Living in any place where storms are commonplace can be a headache, especially in places like the Tornado Alley states or seaside towns. Tornadoes, in particular, don’t need an introduction to how destructive they can be, making a DIY storm shelter a necessity in many places.
Made from shipping containers, this shelter can be a worthwhile solution to counter these weather phenomena. Shipping container buildings have proven to be durable and flexible establishments, so why can’t we turn them into storm shelters?
So, how can we build a DIY storm shelter from shipping containers? Let’s see how below!
Also Read: Container Pools and How to Clean Them with the Best Practices
Why Storm Shelters from 20ft Shipping Containers Are Perfect for Most Places
Unmatched Strength and Durability
As we know, 20 shipping containers are built from Corten steel (ASTM A588), a corrosion-resistant alloy designed to endure harsh marine environments.
When anchored properly, their walls (1.5–2.0 mm thick) and reinforced corner posts (6–8 mm) withstand wind speeds up to 120 mph.
Unlike traditional storm shelters, which rely on thin metal or concrete, containers offer structural integrity that resists flying debris and crushing forces.
If anything, reinforced containers survived simulated tornado winds of 250 mph and impacts from 15 lb debris traveling at 100 mph.
Even further, their rigid frames also support vertical stacking loads of up to 216,000 lbs, making them ideal for multi-story shelters.
Modularity and Portability
Weighing just 5,000 lbs empty, 20ft containers are easy to transport with flatbed trucks or cranes. In fact, you can place shipping containers as a DIY storm shelter in almost any place:
- Urban backyards: Partially buried or anchored above ground.
- Coastal areas: Elevated on helical piers to avoid storm surges.
- Rural farms: Buried underground with berms for added stability.
The container’s modular design also allows for future expansion. For example, stacking two containers vertically creates a two-story shelter, while joining multiple units horizontally accommodates larger groups.
Compliance with Safety Standards
Any properly modified container meets FEMA P-361 and ICC 500 guidelines for storm shelters. In case you’re not familiar with these guidelines, legitimate shipping containers have certifications for the following:
- Continuous Load Path: Ensures wind forces are distributed from the roof to the foundation (as emphasized in FEMA guidelines).
- Debris Impact Resistance: Reinforced walls and doors withstand 15 lb 2×4 lumber traveling at 100 mph.
- Anchoring Systems: Meet ASTM D3957 standards to resist uplift forces during hurricanes.
Types of Container-Based Storm Shelters
Almost similar to shipping container swimming pools, you can have several options on where to install your container DIY storm shelter.
However, these options have some benefits and drawbacks inherent in them:
Above-Ground Storm Shelters
Pros:
- Quick Installation: No excavation is required; shelters can be operational in under 10 days.
- Flood Avoidance: Elevated placement reduces flood risk.
- Easy Access: Ideal for elderly or disabled occupants.
Cons:
- Wind Vulnerability: Unanchored units may tip in EF4+ tornadoes.
Modifications:
- Anchoring: Weld containers to a 6-inch concrete slab with rebar and hurricane straps.
- Debris Deflection: Install sloped roofs made of 14-gauge steel angled at 30° to redirect flying objects.
- Shutters: Add steel shutters over windows and vents.
While this shelter type’s performance decreases for EF4+ tornadoes and above categories, this shelter can still work in most situations.
Underground Storm Shelters (Bunkers)
Pros:
- Enhanced Protection: Earth insulation shields against EF5 tornadoes and Category 5 hurricanes.
- Thermal Stability: Maintains temperatures between 50–70°F year-round.
Cons:
- High Costs: Excavation, waterproofing, and reinforcement add $8,000–$15,000 to the budget.
- Flood Risks: Requires sump pumps and French drains in high-water-table areas.
Modifications:
- Reinforcement: Weld 3/16-inch steel plates to walls and roofs to handle soil pressure.
- Waterproofing: Apply bitumen coating or rubberized sealant.
- Ventilation: Install solar-powered vents with HEPA filters to prevent CO2 buildup.
Although the more extensive work in excavating and waterproofing the shelter site may take more time, it’s worth the effort to build an effective shelter.
Hybrid Shelters (Partially Buried)
Pros:
- Balanced Cost/Protection: Combines underground stability with above-ground accessibility.
- Natural Insulation: Earth berms reduce heating/cooling costs by 30%.
Cons:
- Complex Grading: Requires precise landscaping to prevent soil erosion.
Modifications:
- Partial Burial: Bury the lower 4–6 feet and reinforce exposed walls with shotcrete.
- Berms: Build earthen slopes around the perimeter using geogrid-reinforced soil.
Benefits of Using Shipping Containers as Storm Shelters
The benefits of using shipping containers to build a DIY storm shelter are almost the same as enjoying the benefits of building a container home or office.
Superior Durability
Corten steel’s self-healing patina layer resists rust, while the container’s rigid frame withstands impacts from fallen trees or vehicles.
Rapid Deployment
Unlike traditional shelters, which take weeks to build, a modified container can be ready in under 10 days.
Eco-Friendliness
Repurposing used containers reduces landfill waste. A single 20ft container saves 3,500 kg of CO2 compared to new steel production.
Multi-Purpose Use
When unused, you can use the shelter as storage for tools, emergency supplies, or seasonal items if you don’t have an extra storage room in your home.
Customizable Design
- Insulation: Line walls with closed-cell spray foam (R-6.5 per inch) or mineral wool.
- Energy Systems: Add solar panels and lithium batteries for off-grid power.
- Comfort: Install portable AC units or wood stoves.
How to Build Storm Shelters from 20’ Shipping Containers
At this point, we’ve understood the benefits of building a DIY storm shelter from shipping containers. Now, all we need to do is construct the shelter.
Select and Inspect the Container
To start the construction process, choose a Cargo-Worthy (CW) container that has no dents, rust, or compromised CSC plates.
While choosing the right unit, ensure the container’s doors seal tightly and the floors are free of rot.
Secure Permits and Plan the Site
Like constructing any building, you must verify local regulations (e.g., setback requirements, floodplain restrictions) on building storm shelters.
Soil testing for the shelter is also important, so be sure to conduct percolation tests to assess drainage for underground shelters.
Prepare the Foundation
There are some differences in setting up the shelter based on its type, which you can read below:
- Above-Ground: Pour a 6-inch concrete slab with rebar grid and anchor bolts.
- Underground: Excavate a hole 2 feet wider than the container and line it with gravel.
Reinforce the Structure
Once you’ve built the shelter’s foundation add 4×4-inch welded steel beams to walls and roofs to support the shelter properly during storms.
Furthermore, you can do cross-bracing by installing diagonal braces at corners to prevent twisting.
Weatherproof and Insulate
When setting up the shelter’s roof, you can apply an elastomeric coating to reflect UV rays if you’re building an above-ground shelter.
Regardless of which shelter type you build, use closed-cell spray foam for walls and radiant barrier foil for ceilings as insulative layers.
Install Ventilation and Utilities
Ventilation and utilities can keep anyone inside the shelter comfortable during major storms. Because of that, install the following in the shelter:
- Airflow: Add whirlybird vents or solar-powered fans.
- Electricity: Run 12-gauge wiring in conduit and install GFCI outlets.
Secure Entry Points
Lastly, replace standard doors with steel bullet-resistant models in the container shelter so the storm or tornado won’t shake off the cargo doors.
Installing dual deadbolts and hinge pins is also important to deter forced entry by unwanted parties into the shelter.
What to Put Inside the Container Storm Shelter
And so, the DIY storm shelter is finished and ready for use. Nice! But, the shelter is still barebones and can’t function as a proper shelter.
Because of that, what are the things we can put inside to make it a proper storm shelter?
Survival Essentials
- Water: 1 gallon/person/day (3-day supply minimum) in BPA-free containers.
- Food: Stock 2,000 calories/person/day of non-perishables.
- First Aid: Include trauma kits and prescription medications.
Tools and Safety Gear
- Multi-Tool: Multi-tools you can use for repairs and other emergencies.
- Fire Extinguisher: Fire extinguishers that can handle Class A/B/C fires.
- Communication: Hand-crank radio with NOAA alerts.
Comfort and Sanitation
- Lighting: LED strips with USB power banks.
- Sleeping: Inflatable mats and mylar blankets.
- Sanitation: Portable toilet with waste bags.
Long-Term Preparedness
- Documents: Waterproof safe for IDs, insurance papers, and cash.
- Seeds: Non-GMO heirloom seeds for post-disaster gardening.
Common Mistakes to Avoid
While these mistakes can seem trivial and negligible, they can make the shelter not function as it should during storms. Because of that, do the following:
Skipping Soil Testing
Soft soil or high water tables can collapse underground shelters. Conduct geotechnical surveys before excavation.
Neglecting Ventilation
Poor airflow leads to CO2 poisoning, so install dual vents with mesh screens.
Using Substandard Anchors
Cheap container anchors fail under stress, so be sure to use ASTM-certified hurricane straps and epoxy bolts.
Also Read: Shipping Container Security: How Secure is the Platform?
Conclusion
Considering the strength of shipping containers, it’s no wonder many people start using shipping containers as building blocks for a DIY storm shelter. To meet that need, trust Tradecorp to supply such shipping containers to build the strongest and most effective storm shelter out there. Contact us today and we’ll respond ASAP!
