No coat of paint can match the richness and depth of color that clay plaster provides. Combining ground clay and water with natural pigments, it’s the easiest of all plasters to apply, though it still requires muscle ― beginners should start with a small accent wall. You can layer it over previously painted walls or new wallboard, as long as the surface has been prepped with sanded primer formulated to allow the clay to bond.
Working with a steel trowel, San Francisco contractor Orit Yanai demonstrates the application process. “The only thing that really matters is applying it in a credit card–thin coat,” she says. “Too thick and it will crack.” Clay-plaster walls can be used throughout a house ― moisture doesn’t harm them. The nontoxic material resists mold, emits no volatile organic compounds (VOCs), and will not fade.
Resources: American Clay Enterprises (clay and pigment; 866/404-1634 for stores); BioShield (clay-and-pigment mixes; 800/621-2591); and Portola Paints and Glazes (mixes; 818/623-9053). Orit Yanai teaches clay-plastering in California and New Mexico (415/264-5577).