DESIGNING FOR ECOLOGY AND COMFORT IN THE MOJAVE DESERT

Mesa Sky Disk, a recently completed strawbale structure in California's Mojave desert, was designed for low carbon impact by Berkeley-based Leger Wanaselja Architecture. In coming years, a significant number of greater Los Angeles' estimated 20 million people will move inland to desert regions. Given the challenges of building appropriately for the extremes of the high desert, the Sky Disk collaborators were eager to use this building as a lab for emerging techniques that reduce carbon and toxic materials, while still exceeding stringent California standards for seismic code and energy efficiency.

According to the architects, "Like two petals on a flower the two sides of the house rise out of the desert inclining toward the rich and subtle vistas of the Mojave Desert. Built with strawbales, which lend themselves to the curved form, and other natural insulation like blown in cellulose and lava rock, this building creates a refuge from the dramatic temperature extremes typical of desert life."

AVOIDING TOXIC MATERIALS BY BUILDING WITH STRAWBALE

The building's strawbale walls are more than half a meter thick, built around a core of clean barley straw provided by stawbale builder Cadmon Whitty, from a specialty grower in Colorado. On either side of the bales the walls are finished with three coats of plaster, including natural lime from St. Austier, France. This lime forms a mortar with water without requiring cement, gypsum, ash or other common additions to modern stucco.

To promote air movement and quality no vapor barriers or toxic materials are used within the straw walls. The walls rest on untreated redwood sills rather than pressure treated lumber to ensure no tebuconazole, arsenic, formaldehyde or fungicides enter the living space. The house is designed with non-toxic materials so that the building's water runoff is not compromised for plants and animals on site. Boulders on the East side of the cabin form the perimeter for a cask for the building's own construction waste, in order to minimize the landfill required to build the house. This area was designed to be finished as a patio using pavers made on site from construction surplus.

SEQUESTERING LANDFILL IN THE FOUNDATION

The building’s board-formed foundation uses a very low fly ash concrete recipe, and a unique engineered void within a rebar cage, both to lower embodied carbon. Many tons of salvage materials, from old radios and appliances to car parts, are sequestered within this engineered void to remove them from landfill. The architects help collect this infill, choosing items that cannot be reused, do harm to the environment as they disintegrate in the elements, but are not reactive and therefore can be encapsulated in concrete safely. This building is the first we know of to engineer this approach into the foundation design.

DESIGNING WITH NATIVE PLANTS AND WILDLIFE IN MIND

The project is sited on a 20,000 square meter lot adjacent to hundreds of acres of unbuilt land. Out of respect for the environment, no vegetation was moved to accommodate the house. The structure's footprint was intentionally designed to the 70 square meters minimum allowed by the town of Yucca Valley. The building's size and siting are meant to encourage existing wildlife corridors on the property despite the human additions to the land. Grading was kept to a minimum for the same reason.

The site is unusually rich in native flora, including Joshua Trees, many cacti and yucca, sages, brushes, as well as edible and medicinal plants. Some of the vegetation, including Blackbrush, can live for more than 1,200 years: their density on site attests to many tens of thousands of years of propagation. The building itself is contoured around a group of Joshua Trees, including more than twenty pups which are increasingly rare as the climate changes. No plantings have been added on site, to preserve the existing ancient forest.

The strawbale house on Yucca Mesa was completed in 2024. For more information please contact Kevin Cain, kevin@insightdigital.org, https://skydisk.shop/.  For booking, please see: https://www.airbnb.com/rooms/1273329079275800052.