The wealthy are paying big money to pump oxygen into their mountain homes

For those guests, Rost installed a home oxygenation system in every bedroom of the 12,000-square-foot house. Now, 10 oxygen enrichment machines, located in a storage area inside the house, pull oxygen from the air outside and pump it to four bedrooms and a bunkroom through blue tubing built into the walls during construction.

The extra oxygen can make the rooms feel like they are between 3,000 and 5,000 feet above sea level, not 2 miles. Built into the mountainside at The Ridge, a development of 25 home sites in Telluride’s ski area, the modern rustic house has a mining theme echoing the town’s past, complete with a rail track in the floor for ore carts delivering candy to a home theater.

It cost $18 million and took two years of planning, followed by six years of construction. Rost, 59, who retired as the owner of a pipe-fitting company, has never had symptoms of altitude sickness. But since he and his wife, Monica Rost, 58, moved in last December, his brother from Tennessee and his nephew from Atlanta have slept with extra oxygen, which helped them adjust to the thin air.

“You don’t have to sit around for two or three days waiting for the natural acclimatization to occur—we’re fast-tracking that process," says Adam Roberts, chief operating officer of Altitude Solutions, an oxygen-enrichment company in Glenwood Springs, Colo., that installed Rost’s system. “People spend a lot of money on their homes in the mountains. But what’s the point if you can’t enjoy it, if you can’t even go skiing?"

The next three houses being built at The Ridge will also have oxygenation systems. Similarly, RA Nelson, an Avon, Colo.-based custom home builder with projects in Vail, Aspen, Beaver Creek and other ski towns, now includes the necessary tubing in every new construction. BJ Lindsey, a custom builder in Angel Fire, N.M., a Rocky Mountain town with a base elevation of 8,600 feet, puts it into both high-end custom homes and speculative houses. Energy1, a Bozeman, Mont.-based company, has installed over 140 systems over the last seven years in Big Sky alone. The firm now equips all new homes at the Yellowstone Club for future oxygenation, along with more houses in the nearby communities of Beehive, Moonlight and Spanish Peaks.

Luxury resorts are taking note. Four Seasons Private Residences in Telluride, set to open in 2028, will have oxygenation in all hotel and condominium bedrooms.

“Home oxygenation is where motorized shades and lighting control were 15 years ago," says David E. Luckan, president of Invigor8 Air Design, an oxygen-enrichment company in Park City, Utah. Once rare and considered high tech, he explains, those features are now standard in luxury homes.

At 8,000 feet, most lowlanders are affected by the reduced oxygen at high elevations, says Dr. Peter Hackett, a professor at the Altitude Research Center at the University of Colorado Anschutz Medical Campus. At 9,000 feet, they are getting 30% less oxygen than at sea level—enough to cause shortness of breath, headaches, nausea and, most commonly, poor sleep. More oxygen in the bedroom means more sleep and, as a result, more strength to acclimate, says Hackett, who has climbed Mount Everest using supplemental oxygen.

“The problem is no oxygen. If you give oxygen, you’re going to be fine," he says. “It’s a very expensive proposition, so something generally only the wealthy can afford. But it works."

When Rost began to build in 2017, his oxygenation system cost $75,000. At today’s prices, it would cost $150,000, according to Altitude Solutions. Each enrichment machine costs $15,000, and Rost’s spacious primary bedroom required four of them. The smaller bedrooms needed one or two. A single unit can enrich around 2,000 cubic feet of air volume, so the larger the volume in the room, the more units it needs to increase the concentration of oxygen in the air. The equipment must be in a temperature-controlled space to protect it from winter cold, plus fans to prevent overheating. At Mile High Training, a New York City-based company, treating a small bedroom starts at around $30,000 but can cost as much as $250,000, depending on the volume.

Altitude Control Technology, a home-oxygenation company in Edwards, Colo., has oxygenated primary bedrooms that cost $150,000 and $200,000, according to Bill Sinclair, president and chief executive. Most cost between $35,000 and $45,000 and get installed in the primary bedroom and one or two guest rooms. He recommends adding the pipes to deliver oxygen during construction, so new homeowners don’t have to reopen walls when altitude sickness strikes. Laying those pipes cost between $1,500 and $3,500 per room. “It’s so inexpensive to do it during that stage," says Sinclair. “Compared to the cost of the house, it’s nothing."

For years, Bob Fraser struggled with the altitude in Breckenridge, Colo., one of the highest resorts in the country, every time he arrived from his home in Kansas City, Mo. For the first two days of his stay, he had headaches, nausea and trouble sleeping.

Shortly after buying a lot to build his own Breckenridge home in 2021, Fraser, a 64-year-old partner in Aspen Funds, a private-equity firm in Overland Park, Kan., and his wife Lauren Fraser, 63, toured a local show house with a home-oxygenation system.

“What? Is that a thing? I didn’t know that’s a thing!" he recalls thinking. “I thought, ‘This is great.’ "

The main floor of the six-bedroom, 6,500-square-foot house the Frasers were planning to build was at 9,800 feet. Fraser also worried that the altitude would deter his 87-year-old mother from visiting. So when building the $6.5 million Mountain Modern home overlooking Lake Dillon, he called on Mile High Training to install an industrial-grade, high-flow system that pumps oxygen into each of the home’s six bedrooms, a bar area and a sitting room. Weary, lightheaded skiers and hikers can connect nasal cannulas to copper outlet ports on the backsplash of the bar to inhale more concentrated oxygen.

“Our guests love the oxygen bar," says Fraser. “It’s kind of fun. You sit around with these cannulas in. You have essential oils in there. It’s super popular."

From a central control panel, the Frasers select which bedroom needs oxygen. To ensure the precious gas can’t escape, the rooms are highly insulated, with mechanical drop sweeps that come down from a hollow space in the door when it shuts, to close any gap between door and floor. Oxygen flows in from an outlet high above the bed. A sensor measuring the oxygen content in the air is mounted to the wall near the bedside tables.

Mile High founder Matt Formato says the system aims to get the room to feel like it is at 2,500 feet in two hours. The more rooms that receive oxygen, the longer it takes. At Fraser’s house, completed in 2022, the system cost $135,000, not including the power supply and custom ventilation system in the mechanical room near the garage, where the machinery is located. But it has lessened altitude problems for both Fraser and house guests. On a visit in September, his son’s parents-in-law initially struggled to sleep. Once the principal bedroom, where they stayed, came down to a simulated elevation of 2,000 feet, they slept like babies, according to Fraser. His own mother has yet to visit.

“We put in the system for my mom, to entice her to come up," he says. “But so far it hasn’t worked."

Some homeowners say it takes time to figure out the system, especially how long it needs to reach the desired oxygen level in each room. For ease of use, many are now controlled on a phone app and programmed for a set schedule. In Park City, homeowner Brent Andrus, recently asked Altitude Control Technology to install a $50,000 oxygenation system in the primary bedroom of his, 9,000-square-foot, five-bedroom house. The system switches on around 6:30 p.m. to fill up the room before Andrus and his wife, Cheri Andrus, go to sleep between 10:30 p.m. and 11 p.m. Andrus, 78, co-owner of Huntington Hotel Group, a hotel-development company in Irving, Texas, says the oxygen-rich air is “miraculous" because it ensures that he takes in enough oxygen during sleep. But it takes between four and five hours to bring up the room’s oxygen level.

“It’s not instant," he says.

Before Eric Garrett from Nashville, Tenn., bought a seven-bedroom, 11,000-square-foot log home in Telluride’s Mountain Village for $9.5 million in 2021, he had been coming to Telluride for some 20 years. For all those years, including on his company’s annual ski retreat, he initially felt groggy, tired from poor sleep and often unable to ski a full day.

“People here have a hard time sleeping," says Garrett, 47, chief executive of a real estate, construction and asset-management company that bears his name, based in Greenwood, Ind. “I’m one of those people."

So when he and his wife, Rhonda Garrett, 47, bought the rustic log house with a view of the Wilson Massif, located at 10,000 feet at the intersection of the Galloping Goose and Double Cabin ski runs, he says extra oxygen “was a must." Mile High Training installed a $125,000 system in the primary bedroom and two other bedrooms. Connecting the pipes in the house, built in 2010, was painless: The attic, where the compressors would be stored, was right above the primary bedroom, so the oxygen wouldn’t have to travel far.

But the system also required a thick power cable to connect the attic with the power supply on the far side of the house, near the garage. This meant opening walls and ceilings, creating a pathway for the cord through the full length of the house and patching it all up again.

To make the bedrooms airtight, Mile High painstakingly checked the log walls to ensure that the sealant between the massive logs hadn’t cracked and closed any gaps to prevent oxygen from leaking out. Two fireplaces are gas-burning, covered by glass and have a direct-vent technology that draws fresh air from outside in one pipe and expels air through another, without drawing air from inside the bedroom. The primary bedroom’s size and 20-foot ceiling required an extra compressor. And the bedroom had two doors that open to the bathroom and two closets. Oxygenation companies generally include adjacent or connected bathrooms in the calculation for the oxygen needed to fill a room: even if there is a door, sleepy occupants too easily forget to close it during the night.

Garrett calls oxygenation a “game-changer" for sleeping at his high-altitude home. But doors are a challenge. “I’m always running around telling everyone to keep the door closed," says Garrett who has three children, 19, 11 and 10. “The system turns on at 5 p.m. By 8 p.m., I’m pretty serious about keeping that door closed."

Write to Cecilie Rohwedder at cecilie.rohwedder@wsj.com