The house at the end of Studio Drive doesn't look radical. It looks like a low concrete wall with too many windows. From the beach, it looks like it grew out of the bluff. That was the point.

Architect Lena Chu spent three years developing a building technique that uses dried bull kelp — harvested from the beaches after storms — as insulation between poured-concrete panels. The R-value is comparable to closed-cell foam. The carbon footprint is negative. The smell, after the first rain, is "oceanic in a way that grows on you," Chu says carefully.

The Cayucos Planning Commission approved the build in 2024 after a contentious 4-3 vote. Neighbors called it "a bunker." Chu called it "the first house that actually belongs here." After two winters, the kelp panels have held. The heating bill last January was eleven dollars.