An open floor plan nudged Heidi Caillier to use paint and paper to define rooms (and vibes) in her client’s Mill Valley, California, home. Drenched in a cosseting blue-gray (Down Pipe by Farrow & Ball) and furnished with a Howe London sofa (in a Robert Kime fabric) and deep George Smith chairs (in a Colefax and Fowler windowpane check), the family room is a siren’s call for cozying up. Ottoman, Guy Goodfellow; chik blinds, Virginia Tupker.

Haris Kenjar

Heidi Caillier Designs a Storybook Mill Valley House With a Plot Twist

The designer steeped an 1896 fishing retreat in moody hues, cottage-charming textiles, and vintage gems.

October 13, 2025

When California was wild, it was the most flower-filled part of the continent, said the naturalist John Muir, whose name graces a primeval redwood forest that lies just north of San Francisco and west of an old home that now blooms for a young family. Like the California of yesteryear, this Mill Valley house is also awash in florals—specifically in the form of pattern, put there by the hand of decorator Heidi Caillier, who cultivated this space to be native to both its new owners (a pair of Marin County natives with three young children) and its locale. “While I could say that our style is Americana, Shaker, modern traditional, warm, collected, or even farmhouse, I’d really prefer a home that is simply ‘of Mill Valley,’” the client initially told Caillier. Settled (and named) for the first sawmill in the region, the area saw a boom of vacation residences just before the turn of the 20th century. 

A Tim Page rug adds natural texture to the family room.

Haris Kenjar

A vintage painting from Pierce & Ward hangs above the fireplace. George Smith chair in a Colefax and Fowler plaid. 

Haris Kenjar

A vintage scissor lamp illuminates a nook. Pillows in a mix of fabrics from Lisa Fine, Holland & Sherry, and vintage. Throw, Matouk. 

Haris Kenjar

This particular house was created as a fishing retreat in 1896, its walls insulated with pages of the San Francisco Chronicle. It’s the stuff of dreams for Caillier: The Seattle designer’s work is long on nostalgia, real or created; her rooms have a storybook quality to them that’s not about quaintness, but an out-of-time wholesomeness. In these spaces, you might feel a twinge of hesitance to pick up your phone, as if this world has better plans in mind for you.

Farrow & Ball’s Coppice Blue provides a “grounding element” for the dining room, with walls of windows looking out over the yard and pool. Gregory Parkinson blankets dress the table, which is surrounded by Sawkille chairs. Chandelier shades, Matilda Goad.

Haris Kenjar

Robert Kime sconces flank the vintage tramp art mirror in a powder room. Wallpaper, Marthe Armitage.

Haris Kenjar

The kitchen is light, airy, and timeless with statuary marble and wood counters, vintage pendants, and an antique rug. Sink, faucet, sconces, and stools by DeVol.

Haris Kenjar

“There’s something soft and gentle about this project since the homeowner is a very nostalgic person, as am I,” explains Caillier (pronounced KAL-ee-yer). “We wanted it a tiny bit sweet, but also a little bit rustic, like it had been there forever, with everything a little bit wonky and not pristine.” It starts with the architecture, she says. “A good builder will home in on details right down to the eighth of an inch, but I’m constantly saying, it doesn’t have to be perfect—life isn’t perfect!” Here, sconces are slightly askew, and the bamboo chik blinds hang a teensy bit lopsided. The looseness lets life in. “That’s the thing about creating imperfection,” says Caillier. “It’s very intentional.”

Caillier conjured a treehouse vibe in the primary bedroom, which is swathed in Light Blue by Farrow & Ball. The Hollywood at Home bed is dressed in D. Porthault sheets with a blanket by A Little Weather. The Cisco Home sofa is covered in a Penny Morrison fabric; Samarkand shades top the Penny Morrison lamps.

Haris Kenjar

Voodoo by Portola Paints, a pale mauve, feels softly sophisticated in the primary bath. The vanity is by Drummonds; sconces, Hector Finch.

Haris Kenjar

Rustic stone tiles by Exquisite Surfaces and natural accents like the Virginia Tupker blinds bring the pastel color down to earth.

Haris Kenjar

Next she called in fabrics and lighting by Brits such as Robert Kime, Rita Konig, Ben Pentreath, and Marthe Armitage. That cadre of charmers made quick work of plucking this house from the 2020s and placing it in a hazy, romantic past. Would-be froufrou details like a ruffle-skirted sofa or scalloped lampshades work here because Caillier keeps things balanced at every turn. In the inky mallard blue family room, the color drenching, muscular George Smith chairs, and rustic jute rug prevent sweetness from turning saccharine. Upstairs in the pretty, plaster-pink primary bathroom, old limestone floors and a vintage wood stool keep the scheme “from going over a cliff,” says the designer.

Hamilton Weston floral wallpaper wraps a daughter’s room. Bed and desk, Chelsea Textiles.

Haris Kenjar

A Virginia Tupker bed and a vintage quilt add a rustic note to the Marthe Armitage botanical wallpaper.

Haris Kenjar

Brass Nickey Kehoe sconces, sink fittings by Water Monopoly, and Rejuvenation cabinet hardware warm up the daughters’ bathroom.

Haris Kenjar

The guesthouse engendered no such fears. The 600-square-foot space joins the main house via a central corridor but is independent enough to exercise its own personality. Beautifully, it was right there for the taking. Early conversations unearthed a strain of Sea Ranch style, named after the 1960s Northern California coastal community known for its pared-back, barefoot-modern, cedar-clad houses. The concept seduced both client and designer, becoming the ideal jumping-off point for the cottage’s aesthetic. “It was one of those moments that took off right away,” says Caillier. “No hesitations!”

“We wanted the vibe to be a bit different—more modern California,” says Caillier of the adjoining guesthouse. The white oak–paneled dining room leans on sculptural shapes, from the Commune for Remains lighting to the custom cabinet to the vintage Kjaernulf chairs.

Haris Kenjar

A Hollywood at Home blanket and tacked-up linen curtains feel decidedly bohemian in another guest quarters.

Haris Kenjar

Sleek is the word in the guesthouse bathroom, with its wall-mounted Waterworks faucet, Remains sconces, and Clé floor tile.

Haris Kenjar

Tapping into the realm of NorCal hippie-modern, Caillier created a pert box lined with white oak, a few Danish modern furnishings, natural linen and burlap, and lighting by Commune. A thread of the living room’s deep blue winds through, offering a reminder that the ocean is a mere 10 miles away. Still, the story here is rooted in wood. It’s Mill Valley, after all.

A ladder leads up to the sleeping loft.

Haris Kenjar

THIS ARTICLE ORIGINALLY APPEARED IN VOLUME 18 OF FREDERIC MAGAZINE. CLICK HERE TO SUBSCRIBE!