An Innovative ADU Studio Enhances a Craftsman in Mill Valley

Mill Valley guest suite

Some home renovation projects are completed in a matter of months, while others can take years. A 1908 Craftsman in the Blithedale Canyon neighborhood of Mill Valley is decidedly an example of the latter. The 2,700-square-foot home’s renovation has spanned more than two decades, completed in multiple phases by two different owners — all overseen by architect Andrew Fischer. “I’ve been involved with this house for most of my architectural life,” says Andrew, who completed the first phase of the renovations early in his career before launching Fischer Architecture in Berkeley in 2006. 

When the first owner eventually sold the home, the new owners called back Fischer Architecture, now a husband-and-wife firm with architect Kerstin Fischer, to complete the last step of the renovation: transforming an unconditioned potting shed located beneath a wood deck into a flexible-use ADU with its own entrance that could serve as guest suite as well as a home office.

The first order of business was to rebuild and seal the existing deck to ensure it would be watertight. Then, the team set to work building the 650-square-foot structure, configuring the open-concept interior to accommodate an office, living room, kitchen, sleeping area and bathroom, and carving away a wall underneath a cedar archway to make way for the exterior entrance.

Mill Valley home, bed
A Murphy bed provides flexibility and saves space in the sleeping area.

When designing the structure, the Fischers came up with a creative plan to brighten the entire studio, including the windowless back corner where the sleeping area and bathroom are located. At the front of the studio, 11-foot-wide, floor-to-ceiling steel sash windows flood the combined living room and kitchen area with sunlight, and a steel-framed glass partition and folding door allow light to pass through into the office, which also features a large window. A track curtain cordons off the sleeping area when in use from the workspace, and a transom window brings natural light into the bathroom. “In what is very much an underfloor space far from the perimeter of the house, we managed to get as much natural light in as we possibly could while still creating separate spaces,” Kerstin says.

Mill Valley home, office
A steel-framed glass partition allows light to pass from the front of the studio to the office space in the back, which also features a large window.

In contrast to the upper level of the home, which features warm, natural wood finishes, the guest suite is designed with a lighter palette and industrial elements. Unifying the space, the Fischers salvaged and reused the Douglas fir flooring from the original potting shed and patched it where needed for continuity. Walls and ceilings are paneled in beadboard, echoing the material used on the underside of the exterior porch. To brighten the space, the walls, ceiling and kitchen cabinetry are all painted in the same shade of full-spectrum paint, an icy, smoky blue that appears to change with the light. “It’s kind of like the Marin County fog when the sun shines through — it’s not a gray fog but kind of that happy, blue fog we have,” Kerstin says.

The studio is located under the deck on the
lower level of the home.
Family heirlooms, antiques and collectibles on display.

Each space is designed with utility in mind — as well as aesthetics. The compact kitchen is outfitted with a sink; two-burner cooktop; convection oven; a small, concealed refrigerator and dishwasher; and painted-wood cabinetry. Carrara marble countertops and glass doors on the upper cabinetry elevate the design. The office features a jib door to the main living area upstairs that cleverly blends in with the beadboard wall paneling. In the sleeping area, a space-saving Murphy bed pulls down from the wall to reveal a recessed walnut-paneled “headboard” with niches for books and devices, as well as magnetic reading lights, and a TV on the opposite wall pivots to be visible from the desk in the office. The bathroom leans modern with unglazed, dimpled, large-format porcelain Pico tiles from Mutina on the walls and floors, creating the unexpected impression of making the room feel larger. A steam shower, Dornbracht plumbing and a custom mirror with storage and a walnut frame complete the design. Adding warmth and personality to each room, the studio is decorated with the owners’ family heirlooms, antiques and collectibles gathered during their many travels. 

A shadow of the trees outside through the shades.

“Fighting against any notion that this studio would feel like a basement was really germane to the initial program, and I think it’s quite an accomplishment to see just how bright and cheery it is down there,” Kerstin says.

Details

Where: Mill Valley

What: 650-square-foot studio ADU Architecture: Fischer Architecture


Lotus Abrams

Lotus Abrams has covered everything from beauty to business to tech in her editorial career, but it might be writing about her native Bay Area that inspires her most. She lives with her husband and two daughters in the San Francisco Peninsula, where they enjoy spending time outdoors at the area’s many open spaces protected and preserved by her favorite local nonprofit, the Peninsula Open Space Trust.