What Causes Structural Damage During a Tornado?

The primary cause of structural failure is the immense wind force. Tornadic winds rotate at high speeds, creating dramatic pressure differences between the inside and outside of a building. This pressure imbalance pushes and pulls on walls, windows, and roofs with overwhelming force. If the structure cannot withstand these loads, it can be ripped apart or collapse entirely.

Winds can also cause damage through uplift. The same aerodynamic principles that lift an airplane wing apply to your roof. When wind flows rapidly over a roof, it creates a low-pressure area above it. This can literally suck the roofing materials upward, breaking their connection to the walls and allowing the entire structure to be compromised from the top down.

A building's foundation and frame are subjected to complex, shifting stresses. The twisting motion of a tornado applies torque to the structure, which it is not designed to handle. This can cause the frame to rack or twist, pulling it away from its anchor bolts in the foundation. Once this connection fails, the entire building becomes unstable and can slide or collapse.

Even if the main structure remains, the foundation can shift or crack. Water intrusion from torrential rain often accompanies tornadoes, which can saturate the soil. This saturated ground provides less support, allowing the foundation to settle unevenly or heave. Such movement cracks walls and disrupts the structural integrity, making the building unsafe long after the storm has passed.

Your first priority is safety. Do not re-enter a damaged structure until authorities deem it safe. Visually assess the damage from a distance, looking for hazards like downed power lines, gas leaks, or unstable walls. If you must enter briefly for essential items, wear sturdy shoes, gloves, and protective clothing to avoid injury from sharp debris.

Contact local water damage pros for a thorough inspection. They can assess the water intrusion and structural stability, then begin emergency services like water extraction and structural drying. You should also contact your insurance company to start the claims process. Policies vary, and your insurer decides what is covered. Document all damage with photos and videos before any cleanup begins.

• Secure the property from further weather and unauthorized entry if safe to do so.
• Turn off the main electrical power and gas supply at the meter if you suspect damage.
• Avoid using electrical appliances or outlets that may have gotten wet.
• Remove undamaged valuables and important documents to a dry, safe location.
• Discard any food, beverages, or medicines that were exposed to floodwater or debris.
• Keep a detailed list of all damaged or destroyed items for your insurance claim.