Built for the Coast: How to Choose the Right Metal Roof in Florida’s Climate.

Choosing the Right Metal Roof: A Guide to Standing Seam and 5V Systems

Metal roofing has become one of the fastest-growing choices for both residential and commercial properties in Florida — valued for its strength, energy efficiency, and timeless aesthetic. Yet, not all metal roofs are created equal. The performance and appearance of your roof depend on panel design, material type, finish system, and installation method.

1. Standing Seam Roofing Systems

Standing seam roofs are defined by their raised vertical seams, typically running 12" to 20" apart, which lock together above the water plane for superior weather protection. Within this category, there are two main attachment methods:

A. Clip-System Standing Seam (Mechanical or Snap-Lock)

• Panels are attached to the roof deck using concealed metal clips, allowing the panel to float during expansion and contraction.

• This system is ideal for long panel runs and low-slope commercial roofs, as the hidden clips prevent penetration and allow thermal movement.

• Benefits: Highest wind uplift resistance, clean aesthetics, minimal maintenance, and long lifespan.

• Common use: Premium residential and commercial buildings in hurricane zones.

B. Nail-Strip Standing Seam

• Panels are fastened directly through a pre-punched flange, simplifying installation and reducing cost.

• While visually similar to clip systems, the panels are more restricted in thermal movement, making them better suited for shorter runs or non-coastal applications.

• Benefits: Lower cost, simpler install; however, expansion stresses can lead to oil canning over time if not properly detailed.

2. 5V Crimp Roofing

The classic 5V-Crimp profile is often seen on coastal cottages, barns, and traditional homes across Florida.

• Panels feature five distinctive "V" ribs that give them a timeless, corrugated look.

• They are fastened through the panel with exposed fasteners, making them more budget-friendly but requiring periodic maintenance.

• Benefits: Cost-effective, strong, and easy to install; Drawbacks: exposed screws can back out or rust if not properly maintained.

3. Material Options and Thicknesses

Metal roofing panels are available in Galvalume and Aluminum, each with distinct advantages:

• Galvalume (Steel coated with zinc and aluminum):

  • Durable, cost-effective, and ideal for inland or non-saltwater environments.

  • Not recommended within 1,500 feet of the coast — the salt air can compromise the coating and void manufacturer warranties.

• Aluminum:

  • Fully resistant to salt corrosion, making it the preferred choice for coastal properties.

  • Slightly softer than steel but lighter and naturally corrosion-resistant.

Standard panel thicknesses (gauges):

• 24 GA – Heavy-duty steel for high-wind and commercial applications.

• 26 GA – Economical steel for inland or low-exposure projects.

• 0.032 Aluminum – Standard for most residential coastal applications.

• 0.040 Aluminum – Heavy-duty option for extreme coastal or commercial conditions.

4. Finish Options: Mill, SMP, and Kynar

The finish determines not only the color but also the longevity and resistance to chalking and fading.

• Mill Finish: Bare metal without paint. Economical but prone to oxidation and uneven weathering. Common for agricultural or industrial use.

• SMP (Siliconized Modified Polyester): Economical painted finish offering decent color retention. Better suited for inland projects.

• Kynar 500® / Hylar 5000® (PVDF): Premium finish with superior fade and chalk resistance — typically backed by a 35- to 40-year paint warranty. Recommended for all high-end residential, commercial, and coastal projects.

Note: Manufacturers often reduce or void warranties within 1,500–3,000 feet of saltwater exposure, especially for Galvalume steel or SMP finishes. Always confirm the warranty coverage when specifying materials near the coast.

5. Panel Widths, Uplift Ratings, and Wind Resistance

• Standard panel widths range from 12" to 20".

• Narrow panels (12"–16") provide higher uplift resistance and reduced oil-canning due to increased rib stiffness.

• Wider panels (18"–20") offer a smoother, more modern look but may experience more surface stress under thermal movement or uplift forces.

In hurricane-prone regions like Southwest Florida, uplift testing (per UL 580 or ASTM E1592) is critical. Narrower panels with heavier gauges (24 GA or 0.040 aluminum) typically achieve the best results for code compliance.

6. Managing Movement and Appearance: Striations, Flat Panels, and Oil-Canning

Thermal expansion and contraction cause metal panels to move slightly each day as temperatures fluctuate.To manage this:

• Striations (small ribs pressed into the panel face): help reduce oil-canning by distributing stress evenly.

• Flat panels: offer sleek, modern aesthetics but are more prone to visible waviness.

• Oil-canning: a natural, cosmetic waviness in flat metal panels — not a performance issue, but can be minimized through proper gauge, striation, and clip spacing.

7. Recommended Manufacturers

Two of the most respected suppliers in Florida include:

• Peterson Aluminum (PAC-CLAD) – Nationally recognized brand offering Kynar-coated steel and aluminum systems with extensive color options and industry-leading warranties.

• Premier Metals of Fort Myers – Regional manufacturer specializing in high-wind rated standing seam and 5V panels, custom trim fabrication, and on-site roll forming.

Both companies supply products compatible with Florida Building Code and Miami-Dade testing standards.

8. The Bottom Line

Choosing the right metal roofing system isn’t just about color or style — it’s about selecting the right combination of panel type, material, finish, and installation method for your environment. Whether it’s a high-end coastal home or a commercial retrofit, proper specification ensures decades of performance and lasting curb appeal.