US studio Faulkner Architects has clad a low-profile mountain house in corrugated Corten steel for wildfire resilience in Northern California.

Known as the Pine Flat Residence, the three-bedroom house is spread over two storeys and is embedded in a steep slope in Healdsburg, about an hour north of San Francisco.

The remote site was originally the home of an off-grid house that was destroyed in the 2019 Kincade Fire.

Pine Flat Residence is a home in California designed by Faulkner Architects

The clients hired Faulkner Architects, which has offices in California and Colorado, to create a durable, low-maintenance home with a long lifecycle, embracing the character of the nearby Pine Flat community, a boomtown in the Mayacamas Mountains that flourished with quicksilver and mercury mining in the 1870s.

It was designed to emphasise the landscape and be durable in the event of future fires.

"This project exemplifies how residential architecture can transcend aesthetic considerations," Faulkner Architects said, explaining that the house is a tool for living on the site. "As we continue to expand into wild landscapes through development, we must enhance construction systems and materials to withstand disasters."

It was topped with a sloped shed-like roof

Faulkner Architects reused the existing concrete foundation and walls of the destroyed house to retain embodied energy and limit excavation on the steep terrain.

A long volume with a shed roof that mimics the slope and aligns with the ridgeline. The garage angles out from the rectangular main house and caps a workshop space that is embedded into the hillside on the lower level.

Corten steel clads the home's exterior

"Like stepping on a leaf, portions extending beyond the outline of the new rectangle are utilized for a sculptural entry step as well as a glazed light well," the studio said.

"The preserved concrete foundation is half buried into the hillside, juxtaposed with the outstretched protective structure elevated above."

Designed for accessibility, an entry ramp extends from the western access point to the main level with the primary bedroom, living and dining spaces.

A pre-framed elevator core allows for wheelchair access – when needed in the future – to the lower level with extra bedrooms, service spaces and areas for the residents to be creative.

An outdoor porch wraps the upper level

The upper main level centres a concrete chimney in a wall of windows that open to a wrapping porch – a reminder of the fire, the studio explained.

This is juxtaposed with an artesian water basin on the west side of the house that "fosters a visual and poetic dialogue to honor the site's spring water".

The fire-resistive Corten steel shell, sliding ember screens and exterior sprinklers over the decks were all put in place to mitigate the risks of fire damage, while the home uses off-grid utilities – including an upgraded solar array – to embrace passive survivability.

The house replaces a home that was destroyed in the 2019 Kincade Fire

In addition to wastewater treated in a septic field, the design captures and retains 100 per cent of the site's stormwater with a cantilevered gutter that flows into a steel basin, diverts runoff to a bioretention area and cascades into a retention pond that can be used as a backup firefighting water source.

"Spring-fed wells provide all water usage, including a dedicated tank for the fire hydrant and sprinkler system," the studio said. "The concrete basin captures water after it is harnessed by a Pelton wheel for supplementary hydroelectric power, offering a continually refreshed basin for cooling dips."

Designing around fire risks and the celebration of water are constant elements in Faulkner Architect's practice.

The studio recently centred a Nevada house around a large water basin and used noncombustible materials for a Lake Tahoe cabin.

The photography is by Joe Fletcher.

Project credits:

Faulkner Architects design team: Greg Faulkner, Jag Kievenaar, Jenna Shropshire,Owen Wright, Daniel Thompson, Lesa Faulkner, Chris Carbajal, David Regina, Kirt Hilker Architecture and interior design: Faulkner Architects Contractor: Annadel Builders, INC Civil engineer: Summit Engineering Structural engineer: Strandberg Engineering Mechanical engineer: Sugarpine Engineering Electrical engineer: Sugarpine Engineering Geotechnical engineer: RGH Consultants Landscape: Terremoto Lighting: O-Lighting Surveyor: Munselle Civil Engineering CALGreen: Soldata Energy Consulting