"I love California Casa architectural vernacular because it accepts anything and everything," he explains. "It’s the ultimate eclectic architecture on the west coast—you can incorporate a lot of things into it."

To make the home feel more in keeping with the 1920s-era ones around it in Rancho Santa Fe, Leffers had added beams and swathed the house in Sherwin Williams's Greek Villa—which he calls the "perfect paint for stucco."

With that as a base, he looked to the interiors. "I wanted to add a dosage of Ralph Lauren WASPiness to accommodate my decorative arts obsession, and then surf shack to keep it casual and cool," the designer explains.

Hadley Keller for House Beautiful