Impact windows have become the “Gold Standard” for homes in Florida that are subject to hurricanes year in and year out. However, hurricanes do not only present a hazard from flying debris, hurricanes are also pressure events. During a hurricane, there is pressure outside in the storm, and a different pressure inside the sealed home.
What you probably DON’T KNOW about “Impact Windows”
The differential pressures exert strong forces on the structure of the house for a sustained period of time. Whereas an actual impact from flying debris to an Impact Window is a short duration one-time event.
Impact windows are laminate between two panes of glass. This structure is placed in a frame that is sealed with stripping to preserve the moisture barrier of the home. The structure allows the impact windows to flex without shattering. However, in a sustained differential pressure event created by a hurricane that flexible glass can negatively affect the frame and stripping so that the moisture barrier is penetrated. The sustained differential pressure can also cause microfractures to the impact glass that may not be immediately noticeable. When the frame and stripping of the impact glass are compromised it creates cracks and seams through which the very next hurricane can force water through.
So, the answer to the question is “YES” and “NO”! Your impact windows may have survived one hurricane without sustaining a direct impact, but the pressure event may have compromised and weakened the framing and stripping for the next hurricane. The real question is whether the moisture barrier of your home is intact. WindyLaw has trained professional engineers who can come out to your home and determine whether your impact windows are compromised and whether the moisture barrier to your home is intact. With the increased occurrence of hurricanes in Florida, it is better to be safe than sorry and rely on the hype surrounding impact glass.