Green House

This Oakland Hills home shows just how nice eco-living can be.

Mike McDonald doesn’t mind having strangers in his Oakland hills home. In fact, he invites architects, neighbors, and journalists on tours.

That’s because his modern two-story Margarido House, with its spectacular Bay views, is not just a private residence for him, his wife, two young daughters, and two kittens. Margarido House has become a nationally recognized demonstration project for upscale green home design, winning the highest level of certification—platinum—from the Leadership in Energy and Environmental Design (LEED) rating system. The home, built on the site of a house that was charred in the 1991 Oakland hills fire, is the first residence in Northern California to earn this distinction.

McDonald, president of McDonald Construction and Development, begins my tour at the foot of his home’s front steps. Sporting a goatee and talking energetically, he is both a prophet and salesman for green design.

He first points to the driveway. It curves up a steep slope from Margarido Drive, from which the house gets its name. The driveway is paved with plain but decorative, recycled concrete tiles that match the home’s modernist aesthetic. What’s more remarkable is that the blocks are permeable and capture storm runoff. The water feeds into a 4,000-gallon underground cistern, which irrigates all of the landscaping on the site, including the roof garden.

“We’re not using city water, and we’re capturing water that would run down the street, piling up with oils and other pollutants that would go into the creeks, and into the Bay,” McDonald says.

He then gestures to the fireproof concrete and tiles covering the exterior of the house. They come from two of the dozens of Bay Area businesses that McDonald brought in as collaborators: Concreteworks in Oakland and Heath Ceramics in Sausalito. Working with local businesses was very important to McDonald, and not just because it would be cheaper and more convenient. Such collaboration fulfilled an important principle of this green builder: to work with artisans and suppliers who could devise innovative and beautiful eco-friendly features to fit the site. McDonald tells me the tiles are old shelves used in Heath’s kilns. They would have wound up in a landfill. Instead, Heath’s co-owner, Catherine Baily, found ways to reglaze them and turn them into something unique.

“Sustainability is about so many things: conserving resources, using nature wisely in design,” says McDonald. “But it is mostly about community and working together toward our common goals.”

Other Heath kiln shelves, glazed moss green, are set into the floor of the foyer. Concrete is used for the floor of the big, bright great room—a combination living and dining room and kitchen. Natural light pours in from the tall windows and west-facing sliding glass doors, which open onto a patio and offer one of the home’s many Bay views.

McDonald invites me to take a seat at the kitchen’s island, which is topped with black walnut, while he brews espressos. But he gets sidetracked as he talks about the dual-pane windows, both in this room and throughout the rest of the house. On warm days, the windows allow cross-ventilation, eliminating the need for air-conditioning. On cold days, sun streaming in the windows warms the concrete floors, which release the heat at night.

Even before I hear that the floors radiate heat, they don’t strike me as cold, probably because of their cream color and polished glow. Similarly, the rest of the room feels inviting despite the spare modern furnishings. The children’s books stacked haphazardly on the shelf next to the fireplace tell me that the couple’s young daughters clamber around the sofa and at the dining table, with its bench seating. “We’re in here about 90 percent of the time,” he says, getting back to the espressos.
McDonald acknowledges that, at 4,700 square feet—including four bedrooms and an in-law suite—the house exceeds the usual modest size for green residences. But, he and his wife, dentist Jill Martenson, wanted the space. They also figured that the larger square footage would make the house more desirable, were they to sell, and would help justify the nearly $900,000 they paid for the lot.

Proving that a big house can also be green gave McDonald and his team of designers, including his architect brothers on the East Coast, an exciting challenge. An important early decision was to carve the square footage out of the slope and hunker the house into the earth.

Keeping the house as low to the ground as possible accomplished two of McDonald’s aims. First, it helped win the neighbors’ support. The house doesn’t block views or intrude visually on the street, which is lined with more traditional-looking residences. Second, nestling the house against the earth provides natural insulation—called “passive geothermal” heating and cooling.

McDonald talks about other green features that are not immediately apparent but that amp up the home’s green credentials. They include nontoxic paints and finishes, high-efficiency appliances, and colorfully specked recycled glass countertops by Vetrazzo and Concreteworks.

Then, there is the 1,000-square-foot rooftop garden of native and other drought-tolerant plants. After finishing our coffee, we head for the garden by climbing a 60-foot hand-built aluminum and steel staircase that reminds me of a fire escape, but feels much sturdier.

Like most everything else in the house, the garden, with its grasses, cacti, and lavender, serves multiple purposes. Not only is it a great gathering place, it provides top-down insulation for this section of the house and allows you to see the rooftop solar panels. McDonald says the panels work much better than expected, providing about 75 percent of the home’s electrical needs.

What knocks me out, though, and probably everyone else, are the 360-degree views from the garden. McDonald points out all four bridges that span the Bay. The rooftop is a popular place for McDonald to end his tours.

“We’ve probably had more than a thousand people come through the house,” he says. “It’s fun to get the community excited. I like telling the story of this house and getting people fired up.” ■