Mary Blodgett and her husband, Carlton Calvin, came close to demolishing their modernist home in a leafy suburb of Los Angeles after buying the land in the mid-2000s. The single-story house in San Marino had been designed in 1954 by Calvin Straub, a leading proponent of Californian modernism, but it was falling into disrepair. The couple had even gone as far as to commission plans for an ambitious new home for the site before they eventually decided to remodel it and build a series of pavilions on the grounds.

“The main house has a kind of structural rhythm,” says Alice Fung, a founding principal of Los Angeles–based Fung + Blatt Architects, whom Blodgett and Calvin enlisted to lead the sensitive restoration and redevelopment of the estate. “We came to understand that rhythm and...