May 6, 2020
Areas that are prone to high wind events like hurricanes typically have building codes that require skylights and other building features to be impact resistant or protected by impact-resistant devices. The American Architectural Manufacturers Association (AAMA) publishes the standard specifications for these features in the United States. In addition to other requirements, skylights must comply with ASTM E 1996 or AAMA 506, which specify the standard impact resistances for building openings of varying sizes.
Vtech subjects its skylights to more demanding tests, including the following:
Our skylight was the first to pass the extremely rigorous Class 4 Large Hail test, which simulates a particularly severe hail storm. Hailstones typically contain a good deal of air, but this test uses balls of solid ice weighing 64 grams, or about 2 ¼ ounces. Six of these balls were shot directly at a skylight at speeds of 75 mph, including two at the center, two at a corner and two at an edge. The skylight was unaffected.
The Federal Emergency Management Agency (FEMA) has established rigid specifications for the design of safe rooms in both residences and community buildings. FEMA P-361 requires the most durable building materials and best practices in construction, since its purpose is to protect occupants from the most severe storms.
This standard includes three tests for skylights. The first consisted of two strikes from a 15-lb. lumber 2×4 fired at as speed of 100 mph. The first strike hit the center of the glass, and the second hit the corner. The glass broke, although the lumber failed to penetrate the laminate layers of the skylight.
The second test was the design load structural test, which subjected the skylight to positive and negative pressures of 250 pounds per square foot (psf). The third test was the over load structural test, which subjected the skylight to positive and negative pressures of 300 psf. Neither of these tests broke the seal’s integrity.
This concluded the official tests for FEMA P-361, which marked the only time a skylight has met this standard. We then fired the 2×4 four more times at the skylight, which was unaffected.
Vtech Skylights are able to withstand the hard impacts and wind forces from hurricanes without leaking. Our impact tests for Miami-Dade County were submitted under Notice of Acceptance (NOA) 09-0316.03 in 2019. These tests are specified in the Florida Building Code (FBC) and include the following four Testing Application Standards (TASs):
These tests required our skylight to be installed with an air-tight seal over the opening of a pressure chamber. An 8-ft 2×4 was then shot at the skylight with a speed of 50 feet per second (fps), or slightly over 34 mph. This test was performed twice, striking once in the center and once in the corner. It cracked the glass, but failed to penetrate the laminate material.
The pressure chamber was then pressurized to +55 psf, meaning the pressure inside the chamber was pushing against the skylight. The pressure was then reversed to -55 psf so that the air outside the chamber was pushing the skylight inward. This cycle was repeated 4,500 times over several hours to simulate the wind forces produced by a powerful hurricane. Our skylight remained watertight.
We have also performed our own unofficial leak test on a skylight. We wanted to see just how well our skylights, when installed, resist water over an extended period of time. We built a tank, inserted our skylight over the opening, and filled the skylight with water. We then heated the water to 110° for 3 days.
We then dumped in huge buckets of ice on a regular basis to aggravate expansion and contraction, and performed positive pressure tests on the application. After seven years, it still hadn’t leaked, so we called it a success.
And yes, at one point, we even kept a fish in there.
This test simulated the effect of a load from ice and snow on the skylight. We placed an 8,064-lb. weight on the skylight, resulting in a static load of 504 psf. The skylight was unaffected by this test.
These tests show how important the safety of the building’s occupants is at Vtech. Contact us today for more information on our skylight’s resistance to severe weather.