Question 1

Will a metal roof lower my insurance premium?

Accepted Answer

Here is the honest answer, which is not the one you will get from most metal roofing advertising: there is no metal-specific credit on the Florida wind mitigation form. Florida’s Uniform Mitigation Verification Inspection Form (OIR-B1-1802) scores your roof covering on whether it has a current Florida or Miami-Dade product approval and on permit dating — not on whether it is metal, shingle or tile. The other scored items (deck attachment, roof-to-wall connection, roof geometry, secondary water barrier, opening protection) are all indifferent to the covering material. What genuinely helps is that a permitted re-roof of any material lets the inspector answer that question favourably, and a re-roof is when deck attachment and a sealed deck get brought up to current standards. Anyone promising you a premium discount for choosing metal specifically is guessing.

Question 2

I live near the water. Is a steel metal roof a bad idea?

Accepted Answer

You need to read the warranty before you sign anything, because this is the single biggest trap in coastal metal roofing. As a concrete example, Metal Sales Manufacturing Corporation’s AZ55 Galvalume warranty explicitly does not apply to sheets exposed to “areas within 1500 feet of salt water, marine atmospheres or salt spray.” If your home is inside that distance, a 45-year perforation warranty may be worth nothing to you. Aluminium substrates are the usual answer near the ocean and at least one Florida manufacturer markets an aluminium line with no coastal setback at all. We will tell you which side of that line your address falls on and get you the actual warranty document, not a brochure summary.

Question 3

What is the minimum roof slope for metal?

Accepted Answer

It depends on the system, and this is where a lot of bad installations start. Under FBC 1507.4.2 there are three separate minimums for metal panels: 3:12 for lapped, non-soldered seam panels without applied lap sealant; 0.5:12 (4%) for the same panels with lap sealant applied per the manufacturer’s instructions; and 0.25:12 (2%) for standing-seam systems. Metal roof shingles are separate again — FBC 1507.5.2 says they “shall not be installed on roof slopes below three units vertical in 12 units horizontal.” If someone proposes an exposed-fastener panel on a low-slope porch or lanai, ask which of those three tiers they are relying on.

Question 4

Can a metal roof go over my existing shingles?

Accepted Answer

Sometimes, and for one specific system the code says so directly. FBC 1511.3 and FBC Existing Building 706.3 carry an exception for “complete and separate roofing systems, such as standing-seam metal roof systems, that are designed to transmit the roof loads directly to the building’s structural system and that do not rely on existing roofs and roof coverings for support” — those do not require removal of the existing covering. That is a real advantage of standing seam. It is not a blanket permission: the same section still requires a full tear-off where the existing roof is water-soaked or already has two or more applications of any covering. We look in the attic and count layers before telling you which applies.

Question 5

How do I know the panels are actually approved for Florida?

Accepted Answer

Check it yourself, in about five minutes. Under Fla. Stat. 553.842(4) roofing products must be approved before use in construction in this state, and under 553.842(5) a product “may not be advertised, sold, offered, provided, distributed, or marketed as hurricane, windstorm, or impact protection” unless it is approved. Ask for the Florida Product Approval number (FL#) or Miami-Dade approval number, then look it up at the Florida Building Commission product approval search. Match the code version, the deck type, the fastener spacing and the allowable pressure against what your contract says. FBC 1507.4 also requires the panels be manufactured under a quality assurance program audited by a third party the Commission has approved for that purpose.

Question 6

What fasteners should be used, and why does it matter?

Accepted Answer

It matters because on an exposed-fastener roof the fasteners are the wear item, not the panel. Every screw carries a sealing washer, and the washer is what is holding water out — there are hundreds of them on a roof, all aging in the same sun. FBC 1507.4.4 is specific about metallurgy: galvanized fasteners for steel roofs, copper or 300-series stainless for copper, aluminium fasteners for aluminium on aluminium supports, and “stainless-steel fasteners are acceptable for all types of metal roofs.” On the coastal side of Volusia County that last sentence is the whole argument. Worth noting too: the Metal Sales warranty quoted above separately excludes panel deterioration caused by contact with fasteners, and puts fastener selection on the building owner.

Question 7

Is metal noisy in the rain?

Accepted Answer

Much less than people expect, because the panels are not spanning open air. On a residential re-roof they go over a solid deck with underlayment beneath them — FBC 1507.4.1 requires metal panels be applied to a solid or closely fitted deck unless the product is specifically designed for spaced supports. The barn-roof drumming sound people remember comes from panels on open purlins with nothing behind them. That is a different assembly from what goes on a house.

Question 8

How long does a metal roof last in Florida?

Accepted Answer

Longer than asphalt, and we are going to decline to give you a specific number, which we would rather explain than fudge. The best available service-life study on standing seam comes from the Metal Construction Association, and it surveyed fourteen sites — every one of them inland, with no marine site included. So its conclusion does not transfer to a house two blocks off the Atlantic, and quoting it at you would be a misuse of it. What that study does support, and what matches what we see, is that fasteners and sealants are the wear items and will likely need attention before the panels do. Distance from salt water is the variable that matters most here.

Question 9

Do you install metal on commercial buildings too?

Accepted Answer

Yes — metal panel systems on low-slope and steep-slope commercial roofs, alongside single-ply and modified bitumen. Commercial work in Volusia County has a different permitting path, including sealed drawings. See our commercial roofing page.

System	How it works	Code minimum slope
Standing seam (concealed clip)	No fasteners through the panel face. Panels are held by hidden clips and the seams are snapped or mechanically seamed, so the weather surface has nothing penetrating it.	Minimum slope 0.25:12 (2%) — the lowest of any metal system, so it works on shallow pitches the others cannot.
Exposed fastener — 5V crimp	Screwed through the panel into the deck, with a sealing washer under every screw head. The traditional Florida farmhouse look, and the least expensive way into a metal roof.	Minimum slope 3:12 without lap sealant, or 0.5:12 (4%) where lap sealant is applied per the manufacturer’s instructions.
Exposed fastener — R-panel / corrugated	Same fastening principle as 5V with a different rib profile. Common on barns, shops, agricultural buildings and light commercial.	Same as 5V: 3:12, or 0.5:12 with lap sealant.
Metal roof shingles / tiles	Pressed metal panels that imitate shake, slate or tile. Used where an HOA or a streetscape will not accept a ribbed panel.	Minimum slope 3:12. The code sets no lower option for metal shingles.

Metal Roofing in Volusia County, FL