He carries a slide rule, but Rich Martin runs a business lodged squarely in the future.

His mission, he says, is to provide the best indoor air quality. Homeowners get sick from poor construction. He’s changing that. The 10 jobs Northern Dean does annually are always built so they’re under positive air pressure. Roofs and walls are doubled up to guarantee waterproof surfaces (no mold) and to circulate air, in part to increase time between paint jobs (lack of heat buildup protects paint). High-velocity, 2-inch ducts air condition rooms; hot water is re-circulated to sinks for energy efficiency; Martin has installed radiant heat for decades.

Such measures add 15 percent in costs. Never mind. Clients with $1 million remodels wait nine months for Northern Dean. Sixty-seven percent are repeat customers; 98 percent become friends, says Judy Martin, Martin’s wife and office manager. That’s in a community of 25,000.

If a job requires trees to be felled, they’re often cut for the project at the company mill. “People love to think they use their own trees,” Martin says.

Recent projects include a 115-foot barn-to-house tunnel/ art gallery, a 1,200-foot long rowing pond, a barn/silo conversion built around a tree. A fireplace features a second-to-first-floor waterfall.