California’s House site is spectacular, a steep north-facing hillside with unobstructed views of the San Fernando Valley and the mountains. Building on the site, long considered unbuildable, presented two challenges: first, to minimize the impact of the house on the landscape and second, to create sufficient flat area to be comfortable for outdoor activities. The solution—a contemporary nod to the original Case Study Houses of the mid-twentieth century that uses the landscape to reduce energy consumption—bifurcates the building into distinct tectonic halves and programmatic functions: an open-floor pavilion at the top and concealed private spaces carved from the earth below.