Wind Resistance - What Dealers Should Know

© 2002 Door & Access Systems
Publish Date: Winter 2002
Author: Tom Wadsworth
Page 52

Technical Tips
Wind Resistance - What Dealers Should Know

By Joe Hetzel, DASMA Technical Director

What should a dealer know in order to determine the wind resistance requirement for a garage door or rolling door product?

Wind resistance requirements are commonly enforced in U.S. high-wind regions, particularly in the hurricane-prone southeastern Atlantic and Gulf Coast regions. However, wind load requirements in newer building codes may be increasingly enforced because of insurance concerns and a region's susceptibility to high-wind events.

If you know how to determine wind loads, you can:

· Improve communication with building officials and design professionals.

· Select the right product for an application and thus reduce or eliminate the possibility of costly follow-up door alteration or replacement.

· Educate the consumer on why a particular door is needed.

Dealers have several areas of concern, but here are three important questions to ask your building department.

· "What is the local design wind speed?" The wind speed value, determined by a contour map, is usually established locally and is in miles per hour. Some municipalities will round up to the nearest 10 MPH; others will interpolate the wind contour map to come up with the nearest MPH.

· · "Is windborne-debris resistance required?" This question should be asked in hurricane-prone regions, such as the Atlantic and Gulf coastlines. Flying debris primarily affects glazed openings in a hurricane event. In Miami-Dade and Broward Counties (Fla.), windborne debris resistance is required for both glazed and non-glazed exterior doors.

· "Is the building enclosed or partially enclosed?" A structure is usually considered partially enclosed if it has a disproportionate amount of glazing on one wall of a structure. However, a structure in a hurricane-prone area may also be regarded as partially enclosed if the openings are not protected against windborne debris.

For further guidance on these issues, contact your door supplier, a local design professional, or DASMA.