We’ve been covering the main lodge with natural fiber plaster (it’s earth based, with straw, fine sand, and wheat paste in it), and then adding alis over that. The two coats of plaster were great, but the aliz smoothed over the plaster and it gets “polished” with sponges, leaving a hard surface–and it held up beautifully in the first rain and snow.
The trick with the alis is to get the mix right–enough clay and water to stick, enough fine sand to hold, enough wheat paste to want to shed moisture. The mix we’re using now is 5 quarts clay to 4 quarts water and 4 quarts sand and 1 quart wheat paste. The bottom of the mix pail often needs about 1/2 cup more water–it’s painted on so if it’s not going on smoothly, a little more water is needed. The mix changes based on the weather–wet sand obviously needs less water, while very dry clay and sand needs a cup more.
In addition to this, we’ve added rocks (all gathered from the land) around the base of the wall to encourage good drainage and also it looks nice–you don’t want your plaster to extend down to the ground where it can wick up moisture, so you end up having the footer visible. The rocks nicely cover the footer.
On the top of the buttress walls, where we have more exposure to weather, we put on Mexican roof tiles that we found at Habitat for Humanity Re-Store for only $2 each. The Re-Stores are one of our best resources not just for affordable materials, but materials that otherwise might have ended up in a landfill.
We’ve also started to add art to the walls–in the protected areas.
This is a revised clay recipe from the book, Clay Culture, which uses shredded paper in the mix (to replace some sand and straw). The paper makes the clay easier to manipulate. On top of that we add some pigments from BioShield Paints (see more on the artwork in another recent post).