Rise | We've Done the Research
Article By
Camille LeFevre
Camille LeFevre is an architecture and design writer based in the Twin Cities.
Camille LeFevre is an architecture and design writer based in the Twin Cities.
When Mela Breen and David Good moved from Colorado to the Sierra Nevada foothills of northern California where Breen had grown up, the timing was auspicious. The Great Recession (2007 to 2009) was full-blown, and finding a property they could afford was difficult. The couple eventually decided on a steep and rocky hillside with views down into a meadow about a mile from downtown Nevada City.
The site had a limited buildable footprint, seasonal drainage concerns (during rains, a stream literally runs through it), and a plethora of setback regulations. The site also had an "inviting" flat granite outcrop. "We bought it and sat on it for a decade, as we didn't have the funds to build," Breen says. Then, Fine Homebuilding came calling.
"They'd been following our work," says Breen, who is founder and principal designer of the architecture firm Atmosphere Design Build, which she owns with her husband, who is a builder and runs the construction end of the business. "They approached about whether we had any projects in the works that would highlight net-zero energy building, as California's building and energy code made a substantive change in 2020 to encourage net-zero new construction."
"I said, 'How about our house?' Even though the design was still in an early conceptual phase," Breen says.
Fine Homebuilding agreed as Atmosphere specializes in net-zero energy, low-carbon homes, and Good is a Certified Passive House consultant. "It was the nudge we needed," Breen says. "We jumped in." Their new net-zero energy, Passive House-inspired, high-performance, fire-resistant home became the 2018 FHB House. And it also exceeded the goals of the California 2020 initiative.
The home addresses the site's considerable constraints with a design that embraces the terrain—slope and stream, rocky ground, and granite slab—with singular ingenuity. At the same time, the 2,390-square-foot home celebrates and demonstrates the intersection of modern design and high performance. So much so that Breen and Good have named their home the "Good Haus" (a play on David's last name and Passivhaus).
Breen came up with two intersecting geometric volumes that connect the building with the landscape to address the site constraints. The first-floor volume is a long, south-facing rectangle that reaches toward and anchors into the granite. A deep west-facing porch protects the house from the hot summer sun. The porch also bridges the stream and links the first level's open floor plan to the landscape with an ample outdoor living space that includes a massive fireplace encased in dramatic shou sugi ban (charred wood) siding.
The second-floor volume runs perpendicular to the main living space and cantilevers to create a covered north entry. The south side's balcony cantilevers towards the adjacent oak forest, so the master bedroom feels as though it's in a treehouse. To support the house, Good constructed the home on a steel pier and beam structure with a metal pan deck (like those used in the construction of parking garages), giving the house the appearance of floating in the landscape.
Good's construction team used 2 x 6 advanced farming for the walls, a vapor open assembly (which can dry to the inside or outside), and three inches of mineral or rock wool insulation on the exterior, and five inches on the roof. "The amount of exterior insulation, Rockwool in this case, was driven by the climate," Breen says. "It's also bug resistant and fire-resistant, which is a huge concern in this fire-prone area." The cantilevered areas of the house "we're treated like an upside roof, so they have insulation on the bottom."
All of the connections between the interior and exterior structure were meticulously detailed to avoid thermal bridging. The sides of the home exposed to the sun are clad in standing-seam metal siding and roofing. Protected areas are clad in cedar cut and milled by Breen's father from his property nearby.
The couple chose triple-pane, tilt and turn, Passive House-certified doors and windows from Zola European Windows. "They're installed mid-wall," Breen explains, "meaning they're located between the exterior insulation and structural sheathing, which provides overall high window performance. Windows at mid-wall also allow for a punctured look and play off the extruded massing of the building."
The house, Breen adds, reached "0.55 ACH/50 according to the blower door test. That airtightness is a big payback in terms of energy performance." Air-tightness also means a need for mechanical ventilation, which Good Haus has in the form of an HRV. The balanced heat-recovery ventilation system provides high-quality indoor air and keeps the temperature inside the home comfortable and uniform. The HRV also provides air filtrations with a MERV 13 and HEPA filter. During the fire season, these aspects create a refuge from the smoke-filled air.
Small, ductless, energy-efficient mini-splits provide heating and cooling to different areas of the home. "Because of home's geometry," Breen says, "we have three ductless mini-splits, and it's rare that we have all three going at once."
The all-electric home also has a heat pump water heater with a tank, CO2 refrigerant, and an outdoor compressor. "The system has a global warming potential of 1, which is fantastic," Breen says. The all-electric home, which includes an induction range, is powered by a 6.5 kW roof-mounted photovoltaic system. The system also charges the family's electric car.
After two years of use, the house remains slightly net-positive in energy production. Last year, the couple added two Tesla Powerwalls as a backup system to run the well pump when the power goes out. "This is, unfortunately, becoming a frequent occurrence with 'planned power outages' that California's latest utility—PG&E—puts into effect during fire season," Breen explains.
The couple built a mechanical room into the ground in a location central to the floor plan, which allows for a stacked plumbing design and effective mechanical duct runs and piping. Greywater from the laundry is piped into landscape mulch basins or wells to irrigate trees.
Inside the home, wood for the native black-oak kitchen cabinets came from Breen's father's property; he milled the wood himself. The kitchen island is clad in Northern California Claro walnut stockpiled by Breen's father after salvaging several large walnut trees. The wide plank white-oak flooring came from a small mill in Tennessee that has sustainable practices. "We don't use exotic woods unless they're salvaged, and we go as local as possible while being conscious around our material choices," Breen says.
The couple selected tile from "companies located in California, and that's handmade by people who live here," Breen says. "We want to support manufacturers that have sustainable practices themselves and that provide local jobs and give back to their communities."
"We've been concerned about the future of the planet for a long time," Breen says. "When I went to architecture school, I felt sustainability had to be at the forefront of any work in which I was going to be involved, given that buildings consume nearly 40% of the energy in the US. I've been studying climate science for 25 years. I had hoped that by this point in time that net-zero energy, low-carbon building practices would be the norm. Sadly, that hasn't happened."
As a consequence, she continues, "we are going to have to contend with extreme weather. However, we continue to strive to design and build homes that use minimal energy, are healthy for their occupants, and are beautiful and resilient."
The Good Haus, finished in early 2019, illustrates how net-zero energy performance and conscientious modern design can result in a home that lives lightly on the land. "I'm really proud of our home's architecture and performance," Breen says. "It's so nice to never have an energy bill. And the home also allows me to bring in clients who've never experience a home that has consistent indoor temperatures and is comfortable all the time."
"I feel so privileged to have put our design philosophy into practice on our family project," she adds," and to have gotten to build my own home."
