The challenge: build the greenest houses on earth—and make them affordable.
posted May 25, 2012
The notion of building or remodeling to deep green standards is daunting. A 2011 survey by the National Association of Homebuilders found that 60 percent of professional builders thought environmentally sensitive housing was too expensive for low-income people and 30 percent said even the middle class couldn’t afford it. But modern pioneers—from owner-builders in British Columbia to designers challenging the harsh conditions of the Aleutian Islands—are showing that green building on a budget, even to the most exacting standards, is possible with enough creativity and planning.
In a Family Way
Ann and Gord Baird hand built what Jason McLennan, who developed the Living Building Challenge (LBC), has called “the greenest modern house in the world.” The LBC is the most far-reaching green-building program in existence. It requires, among other things, that a building use only the water and energy available on the site, use materials responsibly, and be healthy and beautiful. The Bairds met most of the requirements of the LBC, and they did it themselves on a tight budget.
But they didn’t do it alone. Ann and Gord pooled their resources with Ann’s parents to buy the land in Victoria, British Columbia, and build a durable 2,100 square foot house with two semi-independent residences. The Bairds and their two kids live in one and Ann’s parents are in the other. They save costs by sharing the heating, plumbing, and electrical equipment along with the phone, freezer, and washing machine, while still maintaining most of the autonomy of a single-family home, including two separate kitchens with a pass-through between them.
The Baird residence is the first permitted load-bearing cob structure in North America. Cob is a mix of straw and earthen materials, similar to adobe. “Mud is pretty cheap,” says Ann, and the cob construction naturally regulates the humidity and temperature of the house. In an area where the average cost of a low-end conventional house is $190 to $250 per square foot, the Baird’s house cost $148 per square foot, including solar PV and hot water systems and a reasonable price for Ann and Gord’s labor.
In addition to inexpensive cob construction, and shared walls and equipment, they went with used materials when they could. Addressing another aspect of the LBC, the Bairds estimate they use about 40 liters of water per person per day versus the average B.C. usage of 490. They use composting toilets and low-flow fixtures, irrigate their food gardens from a 10,000-gallon rainwater harvesting system, and use gray water from the house to irrigate their fruit and nut trees.
These are just a few of the home’s sustainable and resilient features. The Bairds make a point of showing it’s not how green you make a house, but how effective, that determines affordability. “We use ninety percent less electricity than the average person in B.C.—and that’s about lifestyle choices,” Ann says.
A Contest for a Challenging Location
Public housing authorities are notoriously conservative about using scarce funding for something as experimental as green building. Until there are proven projects that show what’s possible, most funding agencies don’t want to take chances.
The Aleutian Design Competition, a joint project of the Aleutian Housing Authority and the International Living Futures Institute (ILFI), called for designs for single-family homes in Alaska’s remote Aleutian Islands that not only meet LBC, but are also affordable and replicable. The housing authority will build the house that wins the challenge.
While on average it’s not the coldest place in Alaska, driving wind, rain, and snow are common in the Aleutians, along with incredible cold snaps. In the lower 48, green homes take advantage of winter sun through passive solar design. In a place with almost no winter sun, that’s just not an option.
Despite the difficulties, 47 designs out of 104 complete submissions were selected as likely to meet the LBC challenge, with an incredible range of styles and strategies. Designs included everything from the mostly subterranean traditional Aleut barabara structures, to space-age designs, traditional ranch homes, and modified shipping containers. Insulation materials ranged from high tech to local rye grass. There is no single way to design a living building.
“Finnesko,” the winning design by a team of three young architects from Madrid, Spain, was a reinterpretation of the classic Quonset hut, a form that McLennan says appears in remote locations because it is easy and repeatable.
The designs that did the best emphasized simplicity and ease of construction, with a lot of flexibility in details. All of that contributes to affordability. If the Housing Authority learns a particular detail doesn’t hold up in the climate or is too expensive, they can try another option. The competition allowed the Aleutian Housing Authority to learn from all the best ideas, and provided a wealth of design strategies and details to work with as they move forward.
A Phased Approach
Saving energy is a key consideration for any organization focused on affordable housing. “We’re facing stagnant revenues along with increasing utilities and operation costs,” explained Ben Gates of Central City Concern (CCC), a nonprofit in Portland, Ore., that helps people affected by homelessness, poverty, and addictions to achieve self-sufficiency. CCC is on a tight budget, but the possibility of dramatic reductions in operating costs inspired the group to aim high. According to Gates, it’s big ambitious goal-setting like LBC that supports big accomplishments—even if the goal isn’t fully reached, or is achieved over time.
CCC is rehabbing a turn-of-the-century 160-unit apartment building in Portland to “Passive House” standards. Like the LBC, Passive House takes green design to the extreme, but focuses only on energy. Passive House design can reduce heating-energy use by 90 percent through a virtually airtight, superinsulated building that relies almost entirely on the sun and occupants to keep the building warm.
CCC doesn’t have the funds to do a full retrofit all at once, so they’re taking a phased approach. They emphasized efficiency during the design phase, and they’re building in key improvements as they rehab various parts of the structure. “Normally you wouldn’t put triple-paned windows in a poorly insulated structure,” Gates says, “but the next phase will have an exterior insulation wrap.”
“As an institutional owner, we’re likely to have these buildings for another 100 years,” Gates says. Typically rehabs happen every 15 to 20 years. “Everyone has to rehab—you always have components that are aging out, so as long as we’re spending money on rehab that’s along the lines of what other affordable housing agencies are doing, we can make the argument that it’s a good use of funds.” For example, by investing in windows that will last 50 years, instead of replacing a low-cost window in 20 years, they can focus on other things in the next rehab cycle.
Rebuild at Home
A phased approach is helpful for single-family homes too. While McLennan has sparked a revolution through the LBC, in his home life he’s not all that different from many other homeowners. “I’m typical of a person who doesn’t have a lot of time nor huge buckets of money to throw at my house, and I bought an existing house.” He takes his time, but the LBC framework informs everything he does. “Every year I do a small project. Sometimes it’s just ensuring the investment in materials is respected—making sure the house doesn’t leak.”
McLennan’s house was built out of all salvaged materials in the ’70s, and he is continuing that legacy of reuse and adaptation. It can be as straightforward as taking the shingles off the exterior wall where McLennan was building an addition and using them on the new wall.
One of the trickiest parts of the challenge for professional architects is avoiding the hazardous chemicals on LBC’s list, but that doesn’t stop McLennan. “I’m pretty darn strict about what chemicals I bring into my house,” he said. Still, that can mean Ikea’s low cost furniture, since the company has relatively rigorous policies about hazardous materials, rather than premium priced options. “Like everyone else I just do the best I can.”
Changing the game
The story isn’t just about what people can do now; it’s about making way for others.
“Our real goal with the LBC is not to certify buildings, but to actually change the market so doing the right thing is the natural course of business,” says McLennan. And that’s starting to happen. It’s also the changes quietly and not so quietly being introduced into the codes that define what people can and cannot build that make things easier for the rest of us. “It will never be more expensive than the first living building,” says McLennan, because those first buildings are creating the templates for a new approach and teaching others.
If these pioneers are making living buildings on a budget, the rest of us can too.
Jennifer Atlee wrote this article for Making it Home, the Summer 2012 issue of YES! Magazine. Jennifer is a researcher, writer, gardener, and engineer. Research director for BuildingGreen, she has focused on system-wide sustainability since she thru-hiked the Appalachian Trail at 18.
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YES! Magazine encourages you to make free use of this article by taking these easy steps. This work is licensed under a Creative Commons License
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