Impact windows, shutters, and what the code actually requires
Impact windows are not required in Florida. impact-rated windows and approved shutters over standard windows both satisfy the code — impact glass is not mandated†. What is required is that openings in the Wind-Borne Debris Region and the High-Velocity Hurricane Zone† are protected — and the choice between the two routes is about cost, convenience and insurance credit rather than legality.
A great deal of impact window marketing implies the law requires them, and quotes insurance savings of up to 45%. The first is not true. The second is true only of the wind portion of your premium, which is itself only part of what you pay — so the number on your actual bill is considerably smaller than the headline.
What the code requires, and where
- Protection applies in the Wind-Borne Debris Region and the High-Velocity Hurricane Zone†, which between them cover a very large share of Florida — but not all of it. Whether your address is inside one is the first question to answer.
- Every exterior opening counts: windows, doors, skylights and garage doors. A garage door is the one people forget, and it is frequently the largest opening in the building.
- The HVHZ — Miami-Dade and Broward† — is the strictest zone in the country, and it exists because those counties took Hurricane Andrew. products installed in the HVHZ must carry a Miami-Dade Notice of Acceptance†, so the product itself must be approved, not just the installation.
Impact glass against shutters
| Impact windows | Shutters | |
|---|---|---|
| Satisfies the code | Yes | Yes |
| Needs action before a storm | No | Yes — someone has to deploy them |
| Insurance credit | Higher | Lower, because protection is not passive |
| Upfront cost | Substantially more | Substantially less |
| Other benefits | Noise, security, UV, resale | Little beyond storm protection |
| If you are away when a storm comes | Already protected | Only if someone deploys them |
That fourth row down is the one that decides it for many people, and it is not primarily financial. Shutters are cheaper and entirely legitimate, but they only work if somebody is present and able to put them up. For a second home, a rental, or an owner who travels or cannot manage the physical work, passive protection is worth more than the credit difference alone suggests.
The honest version of the insurance saving
Wind mitigation credits apply to the wind portion of your premium, not the whole thing. Credits run 30–45% of the wind portion†, and the wind portion is itself 30–50% of the total premium†. Multiply those and the realistic outcome is 20–30% of the total premium† off what you actually pay — meaningful, but not the number on the brochure.
Credits generally require ALL exterior openings to be protected. Replacing most of the windows and leaving the sliding door or the garage door unprotected can leave you with the cost and none of the credit. If you are phasing the work to spread the expense, find out from your insurer where the credit threshold sits before you decide the order.
Whichever route you choose, the saving arrives through one document: the Uniform Mitigation Verification Inspection Form (OIR-B1-1802)†. Without a current inspection recording the protection, the work exists and the discount does not.
Getting the work done properly
- It needs a permit, and therefore a licensed contractor. This is comfortably over the $2,500† threshold and it alters the building envelope.
- Check the product approval — a Florida Product Approval number, or a Miami-Dade Notice of Acceptance in the HVHZ. Ask for it in writing before signing.
- Installation is as important as the product. An approved window fitted badly does not perform, and it will not pass inspection.
- Get the permit closed with a final inspection. That paperwork is what proves the work to a future insurer and a future buyer.
- Then get a new wind mitigation inspection, because the previous one describes a house that no longer exists.
Florida runs the My Safe Florida Home programme, which provides free wind mitigation inspections to qualifying homeowners and has at times offered grants toward this kind of work. Funding and eligibility change between cycles, so check the current position before paying for either the inspection or the work.
Related
Common questions
Are impact windows required in Florida?
No. Openings in the Wind-Borne Debris Region and the High-Velocity Hurricane Zone must be protected, but approved shutters over standard windows satisfy the code just as impact-rated windows do.
How much do impact windows really save on insurance?
Less than the marketing suggests. Credits apply to the wind portion of the premium, which is itself only part of what you pay, so a realistic outcome is around 20–30% off the total rather than the headline figures quoted.
Are shutters as good as impact windows?
For code compliance, yes. The differences are that shutters must be deployed before a storm, earn a lower insurance credit because protection is not passive, and offer none of the noise, security or resale benefits.
What is the HVHZ?
The High-Velocity Hurricane Zone, covering Miami-Dade and Broward counties. It is the strictest wind zone in the United States, and products installed there must carry a Miami-Dade Notice of Acceptance.
Do I get an insurance credit if I only replace some windows?
Usually not. Credits generally require all exterior openings to be protected, so leaving a sliding door or garage door unprotected can mean paying for the work and receiving no discount.
Do I need a permit for impact windows in Florida?
Yes, and therefore a licensed contractor. The work alters the building envelope, and the closed permit plus a fresh wind mitigation inspection is what proves it to your insurer.
Opening protection requirements come from the Florida Building Code and depend on your wind zone, which is address-specific. Insurance credits are applied by each carrier from the mitigation inspection form. Confirm both with your building department and your insurer.