most customers, in non-wet applications, are just as happy with one of the tadelakt-in-a-can formulas, which are really heavy-bodied paints.

I get inquiries about it but scare them all away when I talk about price.

 

[CarpenterSFO]

As much as I like this idea I'm re-realizing that precasting gfrc concrete shower panels will give me better results more predictably.

Does that mean you'll install panels, then put a finish coat on them? Or pre-cast whole walls?

I'm still curious about the project; this is residential? What sort of home? Pictures?

 

[CO762]

I assumed it was for his own home. Yeah, that type of stuff is a real niche, sort of like real wood cabinetry I guess. Same with mudwork....most residential units it's not worth it to them, no you.
Stuff like that is craftwork, not a "trade", if that makes sense.

I've seen showers that were made out of coated plywood, and judging by the age of the rest, it's been going on 4-5 decades and still working fine. I've also seen frp, and I assume that is over greenboard that's also been up for a few decades too. And they used to make boats out of plywood...still do, but not production ones. I've always said that if the waterproofing works, it doesn't matter what's behind it...waterproofing wise.