Metal Roof Replacement in South Florida

This page is for homeowners replacing an old metal roof, or switching from shingle or tile to metal, anywhere in South or Central Florida. The one thing that matters most: a metal roof resists wind only as well as it matches its product approval, down to the clips and screws. In Miami-Dade and Broward the code goes further and approves the panel, underlayment and accessories as one complete system.¹

When a metal roof needs replacing

Common reasons: rust that has eaten through panels, many loose or failed fasteners on a 5V roof, panels bent or torn by wind, or leaks at seams and flashing that keep coming back. Before you replace, two rules apply:

• The 25 percent rule. No more than 25 percent of a roof, or of a roof section, may be repaired or replaced in 12 months unless the whole roof or section is brought up to code.² If your roof was built or replaced under the 2007 Florida Building Code or later (in effect March 1, 2009), only the part being worked on must meet today’s code.³⁴
• Insurance. Citizens asks metal roofs older than 50 years to document at least 5 years of remaining useful life, or show a full replacement.⁵

If the problem is local, see metal roof repair.

Standing seam or 5V

Standing seam panels are fastened underneath the panel, so the fasteners are hidden and protected from the weather.⁶ 5V crimp panels are screwed through the face. A Florida roofer notes that those exposed fasteners degrade and loosen over time, and says a 5V roof needs new, larger fasteners every 5 to 10 years.⁶

Lifespan estimates disagree, so here is each source:

• Standing seam: 40 to 70 years (PITCH Roofing, Florida).⁶
• 5V: 30 to 50 years (PITCH Roofing) versus 40 to 60 years (Mid Florida Metal Roofing Supply, Central Florida).⁶⁷
• Metal in high-humidity climates: 30 to 50 years for corrugated, longer for standing seam (HomeGuide).⁸

Choosing the metal near salt water

HomeGuide notes that aluminum is often recommended for coastal areas because it resists corrosion, that galvalume resists corrosion better than galvanized steel, and that weathering (Corten) steel is not suitable for tropical or coastal regions.⁸ Most residential metal roofing is 24- or 26-gauge; thicker metal (a lower gauge number) costs more.⁸

The code sets the floor. Outside the HVHZ, galvanized steel panels need a G-90 zinc coating, aluminum-zinc steel (galvalume) an AZ50 coating, and aluminum panels a minimum 0.024-inch thickness.¹ There, when the manufacturer does not specify fasteners, the code requires galvanized fasteners for steel roofs, allows stainless steel on any metal roof, and allows aluminum fasteners for aluminum roofs on aluminum supports.¹

How a metal re-roof works

1. Permit. Florida law requires a permit from the local building department.⁹ We pull it and schedule the inspections.
2. Tear-off. Outside Miami-Dade and Broward, the code requires removal down to the deck when the roof has two or more layers, is water-soaked or deteriorated, or is clay or concrete tile. In Miami-Dade and Broward, nothing may be recovered over tile, slate, wood or metal shingles, or over a deck not fastened to code.¹
3. Deck attachment. On a wood-decked house permitted before the Florida Building Code (March 1, 2002), the deck must be renailed to FBC Existing Building Section 706.7.1 once the old roof is off.²⁴
4. Upgraded underlayment. The same three underlayment options that apply to shingles apply to metal: full self-adhered ASTM D1970 membrane; taped deck joints plus underlayment; or two lapped layers of approved underlayment.¹⁰
5. Roof-to-wall connections, when required. A pre-code home in the wind-borne debris region with an insured value of $300,000 or more must also get stronger roof-to-wall connections, capped at 15 percent of the re-roof cost.²³
6. Panels, fasteners and flashing installed as the product approval details.
7. Inspections and final before the permit closes.

In Miami-Dade and Broward (HVHZ)

The code defines the High-Velocity Hurricane Zone as Miami-Dade and Broward only.¹¹ Here:

• A complete approved system. Metal panels need a product approval for the complete system: panel, underlayment and all related accessories. The whole application method is detailed in the approval and in RAS 133, as applicable.¹ That approval can be a Miami-Dade NOA, searchable on Miami-Dade’s Product Control Search,¹² or a Florida approval listed for HVHZ use, searchable at floridabuilding.org.¹³
• Tested three ways. Metal roofing must pass TAS 125 and TAS 110, plus TAS 100 for wind-driven rain.¹
• Minimum metal. Steel panels must be at least 26-gauge with G-90 corrosion protection; aluminum at least 0.025 inch thick. Assemblies must take foot traffic without damage.¹
• Labels you can check. Metal panels and clips must be labeled on the underside with the product approval number (or the code’s approval wording) and the manufacturer’s mark.¹
• Edges and flashing. Panels may not extend more than 1 inch past the eave, and every intersection is flashed in metal per RAS 111,¹ which sets minimums such as 26-gauge G-90 steel or 0.025-inch aluminum for accessories.¹⁴
• Slope. Metal panels need at least a 2:12 slope; standing seam that passes the ASTM E2140 water-leakage test may go down to 1:12.¹
• Paperwork and inspections. The permit includes the HVHZ Uniform Roofing Permit Application and the Owner’s Notification for Roofing Considerations. Miami-Dade County’s inspection 059 (Tin Cap / Dry In) checks the underlayment before panels go on; 001 is the final.¹⁵¹⁶
• Wind speed. 175 mph for houses in Miami-Dade, 170 mph in Broward.¹⁷

Palm Beach, Southwest and Central Florida

HVHZ rules and NOAs do not apply. Instead:

• Florida Product Approval under F.S. 553.842, searchable by FL number.¹⁸¹³ Metal panels must be made under a quality assurance program audited by a third party approved by the Florida Building Commission.¹
• Slope limits by panel type. Lapped panels without sealant need at least 3:12; lapped panels with applied sealant, 1/2:12; standing seam, 1/4:12.¹⁰
• Your wind speed comes from FBC Figure 1609.3(1) or the ASCE 7 Hazard Tool for your address.¹⁷¹⁹
• Watch the marketing. Florida law bars advertising a product as hurricane or windstorm protection unless it is approved under the state’s product approval law.¹⁸

What it costs

HomeAdvisor puts a Florida metal roof at $6,300 to $28,000 for a 2,000-square-foot roof.²⁰ Panel type drives most of that spread. A Florida roofer quotes standing seam at $15 to $35 per square foot and 5V at $7 to $12;⁶ HomeGuide’s national standing seam range is $9 to $16.⁸ A Central Florida supplier puts an installed 5V roof of about 1,500 square feet at $9,000 to $15,000.⁷ In unincorporated Miami-Dade, the permit for metal and other non-tile roofs is $0.11 per square foot ($0.100 under the county’s pilot for existing homes), with a $147 minimum, plus surcharges.²¹ Our own price comes after we measure. See the metal roof cost guide.

Insurance

• Roof age. Insurers may not refuse or nonrenew solely because a roof is under 15 years old; for older roofs, an inspection showing 5 or more years of life left protects you from a refusal based on age alone.²²
• Wind mitigation. The wind mitigation form records the roof covering and its approval, deck attachment and secondary water resistance.²³ Insurers must offer discounts for wind-resistant features such as roof covering and roof strength,²⁴ but only have to accept the form from signers on the F.S. 627.711(2) list, which does not include roofing contractors.²⁵ Keep your product approval and permit papers for that inspector.
• Contracts. Every roof contract must say the contractor cannot offer rebates or waive your deductible, and must tell you in bold to call your insurer first if the work is tied to a claim.²⁶

Our installation carries a 10-year workmanship warranty; manufacturer warranty terms vary by product. To have your roof measured, contact us. Comparing materials? See shingle roof replacement or tile roof replacement.