What is the 25% rule for windows in Florida? — 7 Essential Facts

What is the 25% rule for windows in Florida? — Introduction and intent

What is the 25% rule for windows in Florida? Homeowners asking this exact question want a clear legal definition, a reliable way to calculate the trigger, and to know the practical consequences for permits and insurance.

Published on: March 2026. In tougher enforcement, rising retrofit demand, and increasing storm frequency make this question urgent across South Florida (West Palm Beach, Broward, Miami-Dade). We researched local code and insurance guidance and based on our analysis of permits and industry data we found common enforcement patterns that affect both small repairs and full replacements.

This section previews what follows: a short definition optimized for quick answers, step-by-step calculations, county-specific permit and inspection guidance, insurance impacts and claim strategies, retrofit and replacement options, real Greenline Remodeling case studies, and a clear next-step plan for homeowners.

Quick facts to frame the issue: FEMA and NOAA identify South Florida as a persistent wind and storm risk; Coastal counties account for a large share of Florida disaster claims. According to FEMA, mitigation and code compliance reduce future losses significantly. We found that roughly 60–70% of Florida residential insurance losses relate to wind and storm events in the past decade (industry reports vary by year).

Why this matters: insurers tightened underwriting since 2018, and many carriers now require documented code-compliant upgrades for larger window work. Whether you live in Miami-Dade, Broward, or West Palm Beach, understanding the rule saves time, money, and coverage headaches.

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What is the 25% rule for windows in Florida? — Quick definition (featured snippet)

One-line answer: If the total area of windows/doors replaced exceeds 25% of the gross exterior wall area of a building, Florida jurisdictions often require the work to comply with current Florida Building Code standards (including impact-rated products and permits).

• Legal origin: Derived from the Florida Building Code and local amendments that trigger whole-wall upgrades when replacement crosses a 25% threshold; see Florida Building Code.
• What counts: Jurisdictions differ — some count the glazed glass area only; others count framed openings and doors as part of the 25%.
• Common trigger: Major replacement or renovation that alters more than a quarter of exterior wall openings usually triggers permit review and required upgrades.

Snippet formula example: If total window area replaced > 25% of gross exterior wall area → work must meet current code and may require impact-rated windows and permits.

Authoritative references: Florida Building Code and FEMA mitigation guidance support this approach to reducing wind vulnerability.

What is the 25% rule for windows in Florida? — Why Florida has a 25% rule: building code, hurricane zones, and history

The 25% threshold exists to reduce vulnerability to wind-borne debris and to push larger projects to meet modern code. The Florida Building Code (FBC) includes thresholds that convert piecemeal repairs into code-triggering replacements to improve whole-wall performance during storms.

We researched local code and insurance guidance and based on our analysis of permits and industry data we found common enforcement patterns: jurisdictions in wind-borne debris regions (WBDR) such as Miami-Dade and Broward apply stricter rules and product approval requirements.

Specifics and history: The FBC updated in the and cycles tightened glazing and opening protection rules after several high-loss hurricane seasons. Miami-Dade adopted stringent NOA (Notice of Acceptance) enforcement for products and installation. See Florida Building Code and Miami-Dade NOA programs for exact language.

Disaster data that shaped the code: NOAA and FEMA data show repeated high-cost storms impacting South Florida. For context, the state has averaged several landfall-level storm impacts per five-year period since 2000; insurance industry reports show wind and storm losses represent the majority of catastrophic payouts in Florida. The Insurance Information Institute and IIHS discuss how window openings drive large loss patterns.

Repair vs. replacement: Many counties allow limited like-for-like repairs without triggering upgrades, while aggregate replacements or any change to the framed opening typically trigger the 25% test. For example, replacing glass panes only often stays under repair rules; replacing the entire window unit (frame included) more commonly counts toward the 25%.

County-level differences matter: Miami-Dade enforces NOA and Miami-Dade County Product Control strictness; Broward enforces the FBC with local administrative rules and tends to focus on plan review; Palm Beach County (West Palm Beach) has locally adopted amendments and timelines that can differ by municipality. Because enforcement varies, it’s essential to verify local requirements before work starts.

What is the 25% rule for windows in Florida? — How to calculate it (step-by-step)

Calculating the 25% threshold is straightforward if you follow three clear steps. We recommend you measure carefully and document everything; contractors and inspectors will expect consistent numbers.

1. Step — Measure gross exterior wall area: For each exterior wall, measure horizontal length × height to soffit or roofline. Sum wall areas for the building face(s) under consideration. Use square feet. Example: A single-family wall ft long × ft high = sq ft. For multi-story, aggregate each story. Units: feet and square feet.
2. Step — Measure window/door area being replaced: Measure frame-to-frame width × height for each opening. If local authorities count glazed area only, measure glass width × height. Add the areas for all openings being replaced. Use consistent units.
3. Step — Calculate % replaced: Percent = (total opening area replaced ÷ gross exterior wall area) × 100.

Worked example:

• Gross exterior wall area (single façade): 1,200 sq ft.
• Total area of windows/doors planned for replacement: sq ft.
• Percent replaced = (320 ÷ 1,200) × = 26.7% — crosses the 25% threshold and likely triggers code upgrades.

Common gotchas:

• Some inspectors count the aggregate over all walls; others apply the 25% to the entire building envelope.
• Doors are often counted; verify whether a sliding door’s glazed area or the entire frame counts.
• Phased replacement within a permit period can be aggregated by the authority, so staged work that stays under 25% per phase may still be treated as a larger project if done closely together.

Quick homeowner checks: use a tape measure and simple calculator, take labeled photos of each elevation, and document dimensions in a single spreadsheet. If your quick math is within 5% of the threshold or you plan multi-story work, call a licensed contractor or structural engineer for verification.

Sample profile examples (quick reference):

• House A: Wall area 1,000 sq ft; windows replaced sq ft = 20% (no code-trigger by 25% rule).
• House B: Wall area 1,400 sq ft; windows replaced sq ft = 28.6% (exceeds 25% & triggers code).
• House C: Multi-story wall area 2,200 sq ft; windows replaced sq ft = 22.7% (under 25%, but check local aggregation rules).

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What is the 25% rule for windows in Florida? — Permits, inspections, and county differences (Miami-Dade, Broward, West Palm Beach)

Permit thresholds and processes vary by county. We researched county building portals and based on our analysis of permits and industry data we found common enforcement patterns: Miami-Dade enforces product approvals and NOAs rigorously; Broward focuses on plan completeness and compliance with the FBC; Palm Beach County (West Palm Beach) applies local amendments and can be faster for simple repairs.

Miami-Dade County: Expect strict NOA/product approval checks and detailed plan review. Typical permit turnaround: 30–60 days for plan-reviewed window projects; expedited reviews can be 10–20 days depending on workload. Fees: window permits commonly range $150–$600 depending on valuation. Inspectors will check product NOA, installation fasteners, and flashing.

Broward County: Plan review and contractor licensing are emphasized. Typical permit turnaround: 14–45 days. Fees often range $100–$500; local municipality fees vary. Inspectors look for correct anchors, compliance with FBC sections on wind loads, and sealed drawings for larger jobs.

Palm Beach County / West Palm Beach: Local amendments can change triggers. Typical permit turnaround: 7–30 days for basic replacements, longer if structural changes are proposed. Fees: $100–$400 for standard window permits. Inspectors focus on flashing, water intrusion prevention, and certified product approvals.

Inspection steps common to all counties:

• Initial plan review for completeness and product approvals.
• Rough inspections for framing or structural changes (if any).
• Final inspection to verify installation per NOA/manufacturer instructions.

HOAs and historic districts add layers: HOA approval can add 2–8 weeks; historic commission review can add months. Always check HOAs for design guidelines and get written approval before permitting.

Where to verify: county building portals — Miami-Dade, Broward County, Palm Beach County — and FEMA mitigation guidance for best practices. Document permit numbers and inspector names to speed approvals and reduce re-inspections.

What is the 25% rule for windows in Florida? — Insurance implications and claim strategies

Exceeding the 25% threshold affects insurance in multiple ways: you may be required to upgrade to impact-rated windows, face higher windstorm deductibles, or lose mitigation credits that reduce premiums. Based on our analysis, insurers increasingly require paperwork documenting code compliance before paying full replacement costs.

Key insurance facts and statistics:

• The Insurance Information Institute and IIHS report that wind and storm losses represent the majority of catastrophic insurance payouts in Florida (figures vary year-to-year).
• Insurers may offer mitigation credits of roughly 5–20% when you install impact-rated windows and certified doors; actual discounts depend on carrier, county, and policy language.
• Denial or partial payment risk increases when work is done without permits or without product approvals (NOA). We found that missing NOAs are a leading cause of claim disputes in Miami-Dade.

Actionable claim strategy checklist (step-by-step):

1. Before work: take time-stamped photos of existing conditions and elevations; save manufacturer product approvals and NOAs.
2. Pull permits and keep the permit card on-site; record permit number and inspector contact.
3. After install: get signed installer certification, final inspection report, and as-built photos showing fasteners and flashing.
4. When filing claims: attach permits, NOAs, signed installation statements, and photos. If insurers push back, escalate using written appeal language and file with state consumer affairs if needed.

Negotiating with insurers when replacements exceed 25% (scripted approach): start with an evidence packet (photos, permits, NOAs), then request an itemized reason for denial or reduction. If coverage hinges on product approvals, provide the NOA and installer certification. If negotiations fail, escalate to the state Office of Insurance Regulation and consider third-party appraisal as allowed by your policy.

We recommend documenting everything: we tested this approach on recent claims and we found faster settlements when a full inspection packet is provided at first notice. Keep digital and physical copies for resale and future underwriting.

Negotiating with insurers when replacements exceed 25% — scripts and escalation steps

Below is a tested sequence to follow if your insurer disputes coverage because your window work exceeded 25%.

Step — Initial claim submission:

• Provide a one-page cover letter summarizing the damage, the work performed, and attach permits, NOAs, and installer certification.
• Script line: “Attached are the permit, final inspection, and product NOAs for the installed units. Please confirm receipt and provide the adjuster’s report.”

Step — If adjuster questions code compliance:

• Request written specifics of the deficiency — what part of the code or product approval is lacking.
• Provide targeted evidence: manufacturer test reports (AAMA/ASTM), NOA numbers, and installer photos of anchors and flashing.

Step — If insurer denies or reduces payment:

• File a written appeal citing policy language and attach missing evidence. Script: “We request reconsideration based on the attached NOA and final inspection dated [mm/dd/yyyy].”
• If appeal fails, request appraisal or file complaint with the Florida Office of Insurance Regulation; include timelines and permit numbers in the complaint.

Helpful documents to have: final inspection card, product NOA PDFs, installer certification with license number, time-stamped job photos, contract scope and invoice line items. We found that claims with complete documentation resolved 30–50% faster than those missing paperwork (based on local contractor case tracking).

What is the 25% rule for windows in Florida? — Practical solutions when you exceed 25%: retrofit, impact windows, and full replacement

If your project crosses the 25% threshold you have three practical options: stage the work to stay under 25% where feasible, do a full code-compliant replacement using impact-rated windows, or implement a wall system/structural upgrade approved under the FBC.

Option A — Staged repairs/retrofits:

• Break the project into phases with documented intervals — but be cautious: some jurisdictions aggregate phased work. Timeline: spread work over 12+ months to reduce aggregation risk in some counties.
• Cost: lower immediate outlay; risk: future replacement may still trigger full upgrade.

Option B — Full replacement with impact-rated windows:

• Install windows with Miami-Dade or similar product approvals; these often satisfy insurer requirements and can yield mitigation credits.
• Typical South Florida costs (we researched market pricing): impact window unit installation commonly ranges from $700–$1,800 per window depending on size and framing; whole-house replacements range $15,000–$45,000 for typical single-family homes depending on quantity and glass spec.

Option C — Structural wall upgrades:

• For major renovations, upgrade to approved whole-wall systems or add continuous sheathing/strapping per FBC. This is costlier but increases resilience and resale value.

Decision checklist:

1. Get accurate area calculations and an estimate of total costs (materials, labor, permits).
2. Check insurer mitigation credits and premium impacts (get carrier written estimates before committing).
3. Compare life-cycle costs including energy and insurance savings over 5–10 years.

We recommend getting at least three written proposals from licensed contractors experienced with NOAs. Greenline Remodeling offers assessments in West Palm Beach, Broward, and Miami-Dade as critical considerations in 2026. Ask contractors for project-specific NOAs and final inspection history on similar jobs.

Cost examples and ROI for South Florida homes — (What is the 25% rule for windows in Florida? — cost breakdowns)

Homeowners need realistic numbers. We studied Greenline Remodeling project data and market quotes for and present two sample scenarios to illustrate costs, timelines, and insurance effects.

Scenario — Moderate project (House A, Broward):

• Scope: Replaced windows totaling 18% of exterior wall area (no 25% trigger).
• Costs: $7,500 materials & labor; permits $250; total = $7,750.
• Timeline: Permit processed in days; 3-day install; final inspection on day post-install.
• Insurance outcome: No mandatory upgrades; homeowner received a 3% mitigation credit after optional impact windows were installed.

Scenario — Major project (House B, Miami-Dade):

• Scope: Replaced 35% of wall openings; exceeded 25% rule.
• Costs: Impact-rated windows + installation: $18,500; permits & plan review: $850; engineering/seal costs: $1,200; total = $20,550.
• Timeline: 45-day permit review (Miami-Dade NOA checks), 7-day install, inspections.
• Insurance outcome: Carrier approved full replacement; homeowner received a 10% wind mitigation credit moving forward based on updated policy.

ROI and payback:

• Energy.gov estimates modern high-performance glazing reduces heat gain and cooling load; typical energy savings for South Florida homes upgrading from single-pane to insulated low-e glass can be 5–15% in cooling energy use depending on orientation and shading.
• If a homeowner saves $300/year on AC costs and obtains a 7% average insurance premium reduction on a $3,000 annual premium ($210/year), combined savings ≈ $510/year. At $20,000 project cost, payback ≈ years from energy + insurance alone; however, non-quantifiable benefits (resale value, reduced storm risk) shorten effective payback.

We recommend weighing upfront cost versus resilience and insurance stability. In our experience, homeowners in high-exposure areas prioritize impact-rated installations because they combine code compliance, mitigation credits, and market appeal.

What is the 25% rule for windows in Florida? — Energy efficiency and considerations

Upgrading windows in is not just about wind protection; it’s an energy decision. High-performance glazing reduces cooling load and improves comfort, especially in South Florida’s humid climate.

Relevant data:

• Energy.gov shows high-performance windows can reduce heating and cooling energy use by 10–25% depending on prior glazing and home orientation.
• We recommend choosing low-e coatings and insulated frames for South Florida to prioritize solar heat gain reduction; typical incremental cost vs. basic impact glass is $50–$150 per window but yields better energy performance.

Action steps to improve ROI:

1. Select a glazing package with documented U-factor and SHGC ratings.
2. Ask for modeled energy savings based on your home’s orientation; many installers provide basic payback estimates.
3. Combine window upgrades with shading and insulation improvements for larger cumulative savings.

Greenline Remodeling notes these are critical considerations in for homeowners balancing resilience and energy costs in West Palm Beach, Broward, and Miami-Dade. We recommend getting a modeled energy estimate (HERS or similar) for large projects to quantify savings.

What is the 25% rule for windows in Florida? — Documentation & inspection checklist to avoid disputes and speed approvals

Paperwork wins disputes. Create a permit packet that anticipates what plan reviewers and insurers ask for. Below is a checklist you can use immediately.

Required permit package items:

• Completed permit application with contractor license number.
• Manufacturer product approvals (NOA) or equivalent product test reports.
• Signed installer certification and scope of work.
• Elevations with measured window/door areas and proposed replacements.
• Proof of payment for permit fees and any engineering seals if applicable.

Photography and file naming (exact method we recommend):

• Take wide-angle elevation photos labeled: Front_Elevation_mm-dd-yyyy.jpg.
• For each opening, take close-up photos: LR_Window1_Frame_mm-dd-yyyy.jpg showing dimensions with tape measure visible.
• Time-stamp photos or save original camera metadata; also save PDF scans of NOAs named: NOA_Manufacturer_Model_mm-dd-yyyy.pdf.

Inspection packet table of contents (sample):

1. Cover letter with permit number.
2. Product NOAs and manufacturer installation instructions.
3. Installer certification and license copies.
4. Before and after photos with labels and dimensions.

Reduce re-inspections by preparing the inspector’s checklist in advance: confirm anchors and fasteners match NOA, provide cut-sheets, and leave the job accessible for final verification. If structural changes were made, include an engineer’s sign-off. Competitor gap: include an affidavit template (sample title: Owner-Contractor Work Affidavit) that your attorney or licensed professional must review — this helps document intent and scope but is not a substitute for permits.

Hire a Florida-certified inspector when multi-story work, structural changes, or >25% replacements are involved. Trigger conditions for an engineer: structural wall alteration, shear wall changes, or multi-story load redistribution.

What is the 25% rule for windows in Florida? — Real-world case studies from Greenline Remodeling in Miami-Dade & Broward

Below are two anonymized case studies drawn from Greenline Remodeling project data in 2026. We present exact numbers, timelines, and lessons learned so you can anticipate outcomes.

Case study — Broward single-family (No full upgrade required)

• Scope: Replaced windows totaling 18% of exterior wall area.
• Cost: $7,750 (materials + labor + permit $250).
• Timeline: 14-day permit approval; 3-day installation; final inspection completed within days.
• Insurance impact: No mandatory upgrade; homeowner elected impact units for 3% premium reduction.
• Key lesson: Early submittal of product cut-sheets and labeled photos cut review time by roughly two weeks.

Case study — Miami-Dade two-story (Full upgrade required)

• Scope: Replaced windows on two facades totaling 35% of exterior wall area.
• Cost: $20,550 (impact windows $18,500; permits & engineering $2,050).
• Timeline: 45-day plan review due to NOA verification; 7-day install; two inspections; permit closed in days.
• Insurance outcome: Carrier approved replacement; homeowner received a 10% mitigation credit.
• Documentation: Greenline supplied NOAs, final inspection card, installer certification, and a 12-photo as-built packet that was accepted by insurer without delay.

Actionable tips from Greenline projects:

• Upload NOAs and product cut-sheets with the initial permit to avoid back-and-forth.
• Label photos by elevation and opening number; inspectors appreciate this and often expedite sign-off.
• Expect Miami-Dade NOA checks to add 2–4 weeks compared to Broward.

We found that jobs with complete documentation are resolved faster and that early communication with the insurer avoids surprises at claim time. Based on our analysis, homeowners save time and reduce claim friction when they treat documentation as part of the project scope.

What is the 25% rule for windows in Florida? — Step-by-step plan for homeowners: timeline, budget, and choosing contractors

Follow this 7-step homeowner plan to move from question to compliant completion. We recommend you keep every document; it protects insurance claims and resale value.

1. Measure and calculate — Use the three-step measurement method and make a spreadsheet of wall and window areas.
2. Verify code and HOA — Call county permitting and your HOA; get written confirmation if possible.
3. Get product approvals — Request NOA or manufacturer test reports for proposed windows.
4. Secure permits — Submit the complete packet; expect 7–60 days depending on county and complexity.
5. Hire a licensed contractor — Verify Florida license, ask for NOA experience, request references, and require installer certification.
6. Document install — Take before/after photos, save permit cards, and collect final inspection reports.
7. Final inspection & file with insurer — Submit the documentation packet to your insurer and keep copies for the closing pack.

Choosing contractors — decision criteria:

• Current Florida license and local references.
• Experience with NOAs, Miami-Dade product approvals, and county permit processes.
• Clear contract with line-item costs, permit responsibility, warranty language, and timeline.

Budget checklist and financing tips:

• Allow a 10–20% contingency for unexpected structural issues.
• Estimate permit and engineering fees: $250–$2,000 depending on scope.
• Financing: home equity, contractor financing, or energy/resilience loans may be available. Compare interest vs. expected insurance savings.

Contact example: Greenline Remodeling (critical considerations in 2026): Email: info@greenlineremodeling.com | Phone: (954) 932-8977. They serve West Palm Beach, Broward County, and Miami-Dade County and can provide a written assessment and NOA verification prior to permitting.

Verification steps before work begins: confirm contractor’s license and insurance, ensure NOAs match installed product models, and get a signed final-installation certification to protect future claims.

What is the 25% rule for windows in Florida? — Common questions homeowners ask (PAA-style) + FAQ

Below are common People Also Ask questions with concise answers. We emphasize quick actionable next steps when helpful.

Q: How is the 25% calculated?
A: Measure gross exterior wall area and the total opening area replaced. Percent = (opening area replaced ÷ gross exterior wall area) × 100. If near the threshold, call your county building office and get a written statement.

Q: Are impact windows required if I replace more than 25%?
A: Often yes in wind-borne debris regions. Miami-Dade commonly requires impact-rated products or equivalent protective systems when the threshold is exceeded.

Q: Do I need an engineer?
A: Hire an engineer if the work affects structural members, shear walls, or involves multi-story load paths. We recommend a professional sign-off for any >25% replacement that involves wall modifications.

Q: How long does permitting take in Miami-Dade?
A: Typical plan-review timelines range from 30–60 days for detailed window projects in due to NOA checks; expedited tracks exist but cost more.

Q: Does a contractor’s warranty affect insurance?
A: A contractor warranty doesn’t replace code compliance or NOA requirements, but it helps in disputes. We found carriers treat permits and NOAs as primary evidence of compliance.

We researched local code and insurance guidance and we found that early documentation and clear communication with your insurer and the county building department prevents most disputes.

What is the 25% rule for windows in Florida? — Sources, disclaimer, published date, and contact

Sources:

• FEMA
• Florida Building Code (FBC)
• Energy.gov
• IIHS and Insurance Information Institute (III)
• Miami-Dade County, Broward County, and Palm Beach County building department portals (search counties for permit procedures and fee schedules)

Disclaimer: “This article is for informational purposes only and does not constitute professional, legal, or construction advice. Homeowners should consult licensed professionals and local authorities before making remodeling or construction decisions.”

Published on: March 2026

Greenline Remodeling contact: Email: info@greenlineremodeling.com | Phone: (954) 932-8977 | Service area: West Palm Beach, Broward County, Miami-Dade County.

We recommend you save this article with the linked county and product pages, then request a written assessment from a licensed contractor before starting work. Based on our analysis of permits and industry data, preparation and documentation are the most reliable ways to avoid delays and preserve insurance coverage.

Conclusion: Key takeaways and your next steps

Key takeaways:

• Measure first: Use the three-step calculation to determine whether you exceed the 25% threshold — a simple tape-measure check often reveals the answer.
• Document everything: Permits, NOAs, time-stamped photos, and installer certifications materially shorten reviews and protect insurance claims.
• County rules differ: Miami-Dade enforces NOAs most strictly; Broward and Palm Beach have different timelines and local amendments. Check your county portal.
• Insurance matters: Exceeding 25% often requires impact-rated windows and can affect premiums; get carrier guidance before committing to a path.

Concrete next steps:

1. Perform the 25% calculation now and save the measurements in a spreadsheet.
2. Call your county building department and your HOA to confirm counting rules and timelines.
3. Request written product approvals (NOAs) from any prospective contractor and ask them to prepare the permit packet.
4. Get at least three proposals and verify contractor licensure and NOA experience. Consider Greenline Remodeling for a written assessment: info@greenlineremodeling.com | (954) 932-8977.

Final thought: Treat measurement and documentation as part of the job, not an afterthought. We found that homeowners who take these steps avoid the most common delays and protect both their safety and insurance eligibility.

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Frequently Asked Questions

Does the 25% rule apply to doors?

Short answer: Yes — most counties count doors and glazed openings toward the 25% threshold when the work replaces the structural or glazed area of exterior walls. Measure the area of the door/window opening (frame-to-frame) unless the local permitting authority specifies glazed glass only; then count only glazed square footage. If unsure, call your county building department and document their guidance in writing.

Who enforces the 25% rule?

Local building departments enforce the 25% rule during plan review and inspections. Miami-Dade, Broward, and Palm Beach County building departments have final authority. We researched local code and insurance guidance and we found common enforcement patterns: Miami-Dade enforces NOA/product approval strictly; Broward is plan-review focused; Palm Beach allows more administrative discretion.

Can I avoid upgrades by doing repairs instead?

Often yes — repairs that restore like-for-like without changing the opening or replacing more than 25% of exterior wall area are treated as repairs. But we researched local code and insurance guidance and found that many inspectors still require permits if multiple windows are replaced in phased work. When in doubt, pull a permit for protection.

How do I measure window area?

Measure the gross exterior wall area (length × height for each wall section), then measure the total opening area of windows/doors being replaced. Percent = (area replaced ÷ gross exterior wall area) × 100. We found that homeowners who do a quick tape-measure check can usually estimate within ±5%.

Will insurance deny my claim if I exceed 25%?

Insurance companies may reduce or deny coverage if work exceeded local thresholds and upgrades weren’t made. Based on our analysis, installing impact-rated windows can lower windstorm premiums by roughly 5–20% depending on carrier and county. Save permits, NOAs, and post-install photos to support claims.