Oklahoma City

Tornado Shelter

Tornadoes and storms are a very common phenomenon in the United States and almost every year thousands of people suffer from its consequences. In such circumstances building a tornado shelter no longer seems like a weird thing to do and plan. More and more families spend time and resources preparing a special shelter or safe room to be able to protect their family and themselves. It is a time-consuming task, but it’s worth it.

There are many things to consider before you actually start building the shelter. In fact, you’ll have to spend equal time gathering material and information, and building the actual shelter. The more time you spend on the research and consultation with professionals, the better you’ll be prepared when the actual building begins. We also highly advise you to consult with the FEMA documentation, found on their website.

Big storm shelter

The ‘Taking shelter from the storm’ is a booklet you must be acquainted with before you start building and gathering material. Not only that, but FEMA has set some strict regulations about the requirements for building a shelter. You can find these requirements again in the document mentioned above, the so-called FEMA 320.
Start the preparation for building the shelter

The next most important thing, after you’ve read the FEMA requirements, you have to obtain a construction permit. The National Performance Criteria for Tornado Shelters has set some criteria you absolutely must follow to ensure the shelter provides full security and protection.

This means that you’ll need this permit, including advice from a professional builder or architect. They have to inspect the area, soil and conditions in order to determine how the shelter can be built for optimal protection. In case you want to use the FEMA 320 guidelines, your plans need to be first approved by the National Performance Criteria.

Moving on, you need to also assess the wind zone. This means that you have to determine the wind’s direction. There are usual currents and you have to determine from which direction the wind (and potentially a tornado) would come. This will be a good guideline about how sturdy and reliable the shelter must be built. So, you can check a wind zone map in order to determine these details. FEMA also provide useful information in this regard.

Next you have to determine and decide where to build the shelter. Should it be in the basement, inside the house, attached to the house or should it be a completely separate building in your backyard? The decision you make may be based on your financial status or your personal preference. Usually tornado shelters built under the house may require some retrofitting of the house and may be more costly. If you want to build a shelter, without changing the house’s construction, this may be the cheapest way.

Tornado shelter outside house

Building a separate construction some 150 feet from the house (no further than 150 feet) can also be a more economical approach. The only problem is that you would be exposed to potentially strong winds, which may endanger your life, as you try to reach the outside shelter. That’s why is important to learn about safety regulations while battling a tornado, like the ones we described here.

An attachment to the house is also a great way to cheaply and economically build a tornado shelter.
Building process

To begin with, you need to first gather your material. You need metal frames, lots of concrete for building the walls, roof and floor, and various tools for the actual building.

Start off with digging the hole first. You’ll need to dig it a bit larger than initially planned, so that you have room enough to maneuver inside the hole. Also, consider that a tornado shelter doesn’t have to be large (like a storm shelter), since tornadoes don’t last long and you can spend an hour or so inside, without access to bathroom, kitchen, etc. Of course, building a tornado shelter means you have to prepare some room for safety and emergency kits, including a first-aid kit; they are a-must in case anyone got injured.

Digging a hole for storm shelter

So, to measure the shelter, you can count 3 square feet per person. Judging by this you can determine the size of the entire shelter. Count another 1 square foot for the emergency kits and you’ll have the total size for the shelter. Use the FEMA documentation and design plans for determining how to use the given space in an optimal way.

Before you start building and laying the floor you have to first drill holes through the ground floor of your house. As you prepare the floor, and you lay the concrete shelter floor, keep bolts into the floor. Ideally, you may have to make anchors separately first. Make them using metal frame and pouring concrete into blocks to keep the anchors stable and solid. Then you can attach the shelter floor to it. Otherwise, proceed to laying the floor.

You need to use concrete for the floor and you need to make it thick, about 5 inches at least, so that it holds firmly in place. If you’re building the shelter immediately in contact with soil, you’ll have to first level the ground, before you pour the concrete. If you’re building inside your house, you don’t have to do that, since the floor is already flat. If the tornado shelter is meant as an outside attachment to the house, then you’ll also have to be sure to level the ground before you continue building.

You’re ready to pour the concrete. The amount must be calculated properly according to the overall size for the shelter and by taking into account that the thickness should be about 5 inches. As you’ve done that, lay the floor and wait for it to dry. This may take up to a week.

During that time, it’s advisable (but not crucial) to pour water over the drying concrete and always keep it wet. This will protect the concrete from cracking during the drying process and many professionals use this practice in their work. And since concrete is like a sponge, it absorbs a lot of water and moisture, so you’ll have to keep it wet almost all the time. Make sure, if you’re building inside your house, to keep the room well ventilated so that no mold gathers. If that happens, wash it and repaint the walls or roof where it gathered.