Lake Effect: A Minnesota Cabin Renovation Creates an Earth-Friendly Home

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Photography By Terrence Moore
The artwork above the tub is cut Inuit stone. Artist Diane Daniels made the mirror and frame. The bathroom counter, as in the kitchen, is made from local Lake Superior Greenstone.

By the time Medora Woods had reached the end of the dirt road, she was in love. Winding through nearly six acres of birch and pine forest, the road ended at a simple 1947 cabin nestled on a wooded point overlooking the rock-lined Lake Superior coast near Tofte, Minnesota. In 1997, the former lawyer and Jungian analyst bought the property knowing she wanted to renovate the cabin for year-round use–but without the materials waste, energy consumption, and site destruction such projects usually generate.

“Let’s build an earth-friendly house,” Medora told her architect, Sarah Nettleton. The two then launched into a design and construction process devoted to figuring out what that meant.

Medora wanted the site to dictate the building’s size, materials, and design. She wanted energy needs fueled via renewable sources. She was willing to explore and incorporate untried sustainable design technologies. At the same time, she wanted to render visible the invisible connections between a product and the natural species and systems that make its manufacture possible.

In essence, Medora wanted a cabin that demonstrates what it means to build lightly on the land. “From the beginning,” she says, “Sarah and I understood ourselves to be in a transformative learning process about what sustainable design is and means. There is no sustainable design manual with lists of available products and technologies. Every question leads to a dozen more. There is ongoing tension between having a grand idea and making it practical, between wanting to be responsible for the impact of the project on the present and on the future.”

The 960-square-foot cabin is a physical manifestation of such complex and interrelated factors as the site’s ecological and cultural history, Medora’s needs and beliefs, and an architect and client’s trailblazing approach to sustainable design. In 2001 it won an AIA Minnesota Honor Award. In 2002, the American Institute of Architects’ National Committee on the Environment named the cabin one of the Top Ten Green Projects. Because the cabin is considered a demonstration project for sustainable building in a cold climate, Medora and Nettleton recently completed a website that walks visitors through all aspects of the project’s construction and design.

Beyond greenwash

Since she retired, Medora–a self-described “roving, troublemaking grandmother”–has been exploring a twenty-year fascination with Native American culture as well as Americans’ increasing psychic and physical disconnection from place. “I became interested in indigenous cultures because to me they represent another way of being in the world,” she explains. “From them, we can learn how to undo some of the tremendous damage on the planet.

“If you’re part of an earth-based culture,” she continues, “you know where everything you use comes from. You have a relationship with the living being–a tree, a plant, an animal–that sacrificed itself in order for you to have something; you have a relationship with the entire ecosystem you’re in. And, you respect all the other beings and spirits that inhabit your dwelling place.”

So, one might ask, why build anything at all? Why not live, as many indigenous cultures have, in a tipi or earth shelter? Medora laughs and replies, “Because I chose not to live in a tent! And having made that decision, I had to make choices about materials, heating, and cooling. With sustainable design, you begin to align yourself with natural forces instead of fighting against them. The wind blows, the sun shines, the earth warms or cools–and you take advantage of it.”

Medora and Nettleton started by retaining the modest footprint and floor plan of the original cabin, extending by a mere 3 percent to 960 square feet. The windows are mostly the same size as the originals, or in the same place. The architect took off the roof, turned it, and raised and curved the ceiling so maximum sunlight warms and illuminates the cabin in winter and the sun’s hot rays are minimized in summer. In addition, operable clerestory windows admit light, which in turn passes through glass borrow lights between the curved ceiling and tops of the bedroom walls. “Throughout the day, light washes across the ceilings and walls and winds down the curved roof,” Nettleton explains. “The interior of the building is like a sundial connecting to points on the horizon where the sun rises and falls.”

The cabin’s simple palette of materials, most of them recycled, also creates a seamless aesthetic that joins site and cabin. The interior of the roof’s curve, clad in recycled pine lap siding, provides intimacy while recalling the underside of a wooden boat hull–the type of boats that once plied the waters visible through the cabin’s picture windows. The pine used throughout the cabin came from the Menominee nation’s sustainable forest in Wisconsin, was recycled from a local building, was salvaged from the bottom of Lake Superior, or was ordered from a certified sustainable plywood mill in Oregon.

Scrap lumber from the roof decking was reused in casework. To replenish board feet used, Medora replanted an equivalent number of trees. “There’s not a lot inside that’s arguing with what’s outside,” Nettleton says. “That’s huge in terms of a sustainable design aesthetic: manifesting a connection to place through materials.”

Making the connection

Design, like the boat hull ceiling, enhances the connection as well. The horizon line of the lake and the sky, for instance, is repeated in the deck’s ship-deck railings, the tile surround for the bathtub (which also features tiles imprinted with the shapes of Lake Superior fish), and the kitchen’s local granite countertops and backsplash (the color of which mimics the spruce, the lake, and the lakeshore).

Energy use, naturally, has a tremendous influence on a building’s ecological impact. “The first criteria of a green energy strategy is to reduce the load,” Nettleton says. Daylighting, extruded rigid insulation (free of ozone-depleting chemicals) to decrease heat loss, and a low-energy refrigerator and washer/dryer minimize the cabin’s energy use. Photovoltaic panels installed on the garage roof (functioning as shingles) and a wind-powered generator create the small amount of energy the cabin uses. A geothermal (or ground-source) heat pump supplies warm water for the cabin’s in-floor heating system.

“Our goal was to zero-out the energy use on an annual basis,” Nettleton says. “That is, generate as much energy as the cabin uses, so there’s no load on the local electrical grid.” In fact, the cabin occasionally gives excess power back to the grid.

In addition, nearly 95 percent of the construction waste was recycled. The roof insulation was cut to size by the manufacturer to decrease jobsite waste and trucking costs. The copper roof, with high recycled content, eliminates batches of asphalt shingles that would end up in landfills in the future. Low- or no-VOC paints were used to finish the exterior and interiors.

Care was also taken with the site’s natural communities. In areas where construction occurred, the excavator cut the vegetation and pushed plant material and soil to the side, and later spread this seeded topsoil over disturbed areas. The geothermal well field was replanted with native shrubs. Last, to fully integrate mind, body, and soul into the cabin, feng shui principles guided interior design and the placement of the deck stairs.

Bringing shadow to light

The project was not without its shadow sides. “I’m not opposed to technology,” Medora says. “We have little choice but to find technologies that allow us to live, unless we all go back to subsistence living–which is entirely possible but won’t be of our own choosing. If you follow each technology to its source, however, it often bites back.”

Products or materials might read “green” according to a manufacturer’s information. But if they’re made in Oregon, what’s the ecological impact of transporting them to Minnesota? What toxins might have been produced during the product’s manufacture? Are the right people available locally to install it? “Products are shipped vast distances to distributors and then to construction sites,” Medora explains. “No one at the site or in the architect’s office has firsthand experience of how that product is made, and the customer is not interested in finding out.” The materials and construction systems in the United States, Medora says, “keep this information invisible. Now that I know about all of these connections, I can’t render them invisible to myself anymore.”

Knowing that conventional plywood is toxic to make, Medora and Nettleton found sustainable plywood from Oregon (no longer available). “We were planning to use windows being manufactured by a well known and respected local company,” Medora says. “I happened to read in The Circle, the local native newspaper, that the company was having labor problems, that a Native American employee was complaining of discriminatory treatment. Knowing there were probably two sides to that story, we still elected not to use this particular manufacturer for that reason, even though our policy was to buy locally whenever possible.”

The closest lumber from a sustainably managed forest is produced by the Monominee tribe in Wisconsin. “To buy it, again, meant not following our priority of buying materials that originated as close to the building site as possible,” Medora says. “It also meant problems for our construction schedule as we were buying less than a full load, so we had difficulty getting it to the site in a timely manner.”

Because roofing material accounts for a large amount of the material in landfills, Medora and Nettleton chose copper, which has a long, useful life and can be recycled. For the garage roof, they found Eco Shakes, a product made by an Oklahoma company that guarantees a fifty-year lifespan and will take it back and recycle it after its useful life is over. “Unfortunately, an Oklahoma product requires substantial transportation–in this case, by truck–which has fuel consumption and emissions consequences,” Medora points out. “By ordering the product through a local distributor, we hoped that the increase in volume would mean the product could at least come by rail in the future. Although we succeeded, our distributor subsequently went out of business.”

The problem, Nettleton says, was that the infrastructure was not in place to support sustainable design in their area. “Because of Medora’s willingness to commit to her ideas about design and construction, she supported our deep look at reinventing the process of sustainable design,” she adds.

Medora delights in a cabin that offers her quiet, solitude, and a link to place. “I love knowing all the ways this cabin and the process of creating it have embodied a sense of connection to something larger than myself,” she says.

“I was determined that my cabin renovation would be more than just ‘greenwash,’ ” she continues. “In this culture, 4 percent of the world’s population uses 25 percent of the world’s resources. We can’t continue with such waste knowing that war, instability, and hatred are the result. I invested in what is essentially a demonstration project for the state in sustainable building practices. I’m happy to have done something that might encourage others to live lightly on the earth.”