Yeep, we plastered all weekend. Brian (6'5" tall helper) and I hit it Saturday morning. I'd prepped the two walls (sunroom-gold) and kitchen-green) last week, taped off the trim and walls and laid plastic on the floors keep the excess plaster from staining the unfinished wood floor. The walls needed some "tooth" to them to hold the first coat of plaster, so they got painted with a latex primer with about 1 pound of fine sand per gallon. Same sort of mix you'd use on a porch to make it slip proof.With calculator and kitchen scale in hand, I calculated how much plaster we'd need for the sunroom. American Clay advertises that a 50# bag of Loma (sandy base coat) will cover 200 sq. ft of wall. The 100% color was too much for us, so we started at 50% and it looked like shit (literally). So I upped the colorant to 66% and that was better, but the end result (when everything dried) as more like Gray Poupon. Its ok, but for the second coat (Porcellina), we'll go at 75% which will make the room "pop" a bit.
I mixed up 70# of loma using our bathroom scale to weigh the plaster. Then I weighed out the colorant, which comes in small bags. The Tucson Gold weighed 6.7 oz (190 g), so I needed 1.4x normal to get the right amount of color. Bought one of those little digital kitchen scales to weight it out; worked great. 266 grams of Tucson Gold and 70# of Loma. The bag says add up to 3 gals of water per bag, but I'd been warned that this would be too much. Right, we only used 11 qts (2.75) gals of water for 70# and it was a bit watery, so the right water mix is about 8 qts per bag. Your desired consistency is pudding: it should be stiff enough to hold a peak (like whipped cream) but not so stiff that its hard to trowel on (like peanut butter). With a bit of experience (like on Day 2), you can get it to pudding, remembering that you can always add water, but its hard to extract it (let it dry a day in an open bucket). Anyway, 70# mixed and off we went. I started in the sunroom and Brian started in the living room. Being a type A guy, I was slow. Brian whooped my ass on area covered, but my wall needed less refinement in the long run. You need a fairly smooth surface, complete coverage, and no buggers or divots. The leopard appearance on the gold wall is a result of uneven drying. The dark is wet, the light (final color) is dry.
The plastering went faster than I thought it would. An hour to prep and mix the plaster, 3 hours to trowel on the plaster (275 sq. ft), and an hour to clean up. Five hours total; I thought it would be more like eight. So Brian only got a half day of work in (no clean up for him)On Sunday, we went at it again on the bigger wall, the green kitchen. Same routine of mixing, but a bit more. On Saturday we only had about 1 cup of extra plaster, so I mixed a bit more than needed (I thought). We had 325 ft to cover, so I made 85# of mud. The green color is Verde (green) Valley and comes in larger bags (290 g). We mixed this color at 100% (508 g) since the sample I'd made at EcoHaus in Seattle turned out to be just right for the room. And in the long run we had 2 cups left over. What happens is that you start to watch the remaining amount of plaster and the amount of wall and start stretching it out, recovering plaster from the floor (if clean and on the plastic). Its tough mixing a partial bag, so running out is not a pretty option.
The green wall went faster since we were now pros (with 3 hours of experience each). Knocked off this wall in a little over 2 hours even though it as 50 sq. ft larger. So now that we've done 2 large walls, I'd figure we can lay up about 100 sq ft per hour (2 guys). Brian is about twice as fast as I am, but I tend to handle the edges and he takes the main walls on. We're half way through, so I expect we'll have two half days of work next weekend, then another day to compress the final clay coat. I'll save that for a later post. Back onto tile in the bathroom this week. Its about 75% laid on the floor, then grout and sealer. Nancy will tackle filling the hundreds of nail holes in the fir trim, sanding, and patching the polyurethane finish. Sounds like fun, so no bitching from me on the tile.
