Shipping containers can make great storm shelters being economically available and inherently strong. However, there are multiple factors to consider like the local climatic conditions and whether the shelter is planned to be above ground or underground. Storage space for all survival supplies per person as well as cost considerations in reinforcement and weatherproofing need to be taken into account.
Why Shipping Containers are Suited for Storm Shelters
Shipping containers of weathering steel are made to withstand heavy rains, snow and winds as fast as 150 miles per hour. Although these are robust structures, one must still check what other modifications are needed to convert the container into a storm shelter. This could depend on your local climate conditions: Are tornadoes common in your area? Is there heavy flooding?
It also depends on whether you plan on having an above-ground or underground shelter.
An underground shelter would require additional reinforcement inside and outside as the container is strong at its four corners, allowing them to stack easily. Burying them underground means there is applied and heavy pressure pushing on its surface walls and sides. Seeing as even the roof needs heavy reinforcement from the earth, this is a more costly option. (1)
You’ll also need to ensure your container still gets ample ventilation, to prevent moisture build up and damage. Unattended, this can lead to mold and eventual health risks in your respiratory system. A quick fix could be buying some silica bead (“do not eat”) pouches to absorb the moisture. A sustainable way is having vents along the walls, all covered with mesh guards to protect from anything else coming in. (2, 3)
Above-ground container shelters are easier to construct without having to worry about ventilating for moisture build up. They also require less maintenance and have easier egress, as you wouldn’t need a ground entrance with stairs leading to the underground bunker. The difficulty here will be properly anchoring the unit to the ground. Tie-downs, anchors and steel cables are often secured to a concrete foundation to ensure your container doesn’t blow away. (1)
As foundation systems are expensive, ensure they are equipped to withstand not only heavy storms but flooding and any other earth movement. (2)
Weathering steel or “Corten Steel” is designed to be rust-resistant in its combination of steel alloys and rust-resistant paint. The doors are usually built to seal wind and watertight. Ensure both these qualities are still intact in your unit to make for a fantastic storm shelter.
Being airtight is a great quality that containers have to protect you against strong winds, tornados, dust inhalation and any airborne viruses. These contain the air so well that nothing comes in or leaks out. (4)
Whether above ground or underground shelter, it pays to reinforce the container further with cross members and diagonal members. This adds to its structural strength against strong winds and debris.
Make sure all glazing like your windows are impact resistant. Opt for metal doors or have storm shutters on all openings to further protect from any hazardous flying debris.(3)
How to Prepare your Container as a Shelter
Remember containers come in only a couple of standard sizes. This means that for each 20 foot container, you only have less than 160 square feet (or 14.8 square meters) to fill up with all your living essentials. Remember you need to consider how many people it needs to shelter, how many supplies for each person and how long. (2)
This can be food, water, blankets, flash lights, a first aid kit and any special medicines. It may also include toiletries and other items to maintain the sanity while waiting inside the container.
The recommended duration one must prepare and stock up for can range from three days to two weeks as the minimum that Red Cross recommends. (4). Some would recommend preparing up to a month. (5)
If after all this computation your shelter seems too small, the great thing about containers is that they are stackable and therefore expandable in floor area.
Whether above ground or underneath, fitting your container with LED lights is a great idea as these last longer and emit less heat than regular light bulbs. This lessens the cooling needed indoors and reduces any accidental burns.
As most containers only come with one set of doors, the most important consideration for your container as a storm shelter, or shelter of any kind is to provide a second door of exit. All shelters are required two points of egress in case of an emergency and one exit accidentally gets blocked. It is recommended these two exits are farthest from each other at opposite ends if possible. This can also be a roof hatch or large enough window for a person to easily escape. (2)
Another thing to note is that the standard doors of containers lock from the outside. If possible, have this modified to lock from the inside with all doors swinging out or toward the direction of egress.
Other Key Survival Points to Factor
When we’ve secured the fundamentals, you can go into the details for comfort. Ensure your heating, ventilation and air conditioning (HVAC) are equipped to give you the cleanest air. Air filters like the pandemic made famous HEPA filters and UV lights help disinfect and rid of any bacteria. If you have an architect or building professional helping you, ask to have a positive pressure system designed, that will serve as a natural airlock for your container. (5)
For longer periods of survival, you may have to secure a generator with fuel storage for electricity if you plan for any cooking and heating. Note that these need to be carefully planned as well to prevent in-house fires or harmful gas exhausts.
Also consider your waste system from human waste to house trash and the proper disposal of these.
Lastly but highly important is to consider your personal comfort. Whether that’s in your bedding, clothes, some entertainment or even comfort food to help pass the calamity.
If sheltering any people of older ages, babies or those with limited accessibility, these also need to be factored into your design and allocated supplies. Your fur babies and pets will also need their own set of supplies. Think of any disabilities, food or medical allergies that may entail more supplies and storage.(4)
Take Key Tips from the Pros
If you’re lucky, some companies in your area may specialize in creating bunkers, eliminating all the renovation needed on your container. Found a manufacturer that ships to you? You can compare it to the specifications listed here, that have aimed to solve the problems containers have as previously mentioned. Shipping Containers Make Terrible Shelters – Rising S Company (risingsbunkers.com)
Other companies that specialize in storm shelters are Stormbox, which engineers shipping containers to withstand F5 tornadoes and Category 5 hurricanes as well as Henson Construction, whose “safe zones” are multipurpose shelters. (4)
And if you’re serious about building up a doomsday shelter bunker, I recommend this comprehensive piece by Discover Containers: Shipping Container Bunkers and Emergency Shelters – Discover Containers
References:
- Michelle of Transocean. (2022, March 10). Why shipping containers make great storm bunkers: Transocean. Transocean Equipment Management. Retrieved August 2022, from https://www.transoceancontainers.net/why-shipping-containers-make-great-storm-bunkers/
- Cam Bob. (2021, November 1). Your guide to shipping container storm shelters. Mobile Modular Portable Storage. Retrieved August 2022, from https://www.mobilemodularcontainers.com/blog/shipping-container-storm-shelters
- SEO Partner. (2022, May 10). Can you turn a shipping container into a storm shelter? Can You Turn a Shipping Container into a Storm Shelter? Retrieved August 2022, from https://www.atlanticstorageco.com/can-you-turn-a-shipping-container-into-a-storm-shelter
- Discover Containers. (2021, October 1). Shipping container bunkers and emergency shelters. Discover Containers. Retrieved August 2022, from https://www.discovercontainers.com/container-bunkers-shelters/
- Filho, A. F. (2018, January 1). Things to consider when building storm shelters out of shipping containers. Western Shelter. Retrieved August 2022, from https://westernshelter.com/blog/2020/12/29/building-storm-shelters-out-of-shipping-containers
