Bill Gawthrop and Diane Taylor might live in the only house that is deliberately designed to look as though it has been through an earthquake. Their home, located on a ridge in Northern California’s Mendocino County, has a diagonal “fracture” near the front door that shows how the earth could have shifted. This nod to geological stress is appropriate, given the couple’s professions: They are geophysicists, now retired.

Overall, the 2,700-square-foot house is a triumph of building science, a modernist dream home that is also completely off-the-grid and net-zero.

The person who figured out how best to express the couple’s scientific bent was designer Alan Nicholson, who is based about an hour away in Ukiah. One of the first things Nicholson suggested was to excavate a grassy knoll in order to create an exposed rock formation right at the entrance to the house. “When we heard that, we figured Alan was sufficiently crazy and that we could probably work with him,” Gawthrop jokes.

The house itself is long and thin, an unusual combination of rammed-earth walls—inspired by Gawthrop and Taylor’s time spent living in the Southwest—and a huge amount of glass. The transparency helps with climate control. In winter, low sunlight passes through the south-facing windows and heats the thick earthen walls on the north side; in summer, the glass is shaded by deep overhangs, so the walls insulate against the heat.

Given the home’s subterranean appearance, its interiors are surprisingly lofty. The cedar-lined ceiling appears to float, supported on thin steel beams and cable trusses in place of bulky girders.

“You get the heaviness of the rammed earth but the lightness and airiness of the floating roof, and it creates this dynamic effect,” Nicholson explains. Says Taylor, “We like looking at the structure of things.”