Roland Welker has been a woodsman nearly all his life. Before heading into the wilderness to compete in Season 7 of the History Channel’s survival series Alone, he, like most participants, had a rough plan. He’s burly and knows how to chop wood—of course, he would build a log cabin. But Welker had no idea where he was going nor what materials would be available on the land. He knew he’d have to get creative quickly.

Each season of Alone takes place in a remote location and features a group of 10 survival experts—typically hunters, architects, carpenters, archers, engineers, and artisans with various outdoor skills and a shared desire to push their primal instincts to the limits for a prize pot that’s increased from $500,000 to as much as $1 million in recent seasons. Dropped off in a desolate landscape with little but their wits, ingenuity, and camera equipment with which to film themselves, their first instinct should be to scream and panic. But their most important tasks for the next possibly 100 days will be to find food and build a long-term shelter tough enough to sustain extreme cold, predators, hunger, and, as the title implies, loneliness.

Once a helicopter deposits each of them in the wilderness and flies off, contestants are on their own. They know they’ll need to start a fire. Maybe they’ll stitch together a gillnet to catch fish (or, in one competitor’s case, assemble a boat). The endgame is longevity. (Players are given GPS trackers and a satellite phone, which they can use to call to “tap out” at any point in the challenge. The last person standing wins.) And as such, their homes, like ours, are important. They need to be sturdy, wind-resistant, waterproof, snow-repelling, airtight, and crafted from materials in their surrounding environment, so when the result is a nice, livable domain, it’s rewarding for all parties, including the unskilled viewer amazed from afar.

Admittedly, it’s sadistic voyeurism, watching desperate people problem-solve on the same grounds as grizzly bears and wolverines as they spend weeks constructing shelters they might sooner desert for the comfort of home. When Alone premiered in 2015, the shelters were mainly lean-tos (open-faced shanties set against an existing foundation like a tree) and simple facades. In Season 3’s Magellanic Forest in Argentina, Callie North built an A-frame cabin with a separate outdoor sauna for both practical (hygiene) and ceremonial purposes. Over the next few seasons, the homes evolved into clever debris shelters and elaborate log cabins with stairs, doors, knobs, and decorative features; the History Channel has even released a digital series devoted to them.

“I could stand straight up and down and put my pants on like a human being. I wasn’t crawling around like a bear or something all winter.”

Welker’s roughly 12-by-6-foot Rock House was essentially a megamansion in the middle of the Canadian arctic. After spending three days exploring, he found a large rock formation and chose it as a protective home base. Moving around mammoth stones, he excavated to set a foundation in the dirt and forged his log cabin around it, using the giant ax and saw he brought with him. (Contestants can bring 10 pre-approved items like fishing lines and sleeping bags, though obvious advantages like guns are forbidden.) As one of the show’s helpful pop-up facts notes in an episode: “Rock walls, used as thermal mass, can absorb and retain heat for days.” The tradeoff is that a bigger shelter could at the same time leak heat, so Welker had to keep his fireplace burning nonstop.

“It was a ballsy move. You’re spending a lot of calories, but a hundred days is three weeks shy of a third of a year. That’s a long time to squat around in a half-assed shelter. I wanted to be comfortable,” he says. “You got no measuring tools, no levels. So you gotta have a good eyeball. You gotta be naturally engineer-minded.” It took him 19 days to move into his self-named Rock House, and he spent three more weeks completing it. By the end, he says, “I could stand straight up and down and put my pants on like a human being. I wasn’t crawling around like a bear or something all winter.”

The most successful shelters carry players beyond the initial month into the harshest part of winter. Season 8’s Jordon Bell spent his first week crafting a beautiful log cabin with a single-slope roof, etching saddle notches to secure the logs in place. After a hard day’s work, he was visited by a bear that night. “I guess I need to get that cabin built,” he says with a hearty laugh into an infrared camera. Over the next few days, he added a door with a hatch and carved his family’s initials on a ridge beam atop the cabin.

Most participants start by making a temporary pad under a tarp. North worked quickly to find a site, using bamboo as insulation for the sides. Instead of the darker tarp supplied by the show as part of basic survival kits, she brought a white tarp to reflect light into the space. She also laid out rock flooring and made a broom for cleaning. “Then I could have my shoes off when I came in and have an area separate from the outside that made it feel very comfortable and homey,” she says.

Her partner outside the show (they connected after both being on it), Randy Champagne, crafted a simple, three-sided structure during Season 2 on Vancouver Island. When he returned for Season 5 in Mongolia, where it was colder, he learned from the past and opted for an enclosed log cabin. “I wanted something simple, efficient, and small because a smaller space is easier to warm up,” he says. “But also something I could come home to and feel like when I got back to my shelter, there was relief.”

It’s all about stamina (the show frequently references “caloric expenditure”). So a common strategy is to use energy early on when it’s more expendable. U.K.-based archeologist Theresa Emmerich Kamper had a few shelter ideas heading into Season 8. After arriving at the edge of British Columbia’s Chilko Lake, she decided on a pithouse, a partially underground dwelling commonly used by Native Americans for thousands of years. (Notably, the Alone casts are predominantly white survivalists using timeworn, nomadic methods.) Kamper had made pithouses as a child but never an adult-sized structure, which she knew would be efficient at containing heat, with the ground acting as insulation. She didn’t bring a shovel because she knew she could craft one out of stones if needed.

Before being taken to their locations, Kamper says the show’s safety crew told competitors there was a size limit on their shelters, which forced her to think smaller. On Day 1, she found a spot and dug a waist-deep hole using a stick, a rock, and an elk jawbone she discovered near her camp. For her framework, she fashioned bark into shingles and dug a hole inside her shelter for food storage, covering it with rocks to safeguard it from bears. Once the weather hit below zero, the pithouse was cozy enough for Kamper to stretch out and walk around comfortably in a t-shirt.

The process burned up calories but also saved her in the long run. A body in survival mode is never in homeostasis, either shivering or sweating to stay warm and burning crucial calories. “When I didn’t have a lot of energy and was hanging on to my calories, giving my body some place to be very comfortable and not burning excess calories would be really important,” she says. “Also, it’s just nice. It’s nice to come home, take off your outdoor clothing, have it all dry out, and have a place to sit around in your one layer of long johns.”

Part of the fun in living vicariously through obsessive adventurists is debating how inventive you might be under the circumstances. The show has a dedicated fanbase devoted to pointing out wins and fails. Going structurally small saves energy and warmth—as one Reddit user wrote about Kamper’s pithouse, “I thought the tide would be a factor, or the wind coming off the lake. Apparently, she had built one of the most efficient shelters ever on the show.”

During Season 9 out in Labrador, Canada, Teimojin Tan, a military vet and doctor from Montreal, noticed a plateau near a creek. Going into filming, he planned to integrate the land’s natural features into his shelter, which he affixed to the trunk of an old spruce tree. (This meant less wood chopping and potential injury). Below his temporary tarp, he constructed a debris shelter, using rolled-up moss as brick for insulation. Beneath that was a bunk bed covered by a smaller tarp. He wanted thick walls like a fortress—basically a multi-layered home.

Inside, he dug a roughly two-foot fire pit. Like Kamper’s pithouse, the ground served as a firewall to reflect heat into the shelter, eliminating cold gaps and allowing Tan to walk barefoot. “I was really sleeping under three different shelters,” he says. “There were times when moisture dripped on the inside of my shelter, but my sleeping bag and I never got wet because of that extra tarp layer.”

It’s unusual for reality TV contestants to also have to double as videographers. Moving cameras around and sometimes reshooting to capture moments while also narrating your every move prolongs the process in unpredictable ways. “It slows everything down exponentially,” says Kamper.

“If it don’t happen on camera, it didn’t happen,” adds Welker. “No matter how great it was.” There’s also no feedback or sounding board for design ideas and inevitable mistakes. Competitors have built fireplaces and chimneys to avoid smoke inhalation, but many of those shelters caught on fire due to the wood.

Viewers also don’t get to see all the finished shelters, which producers disassemble after each contestant leaves. Tan says he wove spruce roots into large baskets you might find in Crate & Barrel. Both North and Kamper added organizational features like hangers and shelves. While the exterior is all but premeditated for most, those interior details tend to happen more organically. “I’m not somebody who puts up pretties, but I like my things to have a place. It’s nice when that place isn’t on the floor,” says Kamper. “You weren’t tripping over stuff if you needed to get out in the middle of the night and it’s absolutely pitch black. You’re not going to faceplant into the stairs.”

That a place like that would even have stairs is a feat. But comfort and home mean something different to everyone. “If you can give it a touch of home, then yeah, that might increase your chances to stay longer,” says Welker. “But I don’t need all that. When you put me in that arena, I turn into the old mountain man that doesn’t need shit except meat and branch water.” Not making it to the end doesn’t mean their shelter was a complete fail—after all, there can only be one winner. “People watch it and they’re like, ‘Oh my god, he or she tapped out on Day 10.’ They just don’t understand,” says Welker, whose Rock House fared extremely well. “It’s very, very, very difficult.”

In the same way that modern homes have evolved to fit people’s changing needs, so have the homes on Alone. Many of the participants’ knowledge comes from years of research and experience building shelters on their own. Now with nine seasons of trial and error to pull from, incoming contestants have examples of successes and failures, opening the doors for more innovative structures in the future. “They’re getting a little nicer. People have put more time into their shelters because they don’t want to be miserable for however many days they’re out there,” says Champagne. “They realize the importance of moving from quote-unquote survival to a point where you’re sort of thriving. You’re living as opposed to just making it.”

Top photo of Theresa Kamper, the first contestant in the show’s history to build a pithouse, mid-build. Image courtesy of The History Channel.

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