Casa Caldera, designed by DUST, is an off-grid house located in a remote landscape on the south-western bajada of the Canelo Hills in Southern Arizona’s San Rafael Valley. Created to have an impenetrable construction as well as to blend in with the environment, the house is made of lavacrete, a variation of concrete.

The house emerges from the native grasses and open ranges beyond in a simple rectangular form of 18 inch (46 cm) mass walls constructed of poured lavacrete, a process and product refined by the material’s pioneer, Paul Schwam, and used in the region’s architectural community, notably by Paul Weiner and Design Build Collaborative. The material is comprised of a mixture of pulverized lightweight red scoria, cement, and water, rammed into formwork. These walls create the structure, finish and offer insulation and thermal mass all in one stroke.

The 945 square foot structure takes clues from a vernacular “zaguan” housing typology. A zaguan is a passageway leading from the entrance door to the central patio in houses commonly found in the southwestern U.S. and Mexico. The plan locates two bedrooms of 265 square feet (25 square metre) opposite a living room of also 265 square feet. A zaguan runs between the rooms. Large bi-fold doors on the ends of the zaguan connect the space to the outside, introducing natural light when open, and security when closed.

Cooling is provided by natural cross ventilation through the zaguan and window openings, while wood fuel sourced on the property provides heating. Water is from a well, while solar power is used for minimal electrical and appliance needs. A single 30-yard (27.4 metre) rolloff of waste was removed after the entire construction process.

Photos: Cade Hayes (via v2com)