Spiegel Aihara Workshop transforms a midcentury Mill Valley home into a bright sanctuary for everyday living.
Materials employed by the design team convey a smooth visual transition between indoors and outdoors.
It’s pure serendipity when an architectural team works closely with a homeowner who is a renowned interior designer. That’s exactly what happened with a Mill Valley home owned by Kina Ingersoll, principal at Kina Ingersoll Design (@kinaingersoll), and her husband, Bill. They share their 1962 Mill Valley home with two young children; its spaces were small, chopped up and possessed many organizational flaws. The couple loved the home’s horizontal facade and good bones but wanted to open up the 2,746 square feet into airy, functional rooms.
The couple chose Dan Spiegel and the team from Spiegel Aihara Workshop, or SAW (sawinc.com), a San Francisco-based architecture and landscape architecture firm. “Bill and Kina are extremely sophisticated clients, so this process was highly collaborative from the start,” says Spiegel. “We knew we would preserve as much of the periphery as possible and focused on solving the complicated and often conflicting alignments in the middle. We love projects with no immediately clear solution, so we set out quickly cycling dozens of iterations for the initial design concept, from sketches to 3D models, using these tests to define the project parameters and build a dialog about project goals with the clients.” The project became known as The Middle Half, as it dramatically reconfigures the home’s core to create an open, light-flooded interior and direct connection to the landscape. SAW eventually expanded the living space to 3,457 square feet.
Built-in bookshelves display art collected by the family during their many travels.
Ingersoll says her design philosophy encompasses authenticity, minimalism, neutral palettes and a connection to nature. “Aesthetically, my goals were to create open, serene and tranquil spaces grounded in clean lines and the beauty of natural materials while also highlighting the beauty of the home’s natural surrounding environment,” says Ingersoll. “I wanted the kitchen and dining area to be the heart of the home. These are the focal points and hubs for the other rooms and spaces. I also wanted to seamlessly incorporate the home’s collection of worldwide cultural art throughout the spaces.”
Spiegel notes the site was constrained by the mismatch between the old structures and the current setbacks and a significant slope toward the back of the lot— complicating the zoning envelope. “We had to thread the needle to make all the heights work, from the subtle, layered alignments of the structural system to the reveals between materials to the sense of height in the living room to the low-slung exterior massing from the street,” he says. “There were hardly inches to spare in any direction.”
The design team opened up the center of the house to allow easy flow from one room to the next, while reclaimed white oak wood plank flooring ensures a seamless aesthetic.
Exposed Douglas fir ceiling joists and reclaimed white oak wood plank flooring bind the revitalized interior spaces together. “We sourced the flooring, which came from an old barn in the Midwest, from Restoration Timber (restorationtimber.com), and the floor-to-ceiling glazing and sliding doors are by Fleetwood (fleetwoodusa.com),” says Ingersoll. Standout pieces in the living room—boasting natural materials like leather, wood, metal and wool—include a custom sofa, a Minotti (minotti.com) coffee table, Blu Dot (bludot.com) lounge chairs, a vintage milk bottle side table and an Icelandic lamb rug.
The family room serves as a space for game nights and watching TV. “The built-in bookshelf is the same material as the flooring throughout the home—reclaimed white oak wood plank flooring—and houses many of the books, art, and musical instruments we found while traveling,” says Ingersoll. “The custom sofa sits on a wool braided rug from HD Buttercup (hdbuttercup.com). A Serge Mouille (sergemouilleusa.com) three-arm ceiling light is centered on the ceiling, and a vintage round table sits in a corner surrounded by contrasting modern Panton chairs Vitra (vitra.com).
“The dining room is grounded by a custom-designed, live-edge Claro (clarofurniture.com) walnut dining table and is defined by the white concrete pendant light fixtures above the table” crafted by Greek designers, says Ingersoll. Molded Eames chairs from Herman Miller (hermanmiller.com) surround the table. Masks from Chile, Fiji, Nepal and Morocco also grace the room.
“The kitchen cabinets disappear so that the handmade Sonoma (sonomatilemakers.com) tiles on the backsplash are the focus of the space,” says Ingersoll. The counters and island are lined in Caesarstone (caesarstoneus.com), the light fixtures above the kitchen island are Aplomb by Foscarini (foscarini.com), and the sink is from Kraus (kraususa.com).
The room, which also doubles as an office, boasts the same exposed Douglas fir ceiling joists, reclaimed white oak wood plank flooring and floor-to-ceiling sliding doors by Fleetwood found in the main living spaces. The bookshelves and bed frame are from Room and Board (roomandboard.com), while the Ingersoll sourced the vintage bench at the foot of the bed from HD Buttercup. “A full-length mirror with a heavy wooden frame from Santa Monica’s Marco Polo Imports (marcopoloimports.com) hangs on the wall next to our closet,” she says.
The home’s profile reveals openness and connection to nature, which was the homeowners’ goal for the project.
Ingersoll believes the project succeeded because of the collaborative momentum she developed with Spiegel and his team. “I would convey a vision for a space, and Dan would respond with a few structural design concepts, which I would noodle over and then expand, refine or follow to a new idea until we landed on the right solution,” she says. “It was truly an amazing partnership that quickly grew into a strong friendship.”
Initially, Ingersoll worried that the interior stairwell would feel claustrophobic, especially in contrast to the wide-open spaces of the first floor. To minimize this effect, the team opened up the back of the bookshelf from the family room, doubling as the stairwell’s wall. “It worked because opening up the bookcase—and therefore the stairwell—let natural light fill it, creating a more open, relaxing aesthetic,” she says. “After settling into the home, we found another unexpected benefit: The open bookshelf created sightlines from the family room to the kitchen, connecting two spaces that would have otherwise been separate and divided. This was a surprise for us, as it visibly enhances the home and strengthens the overall goal of the project: openness and connection.”
Native grasses and other plantings frame the Mill Valley home.
Home Type
Single-family
Location
Mill Valley
Architecture & Landscape Architecture:
Spiegel Aihara Workshop (SAW)
sawinc.com
General Contractor
Perfection Construction
perfectconstruction.com
Millwork
Marco Hernandez
Custom Cabinetry
hernandezcustomcabinetry.com
Interior Design
Kina Ingersoll Design
@kinaingersoll
Restoration Timber
Flooring, living spaces
restorationtimber.com
Fleetwood
Doors throughout
fleetwoodusa.com
Minotti
Coffee table, living room
minotti.com
Blu Dot
Lounge chairs, living room
bludot.com
HD Buttercup
Rug, family room; bench, primary suite
hdbuttercup.com
Serge Mouille
Lighting, family room
sergemouilleusa.com
Vitra
Panton chairs, family room
vitra.com
Claro
Table, dining room
clarofurniture.com
Herman Miller
Eames chairs, dining room
hermanmiller.com
Sonoma
Backsplash, kitchen
sonomatilemakers.com
Caesarstone
Counters, island, kitchen
caesarstoneus.com
Foscarini
Lighting, kitchen
foscarini.com
Room and Board
Bed frame and bookshelves, primary suite
roomandboard.com
Photography by: MIKIKO KIKUYAMA
