Tornado Safe Room

Every year there are over 170 “Tornado Days” in the United States that yield over 800 tornadoes. On average more than 20 of these tornadoes are labeled as “killers” claiming more than 90 lives per annum. A safe room or storm shelter is the best defense against such disasters.

Traditionally, storm shelters are built into the ground outside a home. The flaw in this logic is that most people who are killed by tornadoes actually die from flying debris. This would indicate that staying within a dwelling is safer than leaving, even if there is a shelter outside. Based on this knowledge, FEMA (Federal Emergency Management Agency) has created a series of downloadable plans that can be accessed from their website. Many homeowners can retrofit these designs into their existing homes, and many builders can easily implement any of these designs into the construction of a new home. Besides these plans, there are a number of companies that offer in-home shelters construction out of materials that range from steel to fiberglass to bulletproof plastic.

To construct a safe room according to the FEMA drawing AG-4 (Steel and Plywood) you’ll need:

    * Enough 3/4" plywood to cover the walls and ceiling of the chosen room 3 times (2 layers on the exterior, 1 layer on the interior).
    * Enough 14-gauge sheet steel to cover the walls and ceiling.
    * 1/2" anchor bolts to be placed along the bottom plate every 32".
    * Anchor straps to hold the studs to the bottom plate.
    * "Doubled up” 2x4s around the entire structure.

1. Whether retrofitting this design into an existing, identifying the proper location for the structure is crucial. An ideal location would be a small room or closet (large enough to holder your family and supplies) that is located on the ground floor, away from all exterior walls. Even though the walls of the safe room will stop flying debris, it is best to have as many layer of solid material between the safe room and the exterior of the home. A closet underneath a staircase is an ideal choice. The strength of the stair stringers offer additional support.

2. Once the studs have been doubled up and the bottom plate has been anchored and strapped, attach the sheet steel to the studs. Due to the heavy gauge it will be necessary to drill pilot holes for all the fasteners.

3. Once the steel has been attached, two layers of 3/4" plywood will be attached on the outside of all the walls. Then a single layer of 3/4" plywood will be attached to all interior walls.

4. After the completion of the plywood attachment, drywalling can proceed as normal.

Supplies to keep in the shelter:

    * A first aid kit
    * A two-way radio or cellular phone
    * Fresh drinking water
    * Food, enough for a brief stay (Nuts, Energy bars, etc)
    * Blankets
    * A weather radio
    * A conventional radio
    * An empty 5-gallon bucket with a lid (it will make sense when the time comes)

FEMA Publication
TAKING SHELTER FROM THE STORM: Building a Safe Room Inside Your House