Guys, I think I have given up on the MGO board industry for now, too unstable for my interior walls. I'm thinking clay plaster and all I found so far is a distributor out of NM named "American Clay" costly to ship to me and I bet I am @ $3.00+ SF installed @ 1--2" thick, maybe more. They have a "Proprietary Blend" so who knows how much and what type of clay and IF I get the Hygroscopic thermal mass I want out of interior walls. I have one installer mainly experienced is commercial grade synthetics and some lime old building restorations, but no clay plaster experience. I don't know how much of a learning curve there will be but I hear he does good work. American clay also recommends burnishing and lime wash or plaster finish coat for durability, depending on how smooth a finish which I want to offer all to my clients. I'm thinking burnished/smooth on specs since that is what people are use to, or semi-smooth.
I have a local ceramic shop that I can get Kaoline, Bentonite, Pumice, or most raw materials for a decent price around $1-2/pound, no shipping, but do not know of a good mix. I'm thinking if I can find a good mix for my installer to do on site I can get my cost down closer to drywall/paint at around $1.50 SF I don't want to use unless budget drives me there. Our soils can vary too drastically, and I'm only digging footing's that will probably end up for padding and drainage.
I need a wet mix too for bathrooms, custom showers, etc...
I don't think metal lath is good, I'd prefer wood but what kind? I have 2x6 on 24 OC maybe Timbers if not too costly, mineral wool insulation.
Any ideas on a mix or a supplier close to KS or that has good prices after shipping and that discloses clay type and percentages, has indi tested physical/durability properties like max moisture content and perm rating, impact and liquid water resistance, does not hide the levels of cost reduction fillers, AKA "Propriety Blends"?? ..that need more testing and available public evidence then anything on their site as Architect info....not much better than the American MAG board industry IMO. Suggested DIY mixes no guessing same level of test are needed please post results from indi or some monitored results from one of your homes you designed and built. If you do not mind please provide the location of the build and an address or contact me with the info. I'd be glad to open a dialog wth a builder that has proven results I can verify as well as I can share mine.
I've applied a lot of different natural plasters; they each have their own merits and each their own disadvantages. It just depends on what your desired finish is and what substrate you are going to apply it on.
I think if you want a cheap and fast alternative to drywall and latex, you can't beat lime and marble powder applied directly to bare drywall. Two coats are required to achieve a stunningly beautiful Tadelakt/Marmorino finish. I typically use a 1:1 mix. This is a very good wet area interior finish, but for exterior I would use a lime/pumice mix, LimeStrong has the very best for about $0.40/lb.