DASMA TDS 191 - Garage Doors, Tornadoes, and Personal Safety

Every year, homeowners across tornado-prone states assume their garage door is "wind rated" and therefore safe during a tornado. DASMA TDS 191 corrects that assumption plainly and tells you what to do instead.

What this data sheet says

DASMA TDS 191 establishes a single clear position: residential garage doors are not designed or tested to withstand direct tornado impacts. Wind load ratings (expressed in psf) come from ANSI/DASMA 108 uniform static pressure testing. A tornado is a different kind of force: rotating, debris-filled, and capable of producing pressures far beyond any residential door specification.

"There is currently no garage door product that has been independently tested and rated to resist tornado-force winds. Homeowners should not remain in or near the garage during a tornado warning."

The TDS also addresses the common idea of opening the garage door to equalize pressure during a tornado. DASMA recommends against this. An open garage door removes structural support from the wall assembly, makes the building more vulnerable to collapse, and puts the person who opened it at risk while they are doing it.

Key safety guidance from TDS 191:

• Leave the garage before a tornado reaches your area. The garage is one of the most dangerous rooms in a house during a tornado because garage walls have large openings and are less braced than interior walls.
• Do not attempt to open or close the garage door as a tornado approaches. Take shelter immediately.
• If no basement is available, go to an interior room on the lowest floor, away from windows and exterior walls.

When it applies

Colorado sits on the eastern edge of Tornado Alley. Denver and the Front Range see tornadoes less frequently than Kansas or Oklahoma, but they do occur. Jefferson County, Arapahoe County, and Douglas County have all experienced tornado touchdowns in recent decades. The Eastern Plains of Colorado see more frequent tornado activity.

TDS 191 is relevant whenever a tornado watch or warning is issued. It is also useful context when a homeowner asks whether upgrading to a higher wind-rated door provides tornado protection. The answer from DASMA is no: wind load ratings address sustained design pressures, not tornado conditions.

What this means for you

A high-wind-rated garage door protects against straight-line wind events, not tornadoes. Upgrading from a 24 psf door to a 36 psf door improves resilience in a severe thunderstorm with high sustained winds. It does not make the garage a safe shelter in a tornado.

Develop a tornado plan before you need one. Identify the safest interior location in your home. Designate it in advance so that no one is making decisions while a storm is approaching.

After a tornado, have the door inspected before operating it. Even if the door looks intact, the track, brackets, and spring tension may have been affected by wind pressure or debris impact. Operating a structurally compromised door can cause sudden failure.

G Brothers provides post-storm door inspections across Denver metro and the Front Range after severe wind events. If your door was in the path of a storm, we can assess it before you rely on it.

Full text and source

Download DASMA TDS 191 from the official TDS index at https://www.dasma.com/technical-data-sheets/.

This entry covers residential sectional garage doors. Commercial overhead doors face similar tornado limitations; consult the door manufacturer and local emergency management for shelter guidance in commercial facilities.