IBHS Researchers Put Commercial Construction to the Test

TAMPA, Fla. — The Insurance Institute for Business & Home Safety has conducted the first-ever, controlled high-speed wind test comparing and contrasting the performance of common practice and stronger, full-size commercial buildings in a laboratory.

Two 30 ft. by 20 ft., one-story masonry buildings, similar to those in strip mall shopping centers, were placed side-by-side on the 55 ft. turntable inside the 21,000 sq. ft. test chamber at the IBHS Research Center in South Carolina. One of the test buildings was constructed using techniques common across the U.S., while the other was built using stronger high-wind resistant practices.

The materials used to build both structures were identical, but installation and assembly methods were different. For less than 5 percent of the total cost of construction, the stronger building was improved in critical areas by addition of wind-resistant construction features, including:

• Properly reinforced masonry walls;
• Correctly installed flashing and wind-resistant roof cover;
• Well-anchored roof-top equipment; and,
• Use of roll-up doors with wind locks.

The test included two high-wind demonstrations: part one was modeled on an actual severe thunderstorm that blew through central Texas; part two was modeled on a segment of 2008's Hurricane Ike. The test buildings were subjected to high-speed, multi-directional, gusty winds which reached 136 mph. IBHS researchers observed the following performance failures on the common construction building:

• Roof flashing failed during a 73 mph wind gust (equivalent to a 52 mph one-minute sustained wind speed);
• The overhead, roll-up door failed during a 115 mph wind gust; and
• The side wall collapsed during a 110 mph wind gust (equivalent to a 79 mph one-minute sustained wind speed) after both buildings were pressurized by having a simulated tree branch (a 2”x4” piece of wood) fired through its front window; it is important to note that the walls survived a 136 mph wind gust (equivalent to a 97 mph one-minute sustained wind speed) before the buildings were pressurized — a stark reminder about the importance of effective window coverings or impact resistant windows in high-wind prone areas.

The stronger building did not experience any significant performance failures during this test.

“This test clearly demonstrates that for less than 5 percent of the total cost of construction — which is less than the sales tax was on the building materials themselves — we can build stronger, safer commercial buildings that can better withstand the kinds of high winds experienced during severe thunderstorms and hurricanes,” said Julie Rochman, IBHS president and CEO.

“The stronger building sustained extremely minor damage, while the damage to the common construction building was devastating. That small business would be out of commission for weeks or maybe even months during the cleanup, repair and rebuilding process,” explained Rochman.

She added that “small businesses are vital to the American economy and form the backbone of many communities where residents depend on them to provide basic supplies and services. Unfortunately, one in four businesses forced to close due to a natural catastrophe never reopen, That is why it is critical for businesses to buy, lease or build stronger, safer structures and have a business continuity plan in place.”