Natural Plasters

Started by Shelley, April 04, 2005, 01:36:03 PM

Previous topic - Next topic

0 Members and 2 Guests are viewing this topic.

Shelley

Talked to these people once at HBANM show.  Remember the prices as being a little high.

But they package a total product with standard colors.  This is far more workable than gypsum which sets up rapidly.  And they seem to have a few distributors in the NW and CA.  They're not as far "out there" as some of the proponents of natural plasters. ;D

http://www.americanclay.com/index.html
It's a dry heat.  Right.

Amanda_931

I'd seen their print ads, decided that they were probably very very expensive.

If, for instance you had a 10 feet on a side cube room, you would need 4-6 (the last including ceiling and floor) 50 pound bags or buckets.  Plenty shipping costs.

Just the colors (if you have white clay or they will keep their color in lime) are available from the Bioshield guys.

http://www.bioshieldpaint.com/catalog/default.php

Odd company, in my experience, and expensive.  A lot of people really like the oils for sealing earthen floors, even if they are two or three times the cost of hardware store linseed oil and mineral spirits.


Shelley

We went to their half day workshop this morning.
10-12 of us there.  Some professionals, tho they have an 8 hour one geared more to the pros.  One woman had come all the way from CA.

Product maybe not as expensive as I thought.  When they quote $1/sf that's  primer, 2 coats plaster, 1 coat sealer.  If new construction DW only has to be taken to level two.  Taped and dimples filled, but not the final pass one would do b4 texturing.  That makes it easier to DIY or the sheetrock bill less.

Can be used over gypsum, DW painted or not, cement, mud plaster.  Asked about blue board.  They had 1 complaint from one contractor saying that the paper delaminated.  Because of that they suggest doing what they know works.  Priming DW.

Wonderfully forgiving.  Can be patched and worked forever if not sealed.  Showed us all kinds of tricks and techniques for multicolors, shading, hints for application.  Stays wet for weeks.  Can be dried out, chunks stored, then reconstituted forever.

Discussed various topcoats of sealer, black soap, waxes and what the drawbacks were.  Found out you really don't need anything here except around the stove.  Back East maybe bathrooms.

No lime, no gypsum.  Can apply it with your hands if you'd rather.  Had a chance to use some of those pricy Japanese trowels.  They're worth some extra $$.  Dozens of colors.

This product is definitely DIY even if you've never plastered/stuccoed b4.  And, you can do a professional looking job.  I believe that.

Now I need some advice from Glenn and Amanda.  I've been reading up on mud plaster and I'm confused.  There's so much different info.  Can you point me to a simple concoction?  Ratio 70:30 sand to clay.  Then there's all this stuff about wheat paste, dung, straw and who knows what all?  Can you give me a simple recipe that works?  Point me to a source that will work?  Thanks.
It's a dry heat.  Right.

glenn kangiser

#3
Shelley -thanks for the workshop info.  The general rule I get is that there are not too many rules.  

The 70 -30 % is a pretty standard ratio for most earthwork.  I used variations of what was in Steen's straw bale house book for plaster.  I stabilized mine because I didn't want to keep redoing it and we get some driving rains here on the hill.  The stabilized that had sawdust in them and were less sand were not as durable -cracked but didn't wash away.  Totally exposed.  If moisture gets in and freezes it will damage it also - I think I will go to a clear masonry sealer over it to shed water too.  I've had good luck using stucco mesh with tar paper backing or even landscape netting with 30 lb felt behind for lath.  Experimenting, I sprayed the jute landscape netting with cement/sand mortar using a texture gun and allowed to dry making a reinforced wall I can earth plaster over.

Here is what I've had the best luck with - on the front wall behind  the last inspector picture.  It was about  70/30 including the claystone -gravel etc.  in the clay.  This worked out to about 4 clay 6 sand 5 handfuls of chopped straw -to stabilize add 1 Portland cement and 2 lime putty.  Mix well and have fun.  Rain or sprayed water does not wash this off although water will soak into it - thus my desire for masonry sealer - they use it on block walls of stores as water will go through block also if not sealed.  At this time I don;t know a good brand. Maybe someone else does -- then we'll both know ;D

You may have to experiment with  your soil mix -dry a sample then soak it to see if it is stable.  Charmaine Taylor recommends asphalt emulsion also - 5 to 30% - I have tried it -Henrys 107 - It works but unprotected it still has problems with freezing moisture below or unstabilized swelling clay below it breaking it.  Some of the old houses were simply given a new coat of plain earth plaster annually.  I haven't played with a lot of the more exotic ones yet.  We like the one I descrbed above the best so far.

"Always work from the general to the specific." J. Raabe

Glenn's Underground Cabin  http://countryplans.com/smf/index.php?topic=151.0

Please put your area in your sig line so we can assist with location specific answers.

Shelley

Ok Glenn.  I'll try yours.

American Clay's products are not suggested for outdoors, but  when you talk about stuccoing up to the top of the splash line and deep overhangs, they relax a little.

We're thinking about mud plaster on the exterior and trying their stuff on the inside.  Trouble is, it'll be  a big job since himself doesn't care for exposed adobe walls.  I like 'em fine.  So what to use for scratch/brown inside.  Could be cement or mud.  Their product will go over either.

We're both pretty jazzed about their products.  We don't get jazzed easily. ::)

Figured out that 2 coats of high quality paint costs $1.37/sf.  With reduced DW costs...if one is using DW...really not that much $$.

This is the same co that was featured in the latest Homes issue of FHB.  The pic that John posted in another thread.

BTW, they're using some of BioShield's products.  Searching for replacements because of the Euro.
It's a dry heat.  Right.


glenn kangiser

#5
I cut along both sides of the straw bale string with a chain saw to get shorter lengths of straw.  Don't cut the strings.  We prefer the straw showing on the outside of the plaster- even if you don't it makes something for a smooth coat to stick to.  I used 5 big handfuls per batch but you can vary the amount.  Our wall did not crack and we did it in two coats leaving off any fine finish coat.  I like it rough ;D
"Always work from the general to the specific." J. Raabe

Glenn's Underground Cabin  http://countryplans.com/smf/index.php?topic=151.0

Please put your area in your sig line so we can assist with location specific answers.

Shelley

I like it rough too. ;D

If someone wants it perfect, why go to all this trouble?  There are plenty of 20th century products that will make all sorts of things look perfect.  Much easier to look perfect.  Kinda like a hospital operating room.

But, there's a difference between old-world, time-worn, faded, soft and..... amateurish, botched, who-did-this-junk.

I'mtellinyaguys....if you've ever struggled with Venetian Plaster or a faux paint finish, check out this product.  I watched him put a little tint in a spray bottle, spray it on, trowel it out with a plastic trowel and achieve the most wonderful effect.

And, it was not because he does it every day as a lot of things are.  Truly believe that any of us can do it....it's that forgiving.
It's a dry heat.  Right.

glenn kangiser

I have save different colored clays when I find them to get different colored areas also - around here predominant tan color but some pretty dark iron reds to play with too.  A little can change a color quite a bit.
"Always work from the general to the specific." J. Raabe

Glenn's Underground Cabin  http://countryplans.com/smf/index.php?topic=151.0

Please put your area in your sig line so we can assist with location specific answers.

Amanda_931

I was doing a sample lime plaster once, forgot to tell my employee to add sand, it cracked and flaked off wonderfully.   ;)

I'd kind of expect a pure clay to do the same.

You can, of course, put a trowel finish on it--get the serious fine stuff to the surface.  Not sure what happens if you overwork clay plasters, but concrete will crack if you do it to a concrete wall (I'm responsible for some cracks on a strawbale wall in the Nashville area).

Keely Meagan the gal doing the interior plaster in that Building with Awareness DVD, has a booklet available from Charmaine Taylor at www.dirtcheapbuilder.com  She makes things pretty simple.

Cedar Rose Guelberth has the book.  She may be right to talk about all those other additives, but it sure gets complicated.

The really nice thing about that company is that they have premixed colors.  Not just red clay red.

Although there are supposed to be white and maybe green clays around here.  The white I have is in teensy balls in the silt up the hill.  I'm not going to separate it out to use.