Commercial High Wind Demonstration

This test was intended to compare and contrast the high-wind performance of full-scale commercial strip mall–type structures; one was built using common construction practices and the other was built using stronger, safer wind-resistant elements. Actual high-wind events modeled after actual thunderstorm and hurricane conditions were simulated using IBHS’ 105-fan array.

Demo Specs

  • The test buildings were set up as diners and inventory was included in the back near the roll-up door.
  • The two 30 ft x 20 ft, one-story masonry specimens were placed side by side on the 55-ft-diameter turntable inside the IBHS Research Center’s large test chamber.
  • Both structures were equipped with FM Approved roofing assemblies, including the roof cover, roof deck, perimeter flashing and insulation.
  • The difference between the two structures is that on the stronger building, these items were installed using FM Global Standards, while this was not the case for the common practice building.
  • The components used to make the resilient building stronger and safer cost less than 5% of the total cost of the entire structure.
  • IBHS consulted with a number of organizations during the design and production of this demonstration, including the American Society of Heating, Refrigerating and Air Conditioning Engineers, the Door and Access Systems Manufacturers Association, FM Approvals and FM Global, the Masonry Association of Florida, the National Concrete Masonry Association, the National Roofing Contractors Association, the Roofing Industry Committee on Weather Issues, and the Single Ply Roofing Industry.

Demo Highlights

In the common construction practice building: once the wind got inside, the inventory was damaged and lost.

In the stronger construction building: once the simulated “tree branch” shattered the front window, it also displaced some of the inventory. This highlights the importance of window and door protection even in strong construction.

The top wind gust during the test was 136 mph or the equivalent of a 97 mph one-minute sustained wind speed. All wind speeds are referenced to standard open country conditions at an elevation of 10 m (33 ft).

At what wind speeds did the following components on the common practice construction building fail?

  • Flashing: 73 mph wind gust, which is the equivalent of a 52 mph one-minute sustained wind speed.
  • Roll-Up Door: 115 mph wind gust.
  • Wall: after the 2 x 4 (which simulated a tree branch) shattered the window, the wall separated from the building during a 110 mph wind gust, which is the equivalent of 79 mph one-minute sustained wind speed.

The Importance of Window Protection

Before the window was broken, the building’s walls survived a 136 mph wind gust, which is the equivalent of a 97 mph one-minute sustained wind speed.

Use the right products and install them correctly to achieve the best results. The way you put a building together makes all of the difference in how it performs in high winds.

The test was a success and went as planned. The results of the test were as expected with the failure of flashing, the roll-up door, the window and the roof cover attachment. It cost less than 5% more to build the stronger building as compared to the construction cost of the common practice building. In many areas, 5% is less than the cost of sales tax.