A Lake House Is Nice. A Lake House With Mountain Views Is Even Better.

When Eric Sprunk announced his retirement as the chief operating officer at Nike in February 2020, he had no uncertainty about where he would be spending much of his time: Flathead Lake.

Mr. Sprunk, 58, and his wife Blair Sprunk, 55, had just recently finished building a seven-bedroom, nine-bathroom mountain modern style home with a boathouse, barn and guesthouse right on the shores of the crystal clear lake, framed by snow-capped mountains, about 70 miles north of Missoula, Mont., and about 11 miles outside the small town of Polson.

Then, a month later, Covid hit. All of their five adult children, ranging from 25 to 35, and their three grandchildren moved in too, with each family getting its own bedroom and bathroom.

“This house was perfect. There was enough space for everyone,” says Mr. Sprunk, who grew up in Missoula.

The Sprunks first spotted the land in 2015 while boating on Flathead Lake. Mr. Sprunk already owned a house on the other side of the lake, which he’d bought and renovated in 2004, right next to his father’s lake house, but he wanted to be in the section where he could see both Big Mountain to the north and sunsets to the west. “I didn’t want to end the day with shade on the dock,” he says.

They pulled their boat on to the beach, put the “For Sale” sign flat on its face and Mr. Sprunk called the listed real-estate agent, saying he’d pay cash for the 4-acre piece of land immediately. They ended up paying $1.17 million, then spending around $300,000 improving the lot and driveway.

After holding on to the land for three years without building, the Sprunks hired Seattle based architectural firm Cushing Terrell to design the buildings on the steeply sloped, three-tiered property. At the top, a big barn, where the family holds weddings (three of their children’s weddings so far), cost about $200,000 to build. Farther down, toward the lake, is an 1,800-square-foot, two-bedroom, two-bathroom guesthouse, which cost $700,000 to build. They put in $400,000 for the landscaping and the docks.

Hugging the shores of the lake at the bottom of the property and wrapping around a central stone patio and a lawn that slopes down to the beach and docks, is the 7,000-square-foot main house with an attached 2,300-square-foot boathouse, which cost around $4.3 million to build.

The front door to the main house is glass and opens to an entryway with a glass door on the other side, providing a panoramic view of the lake and mountains before even entering. All on one story, except for a loft over the kitchen, it is flanked by two living spaces, both pivoted at angles for views and privacy. On one end is the primary bedroom and bathroom suite, an office that the Sprunks share. On the other end is a three-bedroom, three-bathroom guest wing with its own sitting room area. (Ms. Sprunk calls it the “rehash room”—it’s where the siblings go to drink and talk among themselves.)

In between is a massive main room, with 40-foot-high foot ceilings and Douglas fir exposed beams. The open kitchen, with its dark oak cabinets and gray tiles and cabinets, is next, then a long wooden dining table surrounded by fur-covered chairs. The living area has a wide stone fireplace. The wall along the whole space that faces the lake is glass, with aluminum clad wood windows.

There’s a gray stone, black metal and dark wood hue, with pops of red, including red upholstered outdoor furniture. “They wanted to be able to know from the boat which house was theirs,” says Ronda Divers, who did the interior design. Ms. Divers says much of the focus was on making the home able to sustain large groups of people all at once, with durable fabrics and furniture, since the couple likes to entertain so much.

The first feature encountered upon entry to the main house is a bar that takes up an entire wall: the bottles line shallow shelves that are backlit and fronted by a sliding wood-slatted door. Mr. Sprunk calls it “booze as art.”

In the boathouse, each of the Sprunks has a boat on rails (a custom made wooden StanCraft for her and a black MasterCraft for him). A side room holds a bathroom stall like the kind found in high schools, replete with a basket of markers for guests to write on the walls. When it’s too cold to go out on the lake, the family plays beer pong and cornhole and holds parties in the boathouse, sometimes sitting in the boats up on the rails wearing life jackets. During Covid they created a pub crawl, with each family member setting up a different bar space on the 4-acre property.

Their annual Fourth of July party is what brings together all their local friends, out-of-town guests and children, who live in Portland, Ore., Seattle, New York and Amsterdam.

“It’s clear they like to have a lot of fun,” says architect David Koel, a design principal at Cushing Terrell.

The couple branded their home KnightHawk Lodge—a combination of their high school mascots (the Knights of Hellgate High School in Missoula for him and the Hawks of Mountlake Terrace High School in Mountlake Terrace, Wash., for her). They had a graphic designer friend from Nike design a logo that’s half hawk, half knight, which they put on T-shirts and cups.

Mr. Sprunk, who is currently on the boards of General Mills and Bombardier, graduated from the University of Montana with a degree in accounting in 1986, already married and a father. Ms. Sprunk, who is a community volunteer and consultant, graduated from Washington State University in 1988 with a degree in business administration and married a commercial real-estate broker in Seattle.

The Sprunks first met each other in 1989 when they were both working at PricewaterhouseCoopers, where one of Mr. Sprunk’s clients was Nike. In March 1993, he went to work for Nike and moved to Amsterdam in 1995, becoming the CFO of Nike Europe and then the general manager of European footwear. In 2000, he moved to the company’s headquarters in Portland, Ore., and was made COO in 2012. The couple got together after they were both divorced and got married in 2013.

They chose Flathead Lake as their second home location because Mr. Sprunk grew up going there every summer and still has friends from third grade to college who live in the area. His father lives in the house across the lake. Ms. Sprunk, who grew up near Seattle, used to vacation at a ranch called Flathead Lake Lodge every summer.

The couple now splits their time between the lake house and their primary home in Seattle, a historic mansion they bought in 2020 for $8 million and just remodelled for $3 million in the Queen Anne neighbourhood.

“It’s a his and hers hometowns situation. We both love both places,” says Ms. Sprunk.