Missouri residents are at risk for one of nature’s most violent storm: Tornado. Tornadoes can cause fatalities and devastate an entire community in seconds. A tornado is a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground where winds can reach 300 miles per hour. St. Louis area tornadoes are seldom visible, with rain and nearby low-hanging clouds obscuring their presence. They can develop so rapidly that little warning is possible.
These windstorms pose a serious threat to buildings and occupants. Modern building codes provide for features such as simple “hurricane clips” that, when attached correctly, can help hold the roof down. Even if your building is “built to code” there’s no guarantee that it can withstand winds from tornadoes. A designated area in the home or building can be constructed to provide a space where you can seek refuge. These “safe rooms” can be built in a basement, atop of a concrete slab, or in a room on the main floor.
Safe rooms built below ground level provide the greatest protection, but a safe room built in a first-floor interior room also can provide the necessary protection. Below-ground safe rooms must be designed to avoid accumulating water during the heavy rains that often accompany severe storms.
Consider the following when building a safe room:
- The safe room must be adequately anchored to resist overturning and uplift.
- The walls, ceiling and door must withstand wind pressure and resist penetration by flying objects and falling debris.
- There must be positive connections between all parts of the safe room.
- Walls that are used as walls of the safe room must be separated from the structure so that damage to the building will not cause damage to the safe room.
The author has supported the owners and construction teams during safe room projects in these two buildings.
Additional information about safe rooms is available from FEMA and the ICC: