How to Tell If Your Windows Are Impact Resistant

Florida's Florida Building Code defines impact-resistant glazing as a laminated assembly tested to ASTM E1886 and E1996. E1886 is the performance test. E1996 is the specification standard. The assembly must survive a 9-pound 2×4 lumber missile at 50 feet per second and 9,000 pressure cycles afterward. Every unit that passes earns either a Florida Product Approval number (FL#) or a Miami-Dade Notice of Acceptance (NOA). The FL# is issued by the Florida Building Commission. The NOA is required for properties in the High-Velocity Hurricane Zone (HVHZ). The HVHZ covers all of Miami-Dade and Broward counties. These numbers are not optional marketing claims. They are mandatory code references. They must appear on the physical product and on the building permit. Without them, the window does not legally qualify as impact-rated under Florida law. This is true no matter how thick or heavy the glass appears. A single missing approval number disqualifies the entire opening from the wind-mitigation insurance discount available under Florida OIR guidelines.

ASTM E1886 and E1996 are the 2 core test standards that define how to tell if windows are impact resistant at the manufacturing level. E1886 covers the actual performance test. That test involves a missile impact followed by pressure cycling. E1996 sets the specification for design, materials, and minimum performance levels based on wind zone. When you see both standards etched into a glass corner, it confirms the unit was manufactured to the full Florida HVHZ (High-Velocity Hurricane Zone) protocol. Some older windows carry only one standard number. That may indicate a lower-rated product approved under an earlier code cycle. For properties in Miami-Dade and Broward counties, both ASTM references are required for full HVHZ compliance. If you are evaluating windows on a home in Coral Gables or Fort Lauderdale, you need to see both E1886 and E1996 in that corner etch. That confirms the highest level of storm protection.

Absent markings are more common than most homeowners expect. This is especially true in homes built or renovated between 1995 and 2005. Contractor documentation practices were inconsistent during that period. If you cannot locate an ASTM etch, FL# label, or permit record, the most reliable next step is a wind-mitigation inspection. That inspection uses the OIR-B1-1802 form. This is the official Florida Office of Insurance Regulation form used by insurance companies to verify storm-protection features. A licensed general contractor or a certified building inspector completes the inspection. They physically document each opening's protection type and sign the OIR-B1-1802 under their license. You can learn more in our wind mitigation inspection guide. You can also review what the OIR-B1-1802 form covers before scheduling. The inspection typically takes 45 to 90 minutes for a standard single-family home. It produces a report you submit directly to your insurance carrier. That report is used to claim the wind-mitigation discount. The discount can reduce hurricane coverage premiums by 20% to 45% in South Florida.

Florida homeowners who verify impact-rated windows and file the OIR-B1-1802 can save hundreds — sometimes thousands — of dollars per year on hurricane coverage. Citizens Insurance is the state-backed carrier of last resort. It applies opening-protection credits that directly reduce the wind portion of your premium. Private carriers follow similar actuarial tables. The Citizens Insurance wind-mitigation discount page details how credits stack with fully rated openings on all four sides of the home. That includes garage doors and entry doors. According to our impact window insurance savings guide, the average South Florida homeowner saves between $800 and $2,400 annually. Those savings apply once the full OIR-B1-1802 is on file. SafeGuard completes more than 1,200 impact-window, impact-door, and roofing projects per year across South Florida. Our team sees firsthand how often homeowners have uncredited impact openings. In most cases, no one filed the paperwork. Verifying what you already have costs almost nothing compared to the premium savings you are leaving on the table.

Once you know how to tell if windows are impact resistant, the answer dictates your next move. If all 4 markings check out, schedule the OIR-B1-1802. Then start collecting the insurance discount. If markings are partial — some windows pass, others fail — you face a strategic upgrade decision. Replacing just the non-rated windows to complete the set is usually more cost-effective than a full-home replacement. Get a licensed contractor's assessment first. If zero windows pass the check, review the Florida Building Code impact window requirements to understand what is now mandatory for your wind zone. Use our impact window cost calculator to budget the project. Homeowners in Boca Raton, Pembroke Pines, and other coastal communities often discover that upgrading qualifies them for financing options. Those options spread the cost over time. That makes the ROI calculation straightforward within the first 3 to 5 years of ownership.