Florida requires a protected opening, not a specific product
Florida's building code doesn't mandate impact windows specifically; it requires exterior openings to be protected against windborne debris, which can be satisfied either by an impact-rated window and door assembly or by separate protective devices such as shutters over standard glass.
How impact windows are tested
Impact-rated windows are tested under ASTM E1996, the standard specification covering exterior windows, curtain walls, doors and impact protective systems for hurricane-prone regions, using large-missile and small-missile impact tests followed by cyclic pressure loading that simulates sustained hurricane wind.[1]
Large-missile-rated products are required for glazing within 30 feet of grade, where wind-borne debris risk is highest, while small-missile-rated products apply higher up.[1]
How shutters fit into the same requirement
A shutter system paired with standard glass can satisfy the same debris-protection requirement as an impact window, provided the shutter product itself carries the matching approval for the wind zone. The tradeoff is action required before a storm: shutters have to be deployed, while an impact window is protected at all times by design.
The High-Velocity Hurricane Zone raises the bar further
Miami-Dade and Broward counties fall inside Florida's High-Velocity Hurricane Zone, created after Hurricane Andrew in 1992 exposed how badly standard products and inconsistent testing had performed.[2]
Inside the HVHZ, large-missile testing uses a 9-pound length of lumber fired at 50 feet per second, followed by cyclic positive and negative pressure testing, and design wind speeds in the zone commonly run from about 170 to 200 miles per hour depending on the specific site.[2]
A product approved for the rest of Florida isn't automatically approved for the HVHZ; it needs either a Florida product approval specifically marked for HVHZ use or a Miami-Dade or Broward County Notice of Acceptance.[2]
What a Notice of Acceptance actually certifies
A Notice of Acceptance, issued by Miami-Dade's Product Control Section, certifies that a specific window or door assembly passed the county's testing for its high-wind and impact requirements, and building inspectors check at installation that the approved assembly, not just the approved brand, was the one actually installed.[3]
Choosing between the two, in practice
Impact windows cost more upfront but need no action before a storm and typically add year-round benefits like noise reduction and UV blocking. Shutters cost less initially but require deployment, storage, and someone available to put them up before landfall. Inside the HVHZ specifically, whichever option you choose, confirm the exact product's approval number rather than a general "hurricane rated" claim on a brochure.
Outside the HVHZ, Florida's statewide rule still applies
The rest of Florida, outside Miami-Dade and Broward, still requires wind-borne debris protection on new and replacement openings in the windborne debris region along the coast, tested under the same ASTM E1996 framework but without the HVHZ's added large-missile threshold and its county-specific approval process.[1]
That's a real distinction worth confirming with a permitting office directly: two homes a short drive apart, one inside the HVHZ and one just outside it, can face meaningfully different testing and approval paperwork for the same style of window.