When Scott Shell moved to Marin County in 2007, his house came with a 48-inch Viking range. The current version of the eight-burner, two-oven, professional-grade appliance, which retails for around $13,000, lets you impress foodie neighbors with how fast you can char shishito peppers with 15,000 BTUs. But in recent years, the 59-year-old architect has felt nothing but disdain for it.
“It’s like cooking with coal. It looks hopelessly old and clunky, and it’s polluting the air inside our home,” he says, referring to nitrogen dioxide, a toxic gas produced at often unhealthy levels by open gas flames. “I want an induction cooktop, which has a glass top like an iPhone, for a really modern kitchen.” He is also drawn to induction cooking, which uses electromagnetism for heating, because it reduces fossil fuel use and is more efficient and faster.
Alta Live welcomes Susan Jones of Atelier Jones, EHDD’s Scott Shell and Alta Journal contributor Lydia Lee on Wednesday, June 2 at 12:30 p.m. Pacific time.
Shell has been designing all-electric, energy-efficient buildings at the venerable San Francisco firm EHDD for the past 20 years. He champions this approach both for better modern living and to combat the existential threat of our times: climate change. It may come as a surprise, but constructing and powering buildings actually generates the largest percentage of the world’s energy-related carbon emissions, outstripping the transportation sector. Decarbonizing buildings is one of the easiest and most cost-effective ways of slowing climate change, which has only been speeding up. In the United States last year, natural disasters that can be attributed to warming global temperatures caused $95 billion in damage—including $16 billion due to West Coast wildfires—double the amount of the previous year.
Meanwhile, the U.S. home-building industry is by nature conservative and slow to change. “Buildings in the U.S. are among the most profoundly laggard in technology compared to other technologies we encounter,” says Kristof Irwin, a building science consultant and the principal of Positive Energy in Austin, Texas. “As a society, we’ve asked our builders, ‘How fast and how cheap can you build this? Anything that is behind the walls, I don’t care about it.’ The improvements available to homes are profound.”
In California, where raging infernos have become a yearly tradition, some architects and policy makers are racing to make these radical home improvements.
Andrew McAllister, who helps define state policy at the California Energy Commission and is the lead CEC commissioner for residential decarbonization, is setting the pace at home. His house in Davis, along with some 100 others in California, is designed using a method that was developed for frigid climes but is equally helpful for withstanding heat waves.
In the 1970s, which saw both the rise of the polyester pantsuit and the oil crisis, architects in snowy Illinois and Saskatchewan developed designs for a superinsulated house. Later, German physicist Wolfgang Feist and others refined the idea into Passivhaus (or Passive House), the gold standard of home energy efficiency. (“Passive” is a wonky way to underscore that the design is fundamentally efficient, because it doesn’t rely on “active” mechanical systems.)
The basic idea: Seal a house up and wrap it in a thick, puffy jacket, then add a ventilation system. In a brilliant stroke of engineering, the ventilation unit also captures the heat or cold from air that it exhausts, using it to condition incoming air. The whole setup allows the HVAC system to do as little as possible while maintaining an even temperature and circulating lots of fresh, filtered air. Passive Houses minimize their demand on the environment while protecting their inhabitants from the extreme temperatures that our energy profligacy is causing.
Wrapping a house in a puffy jacket might seem like a hard sell in balmy Los Angeles, but a house in the Atwater Village neighborhood shows the potential of the approach. In 2012, 52-year-old entrepreneur Xavier Gaucher “saw the light” when he learned about the Passive House certification program. “We had built our dream house in France a few years before, and everything we missed was a huge frustration,” says Gaucher, who decided to embark on a new career as a Passive House consultant. “I really couldn’t understand why we would build any other way.” In 2017, he renovated a one-story bungalow for his family, retaining the existing concrete foundation and adding a second floor. The 2,100-square-foot home uses electricity for heating and cooling, hot water, and all appliances. And it has no electricity bills, thanks to solar power. The house is very quiet despite traffic on Interstate 5 half a mile away, frequent helicopters overhead, and Amtrak trains zooming nearby. And the ventilation system keeps the indoor environment clear during wildfires, like the one that broke out in neighboring Griffith Park in 2018. “We were hosting an event with 20 people inside, and nobody could smell any smoke,” says Gaucher.
Even in mild California, heating air and water accounts for about half of a home’s energy use. While we’re used to gas-fired furnaces and boilers, a heat pump can heat air (or water) very efficiently using electricity. It extracts warmth from outside your house and uses it to heat indoor air—and reverses the process for cooling, eliminating the need for a separate air conditioner. “It’s a wonderfully efficient system that takes freely available energy from the air around the house and uses it for heating,” says Irwin, who is an engineer by training. “From an engineering point of view, it makes no sense to use gas to heat water, food, or air in the house. You want to save that highly concentrated fuel for your grandkid’s welding project.” In Gaucher’s home, the heat-pump water heater also pulls warmth out of the basement, allowing the unconditioned space to serve as a wine cellar.
While Gaucher’s house was designed to capture natural light and views of Griffith Park, the size and location of the windows had to be carefully considered, since glass has the least amount of insulation. Passive House is an important mind shift for architects, says Gaucher, citing the influential 1960 Stahl House—better known as Case Study House No. 22—which peers out over L.A. through its transparent walls. “It is what every architect dreams to design, but the place is miserable in terms of comfort—you’re cold in the winter and warm in the summer,” he says.
California’s energy-efficiency requirements for buildings are the most aggressive in the country, and the state was the first to mandate solar panels on new homes to supply a portion of their electricity. But Gaucher’s house is still 64 percent more efficient than a house built to code. A modestly sized solar array powers everything inside and the family’s main car, a Fiat 500e. Over the course of the year, the solar panels produce slightly more energy than both the home and the vehicle use, a net gain that goes back to the electrical grid. Naturally, the more efficient a home is to begin with, the easier it is to get to net-zero, an objective that aligns with the state’s overall goal of carbon neutrality by 2045.
Abolishing natural gas is also happening faster in California than anywhere else. Just over 40 cities have passed restrictions or incentives against using natural gas as a building fuel source, and state legislation may not be far behind. Natural gas is not the worst fossil fuel to burn, but it is still a major contributor to global warming. About 10 percent of California’s greenhouse gas emissions come from using natural gas in buildings. And if all homes in the state were to go all-electric, hundreds of deaths and cases of acute and chronic bronchitis could be avoided, according to the California Air Resources Board.
Into the Woods
Given the imperative to cut carbon emissions drastically and immediately, architects are also looking for “low carbon” building materials. By one estimate, producing construction materials accounts for more than 10 percent of global carbon emissions. The trifecta of modern architecture is steel, glass, and concrete—architect Pierre Koenig notably relied on them for the Stahl House. Alas, steel and concrete both take enormous amounts of energy to produce. Trees, on the other hand, sequester carbon, removing it from the atmosphere and locking it away in their wood. Mass timber—engineered lumber composed of many thin pieces of wood—is strong enough to replace concrete and steel.
The garden-variety house already has a wood skeleton, which is covered in siding on the outside and drywall on the inside. But architect Susan Jones built her dream house in Seattle almost entirely out of solid wood—giant pieces of cross-laminated timber, or CLT. It’s a type of mass timber made from layers of wood that are stacked crosswise for greater strength. “Growing up in the Pacific Northwest, I am part of this incredible natural environment,” she says. “I thought, How can I make anything more beautiful than a tree?” Several inches thick, the CLT panels were cut to size at the lumber factory and craned into place. Jones applied a light whitewash to the raw wood surface, leaving it otherwise unfinished. “You can see the knots and the grain pattern of the wood—you have a really visceral sense of the trees and all their life contained in that panel,” says Jones.
Down in Napa Valley, architect Brandon Jørgensen, who is replacing several homes lost to the fires in the area, hopes to use CLT for his next rebuild. While it sounds counterintuitive to build with wood in fire-prone areas, mass timber is extremely fire-resistant. “Homeowners get the coziness of wood, and just the efficiency of CLT is attractive,” says Jørgensen. “It integrates structure and finish, and the prefab pieces give you ease and speed of construction—it’s light-years ahead of a normal stick-built house.”
Designing a house to resist fire is more involved than just avoiding wood shingles. Jørgensen uses exterior materials such as metal siding, metal roofing, and fire-resistant ceramic glass. But he also tightly seals his homes, minimizes air vents, and customizes the vents that are necessary. As it turns out, most buildings that are lost to fire are not engulfed by a roaring flame. Rather, they fall victim to burning embers that could be blown from a fire that is miles away and land on roofs, in air vents for attics and crawl spaces, and in cracks around doors and other gaps. “In the Tubbs Fire, those new tract homes in Santa Rosa burned from the inside out,” says Jørgensen. “They had fire-rated exteriors, but they burned mainly due to ember penetration.” In the most fire-prone areas, a five-foot “ember-resistant zone” around each house is now required by California law, although the specific details of that zone still need to be worked out. White quartz mulch may be coming back into style soon.
How much more does it cost to build a house that mitigates climate change? According to Gaucher, who used standard materials such as wood framing and fiberglass insulation, renovating the home to Passive House standards added only 3 percent in construction costs. “It’s mostly about paying attention to the construction details and having an extremely detailed set of architectural drawings, so that decisions aren’t left to the construction phase,” he says.
The real potential to deliver energy-efficient, cost-competitive homes lies in prefab construction—houses that are built in a factory and delivered to a site. Architect Le Corbusier’s famous 1923 manifesto, “Towards a New Architecture,” championed a new aesthetic for homes based on functionality and modern construction. “A house is a machine for living in,” he wrote. “So he might add, these days, that homes should be made by machines,” says Steve Glenn of Southern California–based Plant Prefab. According to Glenn, prefab can cost up to 25 percent less than a custom home built on-site, in addition to cutting the time needed for construction. The company, which got its start in 2006, announced its first three Passive House models at the end of January.
The home of the future may show up soon in a backyard near you. To address its housing crisis, California passed legislation to encourage people to build guesthouses (a.k.a. accessory dwelling units, or ADUs), increasing the housing density of the suburbs. Vu-Bang Nguyen, a 40-year-old city planning consultant, is living in a one-bedroom unit that he purchased at the end of 2019 and that was craned into his parents’ backyard in San Jose just six months later. Made by Bay Area–based Abodu, his home is wood-framed, heavily insulated, all-electric, and designed to be net-zero. “I wouldn’t be able to afford the level of architecture or this level of build that this has provided me,” Nguyen says.
Like many of us, Shell in Marin has been cooking a lot during the pandemic. One of his favorite dishes is bay scallops seared with a little butter and lemon. But instead of turning on his Viking range, he uses a portable induction burner that sits on the countertop. To avoid having to remodel his kitchen, he’s waiting for a manufacturer to make a 48-inch induction range. And then that Viking will be outta there. Says Shell: “I’m so ready, I can’t wait.” •