This is part of our Road Trip 2018 summer series "Taking It to Extremes," which looks at what happens when people mix everyday tech with insane situations.

I am trying really hard to make this nuclear bomb shelter feel like a home.

The room is small, just enough to fit a bunk bed, a padded bench, a ladder in the middle and an air filtration system, but not much else, not even a toilet. I'm looking for where I could put books, or at the very least, a stash of canned beans and bottled water to stay alive.

I'm a little uneasy. Maybe it's how cramped it feels in here. Maybe it's the metal ladder interrupting the feng shui of the room. Or maybe it's the fact I'd have to live in this nuclear bomb shelter for the rest of my life if the apocalypse ever struck.

I'm inside a showroom version of the BombNado Disaster Shelter in Montebello, California, to see what it's like living in a nuclear bunker. If it were real, I'd be deep underground. But instead, I'm out in a metal box next to Interstate 5 during a heat wave.

Bomb shelters are no longer a relic of the Cold War. Back then, schools and cities around the country conducted air raid drills as fears of a nuclear war between the US and the Soviet Union reached a fever pitch. In 1962, the Department of Defense even printed a handbook for building fallout shelters in your backyard or your basement.

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Now there's second boom (no pun intended) in demand, fueled by rising political tensions; worsening wildfire, tornado and hurricane seasons; and fears of terror attacks. Atlas Survival Shelters told Germany's Die Welt newspaper that it sold 1,000 shelters in 2017. Real-estate paper The Real Deal reports that Rising S Company, in Texas, saw 700 percent growth in international sales last year, mainly in Japan.

Bomb shelter makers tell me customers range from Silicon Valley's tech billionaires to working-class homeowners who want a safe place to hide in case of disaster.

"They don't just have to be for an apocalyptic situation," says Ron Hubbard, founder and CEO of Atlas Survival Shelters, which offers about a dozen types of shelters. "Here in California, with all the wildfires we have, that's actually our No. 1 concern right now."

You can still build your own shelter, or now you can just can buy one. Prices start at $19,000 (the cost of the BombNado), but they can go as high as $8.3 million. For $19,000, you get the basic bunker, about 8-by-8 feet, with a bed, toilet and an air filter -- essentially a dorm room. Higher-end models can be more luxurious than most homes and include pools, hot tubs and shooting ranges. You can add surveillance systems, too, if you're willing to pay the price.

The BombNado is one of Atlas' more popular models, with 40 sold in the last two years. But it left me wishing for better postapocalyptic real estate.

The basics

The padded bench in the BombNado shelter is about as comfortable as a minivan seat. It's a sweltering day in early August and the ladder is too hot to touch. I also realize the book I brought to fight off ennui isn't going to last long, so I step out to see the rest of the factory.

If you've got the money to pay for it, it doesn't matter if it's bizarre or not. You've earned it." Gary Lynch

The California facility supplements Atlas Survival Shelters' main factory in Sulphur Springs, Texas. Hubbard, 56, tells me he wants to be the "Henry Ford of bomb shelters," with the goal of making bomb shelters something everyone can afford, not just the rich.

The factories always have 15 to 20 bunkers ready to ship out to eager customers. Demand comes in waves. He says the rush for shelters was at its peak last August, with up to 200 calls a day, when President Donald Trump threatened North Korea with "fire and fury."

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Hubbard has the energy of a teen when it comes to talking about his bunkers. When he greets me from his office, he's wearing a blue tank top -- appropriate considering the temperatures are inching up toward 100 degrees Fahrenheit. But then he heads to his car, where he pulls out five different colored shirts, asking me which one would work best on camera.

If anything, Hubbard is prepared, whether it's for a nuclear blast or a camera crew arriving.

He shows me the shell of a $25,000 bunker that's headed to a family in Calabasas, California. It's unfinished: Cardboard is laid out on the floor, and the black walls still need to be reinforced with steel. It's also pretty small. I walk from the door to the back in just seven paces.

The customer intends to use it as a wine cellar as well as a fallout shelter, he says. These multipurpose shelters are Hubbard's way of pushing bunkers into the mainstream, promoting them as a luxury and vanity purchase and not just a means of survival.

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The marketing pamphlet for the wine cellar bunker, named the WineNado, barely mentions how exactly the shelter would protect you if missiles obliterated your home. But there is this line: "The fact that the shelter is hidden underneath the kitchen counter will bring jaw-dropping wows from your friends when you show them the hidden entrance to your new favorite room."

While Hubbard maintains that safety is paramount, it's the luxury that gets people excited.

Safety first

Shelters can be relatively low-tech affairs.

Though they're often constructed with reinforced steel or built in galvanized corrugated pipes, it's not the building materials that protect you from bombs, tornadoes and wildfires. Being at least four feet below ground does that.

"The earth is really what provides that level of protection," says Gary Lynch, the general manager of Rising S Shelters, based in Murchison, Texas. "That's the reason they bury them."

But a shelter needs to do more than withstand a blast. Most shelters also come with an NBC (nuclear, biological, chemical) filtration system that makes sure the air is safe to breath. It comes in handy for chemical or nuclear attacks, or when the air is polluted with dangerous chemicals from wildfires.

Besides breathable air and protective barriers, everything else is a plus.

Lynch says shelters can include fingerprint-protected entries as well as surveillance systems that show what's happening outside the underground bunker -- something he calls "virtual windows." He thinks it might be possible to have a kind of smart nuclear bunker, with the ability to control lights and appliances from a smartphone and voice assistants like Amazon Alexa and Google Assistant.

"If you can do it in a regular home, we can do it in a shelter," he says. Even so, it's difficult to say how functional any kind of internet services would be after a nuclear holocaust.

Hubbard is also exploring other technologies to keep you alive. The walls in his office are plastered with posters, blueprints and ads for accessories you can add to your underground bunker, as if it were pulled out of some Doomsday Ikea catalog.

If you don't have the land to put your shelter in, it's like buying a boat without an ocean to sail it on." Ron Hubbard

One of those posters shows the Power Station 3000, a stationary bicycle that connects to a battery bank. Ride for 15 minutes, and it's charged, according to the poster.

"Anyone can ride -- kids, teenagers, adults, athletes and senior citizens. Very smooth and very easy to ride," it reads.

It's nice knowing that if we're on the precipice of the end, I can still tone my thighs while charging my phone.

Fallout in style

Hubbard wants you to think about bomb shelters the same way you'd consider getting a swimming pool. They cost about the same, but only one will keep you safe if disaster strikes. Spoiler: It's not the pool.

"Most people, when they think of a bomb shelter, think of something cold and wet and downtrodden," he says. "I am changing that persona of a bomb shelter."

Some shelters push that luxury to extremes. Take the Underground House, a 16,000-square-foot shelter built in Las Vegas in 1978 that comes with a dance floor, putting green, fireplace, wet bar, laundry room, guest house -- and yes, a pool -- all beneath the earth.

The Society for the Preservation of Near Extinct Species bought the house in March 2014 and has pushed to keep the home's details private since. The group is extremely secretive, without so much as a website to describe what it does or how many members there are. It's been listed as a nonprofit educational organization since September 2014, and the group's leader, Mark Voelker, is a doctor with decades of experience in cryogenics.

It had zero income in 2012, according to public records.

He couldn't be reached for an interview.

Tee Thompson, a member of the society, says it often receives letters and calls from people threatening to break in and use the shelter in case of the apocalypse. One woman, she recalls, offered to help repopulate the planet if she were given shelter there. Thompson said they declined the offer.

The organization also declined to give me a tour of the Underground House.

Rising S

The Underground House may be one of the more extreme examples of ridiculously lavish shelters, but other bunkers can give it a run for the money. Lynch says he's built two with horse stables, both for customers in Napa Valley, California.

About half of Lynch's customers, many of whom prefer to stay anonymous, are Silicon Valley billionaires. And most, he says, opt for some luxury elements, like smart home perks. "If you've got the money to pay for it, it doesn't matter if it's bizarre or not. You've earned it."

Rising S offers three luxury models. The Venetian ($3.3 million) includes "enough beds for 22 people" and three master bedrooms. Looking for something a little more civilized? The Aristocrat ($8.35 million) includes a gym/health center, sauna, swimming pool, game room, bowling alley and media room with theater seats.

It can take up to a year for Lynch to make these luxury bunkers.

Hubbard tends to stay on the humbler side with his shelters. He's concerned that lavish shelters, while decked out, might not actually be optimized for disasters.

The majority of bomb shelter makers -- a small crowd of about seven or eight businesses -- rely on "Principles of Protection," written in 1991 by Walton McCarthy, a mechanical engineer with nearly 40 years' experience designing and installing bunkers. It covers protection from nuclear, biological and chemical weapons and, of course, natural disasters like tornadoes and earthquakes.

But there aren't any mandated safety requirements for shelters like there are for homes or cars.

"There's no agency to regulate this industry," says Hubbard. "There's no regulations or codes."

The simple BombNado shelter I stayed in didn't have any bells or whistles, but Hubbard insists I'd be able to survive in it.

A pool would've been nice, though.

Land grab

Though there are plenty of customers with deep pockets in Silicon Valley, there aren't many shelters in nearby San Francisco, where open, seismically stable real estate is at a premium. It's why Silicon Valley types install their shelters elsewhere, says Hubbard.

"You can have all the money in the world, but if you don't have the land to put your shelter in, it's like buying a boat without an ocean to sail it on," Hubbard said. "The problem up there in Silicon Valley is that the guys in San Francisco, they have to find land."

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But just because the land isn't there doesn't mean there's no demand. If you can't dig a large enough hole on the property, you can't have a shelter, Hubbard often has to tell potential customers.

Hubbard thinks he has the solution, though. In July, he launched a "bugout community" about 170 miles north of downtown Los Angeles. It's 300 acres of open land that people can buy and use to build underground bunkers.

Think Coachella, but for doomsday preppers. For now, he's watching to see how it works out. If it's a success, Hubbard wants to provide something similar for the many potential customers in the San Francisco Bay area.

"It's really sad. Where would anybody in San Francisco go?"

San Franciscans might have to make do with something as cramped as the BombNado. But after spending just 30 minutes in it, I find myself yearning for wide open spaces. Too bad I don't have a spare $8 million for The Aristocrat. I need to work on my backstroke.

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