While hurricanes that trigger storm surges are better known for disastrous widespread flooding, a tornado can set the stage for severe water damage—one house at a time.
The first consequence of most tornadoes is rapid structural destruction. Here's how that sequence leads to water damage:
- In literally the first second of contact, circular forces created by the tornado vortex peel off roof shingles and sub-structure, break windows, implode doors.
- In just two more seconds, high velocity air blasting through busted windows and blown out doorways can inflate the house interior with enough pressure to lift the roof up off the wall structure and toss it aside.
- Now lacking windows, doors and perhaps even a roof, what's left of the house and whatever's inside is totally exposed to what usually happens next: water damage.
How Much Rainfall Occurs During A Tornado?
Little or none. The tornado itself is often a dry event as rain seldom falls in the strong updraft of the funnel cloud. However, a tornado is a phenomenon associated with large severe storms. Striking in the immediate wake of the twister, these extreme storms bring wind-driven torrential rain and hail, the factors that inflict severe water damage and secondary issues like mold contamination on the interior of damaged structures.
What Can Be Done To Reduce Water Damage Due To Tornadoes?
Unfortunately, a house that takes a direct hit from a tornado rated EF-4 with winds exceeding 165 miles per hour would have to be built to the standards of a concrete bomb shelter to resist structural damage that allows water intrusion. Even windows would have to be replaced with the equivalent of bulletproof glass, a very expensive proposition.
Certain measures utilized to reduce hurricane damage may apply to low-grade tornadoes. These include retrofitting the structure with metal brackets to attach the roof rafters to the wall structure and prevent roof lifting in high winds. The garage door, a major weak link in any house, may also be upgraded to a reinforced model designed to resist extreme wind forces.
