HVHZ Retrofit Compliance Guide

Miami-Dade Retrofit Window Requirements

Complete specifications for impact-rated replacement windows in High-Velocity Hurricane Zones. NOA-approved retrofit solutions meeting FBC 2024 requirements.

185
MPH Design Wind Speed
+70/-90
Min PSF Rating (Exposure D)
50 fps
Large Missile Impact
9,000+
Pressure Cycles

Before & After Retrofit Comparison

Drag the slider to compare standard windows vs. impact-rated retrofit replacements

HVHZ Compliant

Impact-Rated Retrofit

  • NOA-Approved Laminated Glass
  • TAS 201/202/203 Certified
  • +70/-90 PSF Design Pressure
  • Up to 45% Insurance Discount
  • 25+ Year Lifespan
Non-Compliant !

Standard Window

  • Single-Pane Annealed Glass
  • No Impact Certification
  • ~25 PSF Max Pressure
  • No Insurance Benefits
  • Hurricane Shutter Required
← Non-Impact Rated Impact-Rated Retrofit →

Retrofit Window Types for HVHZ

NOA-approved replacement options for Miami-Dade hurricane protection

Insert Replacement

Fits within existing frame opening. Minimal interior/exterior disruption. Ideal for frame-in-good-condition retrofits.

+65/-80
PSF Rating
2-4 hrs
Install Time
$450-750
Per Window
Low
Disruption

Full-Frame Replacement

Complete frame removal to rough opening. Maximum glazing area. Required when existing frame is damaged or undersized.

+80/-100
PSF Rating
4-8 hrs
Install Time
$800-1,400
Per Window
Medium
Disruption

Block Frame (Masonry)

Anchors directly to concrete block or masonry. Common in Florida construction. Provides maximum structural connection.

+85/-105
PSF Rating
3-6 hrs
Install Time
$700-1,200
Per Window
Medium
Disruption

Historic Retrofit

Maintains architectural character while achieving HVHZ compliance. Special NOA categories for historic districts.

+60/-75
PSF Rating
6-10 hrs
Install Time
$1,200-2,500
Per Window
Varies
Disruption

HVHZ Retrofit Installation Process

Code-compliant installation steps for Miami-Dade approval

1

Site Assessment

Measure existing openings, verify structural conditions, document NOA requirements for specific application.

Pre-Installation
2

Permit Application

Submit product NOA, engineering calculations, and installation details to Miami-Dade Building Department.

5-15 Business Days
3

Old Window Removal

Careful extraction preserving rough opening integrity. Inspect framing for water damage or termites.

30-60 Min/Window
4

Opening Preparation

Flash rough opening per FBC requirements. Install pan flashing and weather-resistant barrier integration.

20-40 Min/Window
5

Window Installation

Set unit per NOA specifications. Install fasteners at required spacing (typically 6" from corners, 12" O.C.).

45-90 Min/Window
6

Final Inspection

Miami-Dade inspector verifies NOA compliance, fastener pattern, flashing, and sealant application.

Scheduled Inspection

Retrofit Trigger Compliance Matrix

When HVHZ impact-rated windows are required vs. optional

Retrofit Scenario Impact Required Permit Needed Inspection
Single window replacement (same size, with approved shutters) Optional* ✓ ✓
Single window replacement (no existing shutter protection) ✓ ✓ ✓
Multiple windows (>25% of total glazing area) ✓ ✓ ✓
Window size/location change (structural modification) ✓ ✓ ✓
Adding new window opening ✓ ✓ ✓
Roof replacement triggering building envelope upgrade ✓ ✓ ✓
Insurance claim repair (>50% damage) ✓ ✓ ✓
Voluntary upgrade (existing compliant protection) ✗ ✓ ✓

*Like-for-like replacement allowed only with documented approved hurricane shutter coverage meeting HVHZ requirements.

Retrofit ROI Calculator

Estimate your savings from impact-rated window upgrades

$2,350
Annual Total Savings
$1,750
Insurance Discount (35%)
$600
Energy Savings (20%)

Retrofit Window FAQs

Common questions about Miami-Dade HVHZ window replacement

What are the NOA requirements for retrofit windows in Miami-Dade HVHZ?
Retrofit windows in Miami-Dade HVHZ require a valid Notice of Acceptance (NOA) demonstrating compliance with TAS 201, 202, and 203 protocols. Windows must withstand large missile impact (9-lb 2x4 at 50 fps) and cyclic pressure testing per ASTM E1886/E1996. The NOA must cover the specific frame type, glass configuration, and size ranges for your application.
Can I replace windows without upgrading to impact-rated in Miami-Dade?
In Miami-Dade HVHZ, window replacements that exceed 25% of total glazing area or involve structural modifications must meet current FBC 2024 impact requirements. Single window replacements may qualify for like-for-like replacement if protected by approved hurricane shutters. Always verify with Miami-Dade Building Department before assuming exemption applies to your project.
What is the difference between retrofit and new construction windows?
Retrofit windows (also called replacement or insert windows) install within existing frames, minimizing construction disruption. New construction windows require complete frame removal to the rough opening. Both must meet identical HVHZ impact and pressure requirements when installed in Miami-Dade County. Retrofit options include insert (smallest footprint), full-frame (maximum glass area), and block frame (masonry direct-mount).
What wind pressure ratings are required for retrofit windows in Exposure D?
Miami-Dade HVHZ Exposure D locations (coastal within 1,500 ft of water) require retrofit windows rated for minimum +70/-90 PSF design pressure at standard sizes. High-rise applications above 60 feet may require ratings exceeding +80/-100 PSF depending on building height and geometry. Specific requirements vary by opening size—larger windows require proportionally higher ratings.
How much can I save on insurance with impact-rated retrofit windows?
Florida law requires insurers to offer windstorm mitigation discounts. Impact-rated windows qualifying as "opening protection" typically yield 25-45% premium reductions depending on other building features. Combined with secondary water resistance and roof-to-wall connections, total discounts can exceed 50%. Request a wind mitigation inspection after installation to document credits.
Do retrofit windows require engineering sealed drawings?
Standard residential retrofit installations typically rely on the product's NOA and manufacturer installation instructions. Engineering sealed drawings may be required for: oversized openings exceeding NOA tables, high-rise applications with enhanced wind loads, structural frame modifications, or commercial projects. Miami-Dade plan reviewers determine requirements during permit review.