How to Build a DIY Underground Bunker and Survive SHTF

Nuclear fallout. The Black Death 2.0. A horde of hungry zombies clambering for your supplies.

You know what can protect you from all three? An underground bunker.

Underground bunkers (sometimes called bomb shelters, fallout shelters, or survival bunkers) are fool-proof ways to survive an apocalypse or two. But they don’t come easy; in fact, it takes a lot of effort, planning, and money to build underground bunkers.

Curious about how to make a DIY underground bunker that can put your old man’s Cold War bunker to shame? Read on:

A Brief History of Underground Bunkers

Humans have had a long history with subterranean dwellings, but the first “real” tactical bunkers were used back in World War 1. Most of these were located all over Europe and were used to house artillery and supplies.

After World War 2 and during the Cold War, underground bunkers were constructed as protection against possible nuclear attacks or fallouts. These structures had three things in common: they were underground, they were permanent, and they were, for the most part, indestructible.

Today, you can see many of these bunkers still existing around the world. British folks have their Anderson Shelters, which they built in their backyards during the Blitz. If you’ve ever been in Tornado Alley, you’ve probably seen one or two tornado bunkers. Heck, even China has a network of Cold War bunkers that they’ve now turned into cramped residential units.

Why You Should Get an Underground Bunker

Underground shelters have endured long bouts of war and peacetime, and for good reason: they’re built for survival. These shelters can protect you against a variety of natural or man-made threats.

Should you get a bunker for yourself? Here are a few reasons you might consider getting one:

Protection from nuclear weapons and fallout

It’s been decades since the Cold War, but the threat of nuclear warfare still looms over everyone like a giant shadow. Countries like North Korea, Russia, and China have access to hundreds of nuclear weapons that they can launch whenever they please.

And if you think international law like the NPT (Nuclear Non-Proliferation Treaty) can shield you from nuclear warheads blasting you to kingdom come, you’re sorely mistaken. And ignorant to boot.

One of the few ways to survive a nuclear war and the inevitable fallout would be to stay in an underground bunker. Underground shelters are built to survive nuclear explosions, block radiation, and withstand the subsequent shockwave.

Hideout during war and civil unrest

If you’re unable to bug out, the next best option would be to hide in plain sight. Underground shelters built under unassuming backyards help you hide from looters and the zombie horde. It also protects you from a disease outbreak or biological warfare.

Protection from severe weather

The US experiences more tornadoes than any other country in the world, averaging about 1,200 tornadoes each year. And no, Dorothy, these don’t just happen in Kansas or Oklahoma. Tornadoes and severe weather can occur anywhere in the United States, so if you’re in their direct path, you might want to consider getting your own storm cellar or building a DIY underground bunker.

Extra storage space

If nothing else, underground bunkers make for excellent storage spaces. The temperature and humidity levels in underground shelters remain constant, protecting your food stash from spoilage. The absence of heat and direct sunlight also helps extend your supplies’ shelf life. As long as you keep it dry and clean, you wouldn’t have to worry about vermin and pests.

Should You Buy or Build a DIY Underground Bunker?

If you’ve got extra cash lying around, you might want to consider buying a ready-made underground bunker. These range from economy-sized bunkers with basic necessities like air filtration systems, beds, shelves, and plumbing to sprawling underground mansions complete with swimming pools.

There are companies out there who will evaluate the site, custom-build, or provide ready-made underground shelters that will fit your needs. These types of shelters usually cost around 50 grand at the minimum.

The excavation is another expense—this will cost you around $5000 upwards, depending on the size of the shelter and where you’re located. Obtaining permits to install the bunker is usually not included in the quote.

If you don’t have any space to spare, you can buy a spot in one of the underground survival communities that have sprouted left and right in recent years.

Vivos, a company based in California, owns numerous bunker communities across the country and calls its network of underground shelters “the backup plan for humanity.”

The company recently acquired a former military base in South Dakota and repurposed all 575 underground bunkers found in the base into survival shelters. Each bunker in this community is worth $35,000 (plus yearly and monthly dues) and is equipped to house up to a couple dozen people.

If buying modular or ready-made shelters isn’t up your alley, you can always make a DIY underground bunker. A word of warning though: this ain’t some backyard fort.

Are we going to teach you how to build it, though? Hell yes.

Below you’ll find factors you need to consider when building your own underground shelter:

Factors to Consider in Building a DIY Underground Bunker

Deciding to build a DIY underground bunker is like investing in another house altogether, so you can’t do it on the fly. However, if the idea of having your own bunker excites you, here are some of the things you should consider:


Why are you building a bunker in the first place?

Is it for an impending nuclear war and the following fallout? Is your area at risk of an airstrike? Are you preparing for a long-term disaster or just need a space to protect you from severe weather?

Your bunker’s purpose will ultimately determine all the other factors that follow, so think about it.


Location is another crucial factor to consider when you want to build underground bunkers. It must have access to resources but must be relatively far from discovery. Ask yourself the following questions:

  • Can you build right in your backyard, or are your nosy neighbors such a huge risk that you have to build it in a more low-key location?
  • If so, how accessible is it? Can you get there by foot, or do you need transportation?
  • Is the terrain and soil condition ideal to support your bunker?
  • Does your location have natural gas pockets?
  • How deep or shallow is the water table?

Bunker size

How big is your DIY underground bunker going to be? How deep do you need to dig? Its size will primarily depend on your land area, but you should also consider the number of people occupying the bunker, the duration of your stay, the type of supplies you’ll be storing, and the overall bunker design.

Floor Plan and Layout

An efficient floor plan and layout are essential for your underground bunker. This should include entrance and exit points, living spaces, storage spaces, mission spaces for communication, plus important components like air and water filtration systems.

There are dozens of available bunker floor plans online, which you can download or replicate for your own DIY underground bunker. You can also make your own floor plan and customize it according to your needs. What rooms and facilities will you include in your underground bunker? How will you manage the limited space?


How much are you willing to spend for your underground bunker? The bigger your budget, the faster you can get the project done.

Still, even if you don’t have a lot of extra cash lying around, we don’t recommend that you pinch pennies when it comes to your DIY underground bunker.

Don’t go buying cheap materials, winging your own ventilation system, or opting not to hire a contractor even if you sorely need one. Unnecessarily cutting corners in the name of budgeting can bite you in the butt later along the way, so consider your budget seriously before breaking ground.

How to Build an Underground Bunker

Okay, so we’ve gotten the basics out the way. Let’s start making your DIY underground bunker.

Getting Your Permits

The first step to building your own underground shelter is the least exciting part of it all: getting your permits.

Permits vary depending on your state and county, and they’re boring as hell, but you gotta get them to ensure that you don’t alter the local geology or potentially cause floods in your area.

You should also call the utility company to make sure that you don’t hit any gas, water, or internet lines. You’ll be facing a hefty fine and the ire of your entire neighborhood, so be a trooper and just do it.

Secrecy should still be a priority, so if you’re not willing to disclose that you’re making a DIY underground bunker for the apocalypse, you can just say you’re building a wine cellar, digging a swimming pool, or installing a septic tank. You can even hire an out-of-town contractor further along the way to keep things on the down-low.

Prepare Your Floor Plan and Bunker Design

prepare your DIY underground bunker floor plan and design

As mentioned earlier, there are tons of bunker blueprints and layouts available all over the internet. Take a look at any of them and see what best suits you. The important thing is to cover all the crucial bases like:

  • Viable exit and entrance points
  • Living spaces
  • Ventilation and exhaust systems
  • Drainage and sewage systems
  • Light and temperature control

You should also consider the design of your DIY underground bunker. You can choose from the popular round culvert pipe bunkers or go for the traditional, concrete-and-steel-plated square design. Each has their own pros and cons, so weigh those out carefully.

Regardless, most fallout shelters have L-shaped entrances to protect their inhabitants from gamma rays. Airtight inner doors are also the standard to keep noxious gases away and to make sure that the NBC filtration system works properly. Your doors also protect you from debris, fallout, radiation, and intruders, so make sure they’re strong. Preferably, they should be constructed from a steel frame and wood.

If you want to stay extra safe, you can construct your hatches from thick, hardened A500 steel, which are impervious to abrasions and bullets. Plus, it makes for a really badass entrance to the rest of the bunker.


Concrete is literally a solid choice for your DIY underground bunker. It’s strong yet relatively affordable, plus it’s easy to work with. Combine it with steel, and you have a safe and sturdy underground dwelling.

Bricks are also a good option for your bunker walls, but you also have to consider that they take some time to lay down. We don’t recommend building your own underground shelter entirely out of wood because of an itty bitty issue called decomposition. But you can incorporate hardwood in some aspects of your DIY underground bunker, as in the floors and finishings.

Get Digging and Building

A depth of at least 6 feet is needed for most underground bunkers, but of course, this would still depend on the scale of your shelter.

If efficiency is your top priority, you’d need to rent heavy-duty machinery to excavate the site. You might also want to hire a contractor to help you do most of the heavy lifting and installations.

If you’ve got some spare time, you can also dig it the old-school way with a shovel. It takes a while and can be difficult when you encounter huge boulders, but it’s a cheap (albeit time-consuming) way to get things done.

Ventilation and Air Filtration

You need to find a way to filter clean air into your DIY underground bunker. Installing an NBC (Nuclear, Biological, Chemical) Air filtration system is a must. This system sucks air from the outside and filters 99% of impurities like dust, bacteria, and other contaminants. NBC systems run on power, but they can be set up to automatically switch to backup battery juice, too.

While you’re at it, make sure to keep humidity levels low to keep your DIY underground bunker dry, free from molds, and intact for many years to come.

Secure Your Water System

man making adjustments to water pressure

You can’t survive without clean water, so it’s important to secure a reliable water system. Depending on how long you plan on staying in your bunker, this could range from storing gallons of water for your family until the threat passes to setting up long-term water acquisition and filtration systems.

For short-term bug-in situations, the standard is to store 2 gallons of water per person per day. For long-haul situations, it’s always best to have an underground water tank for a clean water supply.

You can also try to dig a well if your location and resources permit, or use gravity to supply water to your DIY underground bunker. Rainwater harvest systems are usually viable in most survival situations, but you don’t want to rely on them in case of a nuclear fallout situation.

Whichever system you choose, make sure to have a solid water filtration and purification process in place. A water system with a UV lamp allows you to purify large amounts of water at a time, but it doesn’t hurt to have backup plans like water purification tablets or iodine drops, too.

Waste Disposal System

Like your water supply, your waste disposal system can go two ways: you either can go full-on bucket brigade, or you can install a more elaborate waste disposal system as in a septic tank or a composting toilet.

We don’t recommend using buckets or paint cans as makeshift toilets, but if you’re going to go that way, make sure that they’re tightly sealed by lid or a sheet of plastic. You also have to ensure that they’re sturdy and won’t leak. Lastly, strategically place them near exhaust vents to help control the odor, or dig a waste disposal pit several feet away from your bunker.

The other options are less labor-intensive. You can include a septic tank to take care of your sewage and greywater. Composting toilets, on the other hand, work by evaporating waste material and turning them into compost. These systems are used in most off-grid homesteads and can work well for your bunker.

Squirrel Away a Solid Food and Supply Cache

Building a food cache for your bunker is similar to squirreling away supplies for your prepper pantry. Here’s an in-depth guide on how to do just that.

While you’re at it, don’t forget to load up on protection, ammo, communications systems, emergency light and heating, plus some books and games for entertainment.


Once your DIY underground bunker’s done, protect it from looters by hiding it in plain sight. Cover your bunker with several inches of soil to help ward off possible radiation.

Also, plan out how you’re going to conceal entrance and exit points from the outside world. Some have hidden entrances in their main house, others cover the hatch with debris, while some folks hide entrance and exit points in plain sight by building sheds or outhouses over the entrance points.

Final Thoughts

Once you’ve got all the components of your bunker figured out, it’s just a matter of building and installing them. Don’t have all your ducks in a row yet? No need to panic. A survival bunker is a long-term project and needs a couple of years to fully realize.

Building your own underground shelter is easier said than done, of course, but with patience and perseverance, you’ll have yourself a bunker that can protect your from the worst scenarios.

Already have a DIY underground bunker underway? What’s your biggest challenge so far? Let us know in the comments below!

Advertising and Affiliate Disclosure

We put a lot of effort into all of the content on We are able to provide this content for free because we earn money for advertisements on this site. We also earn small commissions for sales generated via our affiliate links. While these commissions do earn us income, they do not cost our readers anything additional. Clicking on our ads or links helps support our staff and we sincerely appreciate your support.