SEATTLE — Jeff and Steve really went the extra mile, energy-efficiency-wise, in their search for a brand-new forever home: They didn’t drive a single extra mile.

Considerately, and sustainably, the perfect net-zero possibility beckoned from a website with a decidedly eco-friendly outlook.

The couple has lived in Seattle since 1997, says Steve — first in a 1920 Dutch Colonial that “was never quite warm all winter,” and then in a Mount Baker home by green pioneers Dwell Development.

“We liked those features and design — it was sturdy,” says Jeff. “We were checking the Dwell site regularly.”

Things started clicking. And now, Jeff and Steve’s dazzling new Dwell dwelling checks every forward-looking forever box:

— It’s on a particularly scenic site in a particularly familiar neighborhood: Mount Baker. “We just kind of knew this area,” Steve says. “On summer days, when they close Lake Washington Boulevard, it’s nice to have it right there.”

— It’s super-sturdy. “I’ve had cars that aren’t great cars,” says Steve. “Having lived here six months, I just feel it’s solid. You’re cruising instead of bouncing along.”

— It’s roomy, airy and light, with 3,700 square feet, five bedrooms and four bathrooms. “One of the biggest attractions is the space, the openness front to back,” says Steve. “We’ve entertained more here in six months than the five years in our old house.”

— It’s strikingly modern — another Dwell hallmark, says principal Anthony Maschmedt. “It’s low-maintenance interior design,” he says. (Abbey Maschmedt of Dwell was the home’s interior designer; Jeff and Steve also worked with Jill Rerucha of ReruchaStudio after they moved in.) “No statements were made with color; they make their own: wood, reclaimed materials, a chevron island, Carrara marble. We try to be very, very neutral and use the same themes: metal, glass, concrete.”

— And it’s greener than the sprawling swath of park just across the street — innovatively so. “It’s the first Built Green net-zero home certified in Seattle,” says Maschmedt. “We used low-maintenance materials, no chemicals, no VOC. There’s no smell, no off-gas, and all water-saving fixtures and low-flow toilets. When we get an average year, it’ll blow the socks off the model.”

In the meantime of that first moving-date milestone, there’s a whole lot of above-average energy-efficiency going on up high — just beyond a clever cutout on the top level of the two-level boxy deck (stabilized by a mesmerizing cable X), and even higher.

“We have the maximum amount of solar panels on the (lower) roof,” Maschmedt says — but not quite enough to achieve net-zero. “We got right to the end and had an energy rating of 1. We don’t want 1. That’s not good enough. We popped on three more panels on the higher part. You don’t want to run a marathon and stop at 100 yards.”

Sharing rooftop real estate with 11kW of photovoltaic panels is a cool-on-many-levels solar hot-water system that transfers heat through thermal gel instead of water. “That water technology had flaws,” Maschmedt says: “On hot days, tubes on the roof would overheat. On cool days, the water would freeze. Here, Silk Road Environmental fluid runs through the tubes and holds the heat. It’s a beautiful thing. It can get up to 700 degrees before it’ll overheat, and down to -50 before it freezes.”

Lower to the ground, a flexible, free-flowing floor plan stretches up three levels, and all the way back to a covered outdoor entertainment area. Along the way: a happy-surprise indoor rock garden under the first flight of stairs; a packed “control room” that holds the home’s high-tech systems; and, instead of a butler’s closet, Maschmedt says: “a bartender’s closet.” (“That’s one of Jeff’s favorite rooms: where we keep the wine,” Steve says.)

Jeff and Steve are independent consultants who both work from home: Jeff in a spacious main-level office (behind a jumbo sliding barn door made of sustainably harvested oak from Montana) that could adapt to a full mother-in-law suite, and Steve on the tippy-top third floor, anchored by a special piece of artwork by their Phoenix friend Rocco Menaguale, and enhanced by a calming view of the familiar neighborhood.

“It was our intention to watch people walk by in the park,” Steve says. (They can do that from the shower in the master suite, even, thanks to a strategically placed horizontal window.)

Passers-by are watching back.

“We had people stop and ask to take pictures of the house,” Steve says. “They’re interested to see the solar panels: ‘Tell us about that.’ ‘How does that work?’ People have stopped about the (solar thermal) tubes: ‘What’s that?’”

Jeff and Steve are more than willing to pass along what they’ve learned on their low-mileage journey to this supremely green home.

“The Dwell team is so wonderful about educating us,” Jeff says. “Sustainability is part of the overall savings — over the long haul, it will decrease the cost. Another practical perspective: We have a more-healthy environment, with clean-air systems and airtightness. We’re focusing on environmental issues: climate issues, not dumping waste or pollutants, natural materials. We want to know what we need to do. This is where we spend our time.”