Hurricane-Resistant Windows and Doors

Florida's vulnerability to hurricanes requires stringent guidelines for doors and windows.

After Hurricane Andrew ripped through Florida in 1992, it woke up legislators and municipal code enforcement officials to upgrade building codes to take into account a weather event that occurs frequently in the state. These upgrades included requirements for hurricane-resistant windows and doors. Even after the implementation of revised building codes in the late 1990s, four hurricanes that ravaged the state in 2004 generated 1.66 million insurance claims, totaling more than $20 billion in insured losses. The average claim was $20,000 and one in five homes was damaged. The areas with the most stringent code upgrades are generally coastal areas, with the exception of much of the Panhandle.

Hurricane-Resistant Windows

There are two kinds of impact-resistant windows. Both require heavy-duty frames anchored to reinforced headers. The shatter-resistant glass is much like car windshield laminated glass that will shatter under high impact but remains, for the most part, intact. One type of laminated glass is essentially two panes with an inner shatterproof membrane between them. If the outer glass is shattered, the membrane holds the broken pieces in place The second type is slightly more penetrable. It consists basically of shatter-resistant film applied over the glass that holds shards in place.

Resistance Tests

According to the state code, windows must withstand the impact test of a 6-foot-long two-by-four weighing 9 pounds, traveling at 50 feet per second. It must also pass a small missile test in which the window must remain intact when 30 pieces of roof gravel traveling at approximately 80 feet per second or 50 miles per hour hit the window. The windows are graded according to the South Florida Building Code.

Hurricane-Resistant Doors

The concern with doors is that the frames, hinges and pins are strong enough to withstand the impact of high winds and flying objects. Unless sufficiently anchored, the door itself could blow off. The American Red Cross recommends installing additional bolts, costing from $10 to $40 as of 2010. Owners of older buildings might consider replacing the door frames and doors with a heavy-duty door.

Garage Doors

Garage doors, because of their size alone, are like wind-catching sails that are equally, if not more, susceptible to damage. Once breached, any inside door or windows, furniture and personal effects become vulnerable and dangerous. So equal attention should be paid to fortifying garage doors as any other door. Newer garage doors are built to withstand hurricane-force winds, while older garage doors can be reinforced by installing steel horizontal bracing.

Cost

For new home construction, expect to pay significantly more for hurricane-resistant homes. For existing homes, expect to pay twice the cost you would otherwise pay for an normal replacement window. Depending on the extent of reinforcement for doors and garage doors the costs can be considerable, as well. There is good news in this, however. If the hurricane-resistant windows improve energy efficiency, the cost can be defrayed by up to $30,000 in tax credits for replacing all windows and $1,500 per window. Insurance costs drop considerably, as well. Miami-Dade County is a good example. For a $150,000 pre-2001 masonry construction home built in 1990 in Dade County and a replacement value of $150,000, a $500 non-hurricane deductible, a 2 percent hurricane deductible, and no claims in the past three years, insurance runs about $4,000 a year. That is a middle-of-the-pack example of the premiums of 29 companies. A hurricane-resistant home annual premium would be about $950--a savings of about $3,000 a year, according to figures provided by the Florida Office of Insurance Regulation.

References

• Shopandcompare: Statewide Insurance Rate Comparisons by the Florida Office of Insurance Regulation.
• CNN: Hurricane-Proof Your Home
• Popular Mechanics: Lab Will Simulate 155-mph Storm
• Information Handling Services: University of Florida: Florida Building Code Revisions Improve Hurricane Protection
• St. Petersburg Times: New Building Code Brings Cost, Confusion