Because its majestic view of the Rockies and expansive Flat Head Lake gives soakers the sensation of sitting on a throne more than in a spa. Because the symmetrical, 14-foot-high columns and oversized wooden trusses make the room feel protected, but not closed in. Because the raised gable framing Montana’s renowned Big Sky mimics the snow-capped peaks beyond. Because the floor is made from the reclaimed wood of wine oak barrels. Because with its nearby changing rooms, bathroom and benches, the room is perfect for a party of two — or dozens. Because the whole structure grows out from a rocky cliff 60 feet above the ground. Because it took almost a dozen workers two years to complete this multifaceted installation.

In Bozeman, Mont., where the city is located 4,800 feet above sea level, each man’s home is his castle.

So the homeowners at this spa installation site wanted a majestic view of the nearby Rocky Mountains and Flathead Lake, the largest natural freshwater lake in the western United States. In addition, they felt the spa’s enclosure deserved no less than the rest of the house’s 5,000 square feet of high ceilings and great, wide-open rooms.

Thus, the spa space literally became an extension of the house.

“There’s a walkway out to the hot tub off the informal living area, which connects the enclosure to the house over a cliff,” says Jerry Locati, co-owner of Locati Architects in Bozeman. “Halfway to the hot tub, there is a covered deck with an outdoor fireplace and a barbecue, and then you keep walking a little bit further — the hot tub is about 50 feet away from the house — and you come to this really cool structure.

“The hot tub is the main reason for the structure, but it’s also a gathering area where you can sit and have a glass of wine,” Locati notes.

Within the 24-by-30-foot enclosure are a dressing room, bathroom and benches around the walls. The spa itself is nestled between two 14-foot-high, classical white columns and cantilevers over the edge of a 60-foot-high cliff. Glass panels on the left side of the enclosure block any winds.

“The columns and the gable were built high to incorporate as much of the view as we could,” Locati says. “The mountains are also where we picked up the very natural color for the siding.”

The floor of the structure is composed of reclaimed oak wine barrels — the same material the first hot tubs were made from.

Woods in the rest of the Montana structure are mostly redwood.

Because the entire enclosure was built on a rocky cliff near the home, the construction crew had a number of obstacles to overcome. “The challenging part about this whole project was coming out of the ground — we didn’t want to make it look like it was just stuck there,” Locati says. “We wanted to tie it into the rockwork [so it would look] like it was meant to be there.”