Kathryn Bigelow’s ‘House of Dynamite’ Brings Nuclear Danger but Homeowners Have Already Been Digging In. What’s the ROI on Backyard Bunkers?

Kathryn Bigelow’s new movie, "A House of Dynamite," lands on Netflix this weekend with a bang. In her latest, the Oscar-winning director behind "The Hurt Locker" and "Zero Dark Thirty" takes on the unthinkable: a nuclear strike on American soil. 

But for many, that premise no longer feels like fiction, and fears of potential nuclear conflict are pushing investments in backyard bunkers through the roof. 

The U.S. market for fallout and bomb shelters is now valued at roughly $137 million and is projected to hit $175 million by 2030, according to BlueWeave Consulting. Globally, the market is as large as $23 billion today and is anticipated to hit $37 billion by 2030.

But as the shockwaves from the bunker boom spread, a question lingers above ground: Do backyard bomb shelters actually offer a return on investment—or are they a panic purchase that could hurt your home’s resale value?

To find out, we spoke with builders, real estate professionals, home-improvement experts, and one guest of a luxury bunker about what it really takes to go nuclear-proof—and whether the payoff is worth digging for.

What it takes to build a real bunker

“A real bunker is like a small submarine buried in the ground,” says Orlando Penner, a builder with South Country Sheds in Florida. “It has to hold pressure like a tank, move air, and it has to stay solid while surrounded by soil that’s constantly shifting and pulling at it.”

That’s no easy task. The Federal Emergency Management Agency's 230 page Design Guidance for Shelters and Safe Rooms notes that effective protection against man-made threats requires independent structural systems, reinforced walls, and specialized ventilation to mitigate chemical, biological, radiological, and explosive risks.

It’s a level of nuance in design and construction that’s hard to come by.

“The biggest misconception is that a few feet of concrete makes something ‘nuclear-proof.’ They don’t,” Penner says. “Just concrete alone will crack under vibration and soil pressure. … A real shockwave would crack it as a nutshell under a boot.”

FEMA guidance similarly stresses hardened construction—reinforced concrete, shear walls, and blast-resistant joints—as a core feature of any shelter designed to withstand pressure waves and debris impact, while also emphasizing that such shelters aren’t a realistic response to nuclear war.

The agency’s 105 page Nuclear Detonation Response Guidance recommends the public simply get inside and stay there, ideally in a basement and away from exterior walls. While it may not be enough to withstand a blast, that protection alone may be enough to mitigate exposure to nuclear fallout.

FEMA's guidance falls within a long-held survival maxim: KISS, or “keep it simple stupid.” And there’s nothing simple about building a nuclear bomb shelter.

Douglas Conner, a home-improvement professional, agrees that many homeowners underestimate the complexity.

“Some homeowners think that just digging a deep hole and putting in reinforced walls makes a bunker ‘nuclear-proof’. In truth, real nuclear resilience requires unique shielding, blast resistance, and ventilation that can deal with extreme radiation, shockwaves, and fallout from a nuclear blast.”

That ventilation is key. FEMA specifies pressurized air filtration systems for shelters seeking high-level protection, and minimum space and airflow standards: 10 square feet per occupant and 6.5 feet of headroom.

In practice, that means balancing depth, soil stability, drainage, waterproof membranes, and rebar reinforcement—all while keeping the structure breathable and dry. And that can get expensive. 

As Penner puts it, “The deeper underground you go, the stronger and pricier it gets.”

How much does a backyard bunker cost?

Given all the requirements of making a bunker truly nuclear-proof, building one isn’t cheap—and rising demand is pushing prices higher. Affordable entry-level options, like Atlas Survival Shelters’ BombNado, start around $19,000, but that’s just for the most basic, prefabricated models.

“On average, it may cost between $40,000 and $150,000,” says Thomas O’Shaughnessy, vice president at Clever Offers. “Added features such as depth, materials, ventilation, and the user's need for blast resistance can significantly increase costs.”

Penner puts the range even higher for custom, underground designs.

“A functional underground bunker that won’t flood or collapse runs from $300 to $600 a square foot," which can get you into six figures pretty quickly.

And for larger, reinforced models with full systems, Conner clocks them at $250,000 or more.

Beyond size and materials, the biggest cost drivers include soil composition, excavation depth, waterproofing, drainage systems, blast-valve ventilation, power generation, and ongoing maintenance.

The ROI bomb: Do bunkers add or undermine property value?

Even for homeowners who can navigate the engineering and permitting maze, one question looms largest: Will a bunker actually make your property worth more—or less?

“A bunker rarely boosts resale value. They’re more of a curiosity,” says Penner. “If it’s properly built and dry, it might appeal to a niche crowd. If not, the word ‘bunker’ raises questions about drainage, safety, or past flooding, which can be considered as extra liability down the road.”

O’Shaughnessy agrees that most buyers don’t see bunkers as a selling point.

“Bunkers are not usually added value to a property. Rather, they might represent a negative to other would-be buyers.”

Part of that negative perception may come from the psychological gray zone bunkers inhabit. Their mere presence raises questions about what inspired it—or what it’s hiding.

One guest of a luxury bunker we spoke to who asked that we not use his name, says, “The air feels completely sealed off from the outside world, and it’s completely, eerily silent. … It definitely felt safe in that it’s so removed from reality. But by the end of our few hours down there, everyone was relieved to escape outside.”

That tension—between physical safety and psychological strain—captures a central paradox of bunker living: They’re underground, cut off from sunlight, fresh air, and any sense of connection to the world above, the very features that most homebuyers instinctively value.

“[I’m] not sure how long mentally you would be able to feel comfortable,” he adds.

But there are bunkers and then there are underground mansions, like this luxury underground property in Las Vegas that features five bedrooms, six bathrooms, and a total of 14,620 square feet found 26 feet underground.

Built in the 1970s by Jerry Henderson and architect Jay Swayze as the “world’s largest Atomitat Cold War Era luxury bunker,” it's currently on the market for $8.5 million, highlighting the costs of constructing underground nuclear-proofed spaces. But this property comes with a historical designation and special permits that offer an upside to any buyer: potential income.

“I think the incoming buyer would most benefit from utilizing that as a revenue stream at the property and providing the historical status on to it,” the property’s listing agent, Holly Erker of Is Luxury, says.

“I know I get several calls a week for people that just want a tour, and if the incoming buyer were to exercise or take advantage of that it could be a huge revenue stream just for ticketed tours," she adds.

That passive income can make a meaningful difference in the return on investment.

Fail to prepare, prepare to fail

Owning a bunker isn’t a one-and-done project—it’s an ongoing commitment. And like another popular survival maxim suggests, if you fail to prepare for the costs of maintaining a bunker, you prepare to fail. Because unlike a basement or storage shed, a shelter’s systems must perform perfectly when everything else fails.

"You don’t just pour a bunker and walk away,” says Penner. “You need to test air systems, run the sump pump, inspect for rust, and reseal joints every year. It's a constant maintenance cycle.”

Those tasks aren’t optional. FEMA guidelines call for routine inspection and testing of ventilation, power, and drainage systems to ensure shelters remain habitable under emergency conditions. That means verifying air filtration, confirming seal integrity, and checking for moisture intrusion—issues that can escalate quickly in an enclosed, underground environment.

Even in properties built for everyday living below ground, the upkeep is significant.

“There's 12 air conditioning units. So imagine a building with 12 air conditioning units and the cost to maintain that,” Erker says of her underground listing. “It's just on a bigger scale, like any other large-scale home.”

Many homeowners underestimate that reality. A bunker functions less like a static piece of real estate and more like a boat or swimming pool—something that requires ongoing maintenance, specialized systems, and steady investment.

For buyers who see bunkers as long-term investments, the real math isn’t in the build cost but the upkeep. Construction may run six figures, but keeping it airtight, dry, and fully operational can turn ownership into a lifelong project—one sustained by the hope that it never actually needs to be used.