Guide to Building a Shipping Container Underground Bunker

Building a Shipping Container Underground Bunker

Key Takeaways

• Shipping container bunkers are cost-effective, with used containers available at a fraction of traditional building materials.
• Containers are durable and can withstand significant ground pressure when reinforced properly.
• Building a container bunker involves steps like site selection, design, and obtaining necessary permits.
• Avoid common mistakes like poor ventilation, insufficient waterproofing, and improper emergency exits.
• Conexwest can help by providing quality shipping containers and fabrication services.

Why Build a Shipping Container Underground Bunker

1. Cost-Effectiveness: Purchasing a used shipping container is often significantly cheaper than constructing a traditional concrete bunker.
2. Modularity and Customization: Shipping containers are inherently modular to allow for various modifications. This flexibility enables you to customize the bunker for different purposes, such as storage, living space, or emergency shelter.
3. Durability: Shipping containers can withstand harsh conditions at sea, which translates to a strong structure capable of withstanding ground pressure when buried. With proper reinforcement, they can serve as reliable underground shelters.
4. Quick Delivery and Setup: Containers can be easily transported to the desired location to facilitate a quicker setup compared to traditional construction methods.
5. Protection from Natural Disasters: A buried shipping container can provide significant protection against extreme weather events, such as tornadoes, hurricanes, and floods.
6. Security: An underground bunker can be hidden from view to provide a discreet location to store valuables or to seek refuge during civil unrest or other crises. This concealment adds an extra layer of security compared to above-ground structures.
7. Long-Term Storage: The ample space within a shipping container allows for the storage of essential supplies, food, and other items necessary for long-term survival.
8. Potential for Additional Features: With proper planning, a shipping container bunker can be equipped with essential amenities, such as ventilation, plumbing, and electrical systems, for added comfort and functionality during extended stays.

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Steps to Building a Shipping Container Underground Bunker

1. Purchase a Quality Shipping Container

Containers come in various sizes, usually ranging from 10ft to 45ft long. Assess your needs to determine the appropriate size for your bunker. Check that the container is structurally sound to withstand the pressures of being buried underground.

2. Reinforce the Container

Before burying the container, reinforce it to handle the weight of the earth and potential external pressure. This involves adding steel reinforcements to the roof and walls, as the corrugated steel is weaker on the sides. 

You can use rebar and cinder blocks to create a strong support structure. Additionally, consider burying the container upside down, as the thicker floor will then act as the roof to provide better structural integrity under pressure.

3. Waterproof and Paint the Container

To protect your bunker from corrosion and moisture, repaint and waterproof the shipping container. Specialized paints can also provide additional protection against environmental factors, such as radiation and chemical exposure.

4. Prepare the Site and Dig a Hole

Choose a suitable location for your bunker, ideally on higher ground to avoid flooding. Dig a hole that is larger than the container to allow for additional space for reinforcements and drainage. 

The depth of the hole should accommodate the container and any necessary foundation, typically around 7 to 10 feet deep, depending on how much of the container you want above the ground.

5. Install a Foundation

Lay a concrete foundation at the bottom of the hole to prevent the container from sinking and to provide stability. This foundation will also help with drainage so that water does not accumulate around the bunker. After setting the foundation, you can lower the container into the hole using a crane or specialized equipment.

6. Create Access Points

Modify the container's entry points for safe and easy access. If the container is buried, the original doors may not function properly. Instead, create an inward-opening door that can be accessed from inside the bunker. Consider adding a backup exit for emergencies.

7. Ventilation and Utilities

Louvered vent is the simplest way to ventilate a container

Install ventilation systems for a continuous supply of fresh air within the bunker. This can include air vents or a container ventilator, which should be discreet to maintain secrecy. Additionally, plan for utilities such as water and power by installing necessary piping and wiring connected to external sources like generators or water tanks.

8. Reinforce the Roof and Cover

Once the container is in place, reinforce the roof with additional rebar and cover it with at least six inches of concrete to withstand the weight of the soil above. After the concrete sets, add topsoil and plant grass or other vegetation to blend the bunker into the surrounding landscape.

9. Finalize Interior Modifications

After the structure is complete, focus on interior modifications based on your intended use. This may include installing shelving, creating living spaces, adding a bathroom, or setting up a kitchen area.

10. Regular Maintenance and Safety Checks

Finally, conduct regular maintenance checks on the bunker for its integrity and safety. This includes inspecting for any signs of corrosion, checking ventilation systems, and making sure that emergency exits are functional. Having a plan in place for emergency scenarios will improve the bunker’s effectiveness as a haven.

Common Mistakes When Building a Shipping Container Underground Bunker

Spray foam insulation is a go-to way to efficiently improve the energy efficiency of a container

1. Poor Site Selection: Choosing a location that is prone to flooding or unstable soil can jeopardize the integrity of the bunker. Select a high, stable area and avoid sites with poor drainage to prevent water accumulation around the container.
2. Ignoring Insulation Needs: Shipping containers can become extremely hot or cold depending on the weather. Failing to insulate the container properly can lead to uncomfortable living conditions and condensation issues. Use appropriate insulation materials to regulate temperature and prevent moisture buildup.
3. Ignoring Local Building Codes: Not checking local regulations and building codes can result in legal issues or unsafe structures. Always consult local authorities before starting construction.
4. Neglecting Corrosion Prevention: Shipping containers are susceptible to rust, especially when buried. Failing to treat the container with anti-corrosion paint or coatings can lead to deterioration over time. Use waterproofing and protective coatings to extend the life of the bunker.

How Conexwest Can Help You Build a Shipping Container Underground Bunker

Container Selection

We provide a wide range of high-quality shipping containers with sizes ranging from 10ft to 45ft in length. Our containers are inspected and certified so that you receive a reliable structure for your bunker.

Custom Modifications

From reinforced structures to ventilation systems, we can modify your container to make it suitable for your project. 

Expert Guidance

Our experienced team can provide guidance and support throughout the process. We can help you with site selection, design, and obtaining necessary permits. Our goal is to make the process as smooth as possible for you.

If you are ready, click the link below to discuss your requirements and get a quote.

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Frequently Asked Questions (FAQs)

How deep should the bunker be buried?

The depth at which you bury your bunker depends on several factors, including the type of soil and the intended use of the bunker. Generally, a depth of 7-10 feet is recommended for adequate protection from weather and potential threats.

What permits are required for construction?

Permits for building an underground bunker vary by location. Typically, you will need permits for excavation, construction, and electrical work. Check with your local building department to determine the requirements in your area.

Can I install a shipping container bunker myself?

While it is possible to install a shipping container bunker yourself, it is not recommended unless you have a good grasp of construction, welding, and excavation techniques. Improper installation can compromise the safety and functionality of the bunker. It is generally advisable to work with experienced professionals.

Is it safe to live in a shipping container bunker?

Yes, a properly reinforced shipping container bunker can be safe to live in. However, safety depends on adequate ventilation, insulation, and structural integrity. You should check that the container is free from toxic fumes, which can occur if the original coatings are not removed or if wooden flooring treated with chemicals is used. Regular maintenance is essential for ongoing safety.

How long does it take to receive my container from Conexwest after placing an order?

The delivery time for your shipping container will depend on your location and the availability of the container. Typically, we strive to deliver containers within 3-7 days after your order is confirmed. Please contact our sales team to learn more.