We have building codes to reflect how serious our South Florida storms can be. In fact, the most sweeping building code reforms in recent memory happened as a result of the devastating aftermath of Hurricane Andrew in 1992.
Building code changes in recent years have reflected advances in roofing, construction, doors and windows. Any home built after 1996 has required the building adheres to strict standards, and home renovations are also held to the more stringent standard.
Have your windows been upgraded to hurricane resistant quality?
Many homeowners mistakenly think that tempered and impact-resistant glass are the same, but the terms are not interchangeable. Tempered glass is heat-treated, and when it breaks it fragments into small pieces. Because the pieces are small, they are basically harmless and unlikely to cause injury. Tempered glass is typically utilized in places where there is a higher risk of human contact, like hot tub enclosures. Impact-resistant glazing is similar to lamination. When impact-resistant windows are broken, the glass adheres to the plastic interlayer. This prevents wind, water, or debris from the storm from entering the home. It is important to note that all glass (other than impact-resistant window glass) needs to be protected during tropical storms and hurricanes – usually with hurricane shutters.
General Building Code Specifications
The Florida Building Code (or FBC) requires windows to either be impact-resistant or protected by a shutter if the structure is located within one mile of the coast where the wind speed is likely to be 100 mph or greater during a major wind event.
Furthermore, for homes in the High-Velocity Hurricane Zone (HVHZ), every exterior opening must be protected against wind borne debris by shutters or impact-resistant windows. Although not all of Florida is required to have impact-resistant windows, it is a common requirement in the Sarasota and Longboat Key region. Although a direct hit from a hurricane is rare in this area, living on the Gulf Coast means the possibility always exists.
- Manufacturer Identification: All glass window panes and frames must confirm that their construction adheres to the Florida Building Code. This is done by clearly identifying their manufacturer with a permanent marking, which may be sand-blasted, ceramically fired, laser-etched or embossed.
- Glazing: There are additional requirements imposed on windows located in “hazardous” locations. This may include glass in swinging doors, fixed or sliding door panels, storm doors and unframed swinging doors. Any glass surfaces within two feet of a closed door’s vertical edge are also determined to be dangerous. These windows must meet special requirements for “safety glazing” which must endure specified impact loads. The force of impact which each type of glass must withstand is determined by their size, type and function.
- Energy Star: When replacing an old window, complying with Energy Star requirements may qualify you for tax credits. You will also benefit from reduced heating and cooling costs. For windows installed in Florida, the Energy Star qualification criteria dictate that windows have a U-factor no greater than .60. The U-factor demonstrates a window’s effectiveness at keeping heat from escaping, with smaller numbers indicating greater efficiency. Windows must also demonstrate a solar heat gain coefficient (SHGC) of 0.27 or less. The SHGC relates to the degree to which the window allows heat to enter your home; a lower value proves greater resistance of heat energy transfer.
If you are looking to upgrade your home to have hurricane rated windows, or if you wish to understand your options for impact-resistant glass products, call Lindahl Construction. We are here to help.