Marin County Round Roof – Futuristic Roofing Design of the Atomic Age

New Roof for Marin County, CA Atomic-Age Home

As if hovering high above the San Francisco Bay, the circular atomic-age home is perched 900 feet above the waterside town of Sausalito in Marin County, CA needed a high-tech roofing solution. Built upon a cut terrace, at the top of the Marin Headlands, parallel with the 746-foot south tower of the Golden Gate Bridge, the redwood and glass home was designed by famed mid-century modern architect, Mario Corbett, in 1954.

Bay Region Architect

In the post-war years, from the 1940-1960’s Mario Corbett was a renowned leader of the Bay Region Style of Architecture, wherein mid-century modern design was adapted to blend harmoniously with the Bay Area’s unique climate and sites. Corbett designed many homes on the Marin Headlands, including his own Wolfback Ridge house which received the AIA Award of Merit in 1949. Unique to their sites, each Corbett custom-designed home accentuated the incomparable views while providing protection from the fierce Pacific Ocean winds and fog that pour over the coastal cliffs. 

Roofing in the Round

Atomic-age “Round Homes” offered a futuristic design in direct contrast to the post-war tract divisions of “little boxes.”  However, just as in the “Geodesic Dome Boom” of the 1970’s, the “Round Homes” challenged builders, and especially roofing contractors, as traditional roofing systems cater to rectangular structures, rather than circular roof designs. Because of these challenges, flat round roofs often failed their waterproofing function resulting in interior water intrusion. Furthermore, conventional roofing systems lacked the necessary thermal performance to properly insulate the home. 

High-Tech Roofing Solution

A custom designed Spray Foam Roofing system provided the perfect melding of high-tech roofing technology with mid-century architectural design to meet the needs of this atomic-age home.  Sprayed-in-place, the liquid applied application of closed cell spray foam conformed to the radius, expanding into a solid, seamless roofing membrane. This highly-insulating, waterproof spray foam roof surface was then covered with a protective silicone roof coating providing reflective properties as a cool roof. Now this spectacular Mario Corbett designed home is securely waterproofed and thermally insulated for summer days when the fog rolls over the Marin Headlands. 

Mario Corbett designed the Sausalito “Round House” for Marin County Real Estate Developer Walter Benson and his family. Benson and his wife are pictured hosting a 1959-era cocktail party.

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“They built the turret in the sky – a round home in redwood and glass in which every slightest turn of the head brings a new, breathtaking view.  To live way, way up on the top of a mountain in a house that seems to melt in with its surroundings; to look freely all about you and see the mountain ridges to the side, the bay and ocean below, and the teeming city across that you must be a part of and yet can turn away from at will – this was the dream of the Bensons, of suburban Sausalito.” Suburbia Today Magazine, July 1959