Were the Waves Worse Than the Winds?

© 2005 Door & Access Systems
Publish Date: Winter 2005
Author: Tom Wadsworth
Page 60

Were the Waves Worse Than the Winds?
Two Garage Door Engineers Inspect the Damage of Hurricane Katrina

Hurricane Katrina made landfall along the central Gulf Coast of the United States as a Category 4 storm on August 29, 2005. The death and destruction it left behind in Louisiana and Mississippi rivaled any recorded hurricane event in U.S. history.

Yet, in evaluating the damage, what was worse: the winds or the waves? In the Florida hurricanes of 2004-2005, high winds dominated the public’s attention. However, on the Gulf Coast, surging water and flooding from Katrina’s high winds and heavy rains overshadowed the wind damage.

How did our products perform in the face of Katrina’s distinctive assault?

On Sept. 20-21, 2005, Angus Lewis, engineering manager at Ankmar, and DASMA Technical Director Joe Hetzel joined more than 40 expert volunteers investigating post-Katrina wind-related building performance. Their investigations focused on damage to residences throughout southern Louisiana and Mississippi.

For this report, we asked these two engineers about their first-person insights into the performance of garage doors and rolling doors in the Gulf Coast region. Since Hetzel and Lewis participated on different teams, each witnessed different damage conditions in different areas.

Of everything you witnessed, what was the most personally surprising observation?

Lewis: I was surprised that there were so few garage door failures. I was in Pass Christian, La., and eastward. Most of the damage was from storm surge. Outside of the storm surge areas, damage was primarily soffits, fascias, and roofing material.
The Mississippi Gulf Coast is not the same as south Florida. I can only assume that the heavily forested rolling terrain in Mississippi tended to reduce the winds rather quickly, something that couldn’t happen in south Florida.

Hetzel: In my team, I was surprised that some entire structures, including the garage doors, actually survived the storm surge near the coast. Along the coast, I witnessed properties where only foundations remained with no trace of structures.

On the basis of your observations, do you think there is some way garage doors can be built to diminish damage from storm surge?

Hetzel: Perhaps, but breakaway construction could mean that the doors would have a lower wind resistance. Code developers may need to decide if certain locations require protection against storm surge or against high winds.

Lewis: Yes, I don’t think you can have both. But I think builders should consider more breakaway construction in general.

Your best guess: What percentage of the garage doors you witnessed complied with the building code?

Lewis: In my team, I didn’t see any doors that complied.

Hetzel: The failures I witnessed were due to underspecified doors. But I cannot estimate a percentage because code adoption and enforcement is patchwork in Louisiana and Mississippi.

What can door dealers in coastal areas learn from the Hurricane Katrina damage?

Hetzel: Know the local codes, and install doors that meet the code. If no code is being enforced, promote doors that can resist environmental conditions. Also, be aware of the areas that are subject to storm surge or flooding.

Lewis: I agree. I also think that consumers should be educated about the availability of code-compliant doors and the potential for damage when they have a non-code-compliant door.

What can door dealers in non-coastal areas learn from the Hurricane Katrina damage?

Lewis: Hurricane damage can extend a hundred miles or more from the coast. In inland areas that can be subject to the remnants of a hurricane or in any area that is prone to high winds, an effort should be made to up-sell to a more wind-resistant door.

Hetzel: Yes, choose doors that meet your specific conditions, and don’t underspecify.