For 10 years, Diane and Paul Jacobson had the perfect vacation arrangement — sharing a house on Lake Superior with seven other couples, which allowed them to share costs, maintenance and ownership responsibility. "The house overlooked the lake," said Diane. "We loved to walk down to the rocky shoreline."

But when the Jacobsons approached retirement, six weeks a year and ⅛ ownership didn't seem like enough time in the North Woods. "We wanted our own place all year-round, to have our kids, grandchildren and friends over," said Diane. "We wanted it to be a gathering spot."

For their own retreat, the St. Paul couple hunted for property in the same area, which was near the quaint town of Grand Marais, albeit on a lake much smaller than Superior.

In 2007, they decided to investigate a 2-acre parcel nestled next to the Superior National Forest. "It was winter, and we had to hike a half-mile from our car," recalled Diane. The densely forested site was covered with white pines and birch and was on a small secluded lake connected to several other lakes where they could fish, swim and canoe. "We loved that it was surrounded by a national forest, and isolated but still close to Grand Marais," she said.

They bought the land and embarked on the challenging process of building a home for the first time in their lives.

The couple enrolled in a University of Minnesota Compleat Scholar class on home construction led by SALA Architects, a Minneapolis firm. The Jacobsons had seen photos of works by SALA architect David O'Brien Wagner at the Lake Home and Cabin Show, and asked him to come to the last day of class.

They showed Wagner a floor plan they had drawn, which included many of their must-have features and reflected their desire for minimal environmental impact. That resonated with Wagner. "I design with sustainability in mind," he said. "It was clear we were on the same wavelength from a design and sustainability standpoint. It was a good match."

Towering design

Wagner visited the northern Minnesota property and discovered several siting challenges. It was a steep hillside of dense woods and included a flowing stream. Plus the Jacobsons wanted to save a 200-year-old cedar tree standing on a level area near the lakeshore. And where would they drive up and park their car?

Wagner's solution was an innovative 50-foot-long footbridge, built over a stream, that connected a separate parking area to the home's front entry. The bridge's cable railing gives it a lightweight quality and makes it disappear into the wooded setting. "Metaphorically you cross the bridge into a new realm — the woods — and leave your everyday world behind," said Wagner.

Wagner's design met many of the couple's requirements, including the flexibility to open up the home when their extended family is staying over but close it down to create an intimate feeling when it's just the two of them.

The home is essentially a grouping of simple boxes wrapped around the precious cedar. The boxes provide function as well as minimizing the scale of the 3,200-square-foot home. "With separate pieces, no one piece is too large," said Wagner. "It also helps the building weave its way into the forest seamlessly."

The Jacobsons also got the lookout tower they've always wanted. "We asked David for a tower where we could look out at nature from all angles," said Paul. So Wagner incorporated a four-story tower into the design that houses the front entry and staircase.

At the top is an aerie — which serves as Diane's office as well as a contemplation spot with a 360-degree panoramic view of the lake and treetops. "It's a charming room — we have coffee up there," said Diane. "It feels just like a fire tower."

In fact, it was inspired by Wagner's childhood. "I grew up in the Cascade Mountains, and would visit forest lookout towers," he said.

A hallway in the tower leads to the center box holding the kitchen, dining room, great room and bathroom. A wood-burning stove warms the open spaces surrounded by a two-story bank of windows opening to the woods and lake beyond. Up on the second floor is the owners' bedroom and bathroom. A loft overlooks the great room on the inside, and windows give views of the forest and lake.

The loft is where Paul, a flutist for the Lyra Baroque Orchestra, often practices. The spaces have excellent acoustics, thanks to high ceilings, Douglas fir paneling, slate floors and very little upholstery. "The home has a delicious warm and resonant sound," he said.

Family members and friends can sleep in the two bedrooms in the guest wing, which can be closed and unheated when not in use.

The Jacobson home's "wow" feature is its high ceilings defined by exposed fir beams and industrial-looking web trusses of wood and steel tubes. "It's a structure you might find in a warehouse or factory," said Wagner. "It's expressive."

The Jacobsons are both handy and like to be able to see how something is constructed, they said. "The open trusses look architecturally fascinating, not unfinished," said Diane. "Our friends call it modern industrial chic."

On the exterior, Wagner clad the home in fireproof corrugated zinc in a "soft gray muted color," he said. Zinc can last more than 100 years, although it's pricier than other siding materials. "It ties into the industrial character of the mining buildings up the North Shore," said Wagner. "Corrugated metal siding, simple box forms and open trusswork all hearken to that straightforward design aesthetic."

Green-minded

The Jacobsons were committed to building an eco-friendly dwelling using sustainable strategies, such as photovoltaic solar panels and geothermal heating, to make it as energy-efficient as possible. "We wanted to be close to nature, but not harm it," said Diane.

They take a long-term view of the geothermal heating's upfront costs, which Paul estimates will be paid back in 10 years with savings in energy bills. And then the home will consume less energy for decades when they pass it down to the next generation. "Geothermal heating with radiant in-floor heat is a proven technology," he said. "It costs 30 percent less to heat in the winter than our old farmhouse in St. Paul."

Now that they have their very own wilderness retreat, the Jacobsons head Up North whenever they can — not minding the five-hour drive from St. Paul.

The glass-walled aerie is where Diane, a retired professor, spends most of her time writing on her laptop. "There's something about being in the middle of nature surrounded by loons that helps you think and communicate more clearly," she said.

Lynn Underwood • 612-673-7619