FAQ – South Florida

While rusting is an inherent characteristic of most raw metals, the metal coils and sheets that become metal panels are engineered, coated, and tested to prevent rust formation for as long as possible. If that wasn’t enough, the paint coatings applied on top of the metal are designed to further help prevent rusting and corroding.

 To easily understand why this is, let’s go through each popular metal material individually:

Galvalume® – The core substrate of Galvalume is steel, a rust-prone material, but it is continuously hot-dipped with 55% aluminum, 43.4% zinc, and 1.6% silicone. This coating combines the strength and cost-effectiveness of steel with the rust-resistance of aluminum. Galvalume was created to have self-healing characteristics that regular galvanized roofing does not.

Any steel roof, including Galvalume, can rust quickly if it’s scratched, perforated, or not properly maintained, especially where there are cut edges without proper hems.

Aluminum – One of the biggest selling points of an aluminum roof is the fact that it doesn’t have red rust, and corrosion is generally minimal as it ages. Aluminum actually develops a white rust that blends well with the color of the metal.

Aluminum is often defined as the best material to use in coastal areas with high rainfall and seawater spray conditions because it defends against rusting for longer periods of time.

Copper – Copper does not rust, but develops a protective covering called “patina”, which develops due to oxidation and sun exposure. There’s not an exact science to when patina will show up or what color it becomes; it can range anywhere from a dark bronze to a blueish-green covering. Some copper roofs have lasted hundreds of years and are famous for their unique hue.

The Statue of Liberty in New York is actually made of Copper; it’s famous color is that of the patina that has developed since its construction in the late 1800’s.

There is a common misconception that metal roofs make a lot of noise during storms. This myth originates from the primitive construction of metal structures such as sheds, canopies, and barns.


When metal roofs are installed on buildings today, the panels are secured above multiple protective layers, including asphalt-felt, fiberglass-underlayment, and solid plywood; each layer reducing vibration which causes noise.

Additionally, most homes have an attic or crawl space above their ceilings which further dampens any sound that may be caused by stormy conditions.

Although the amount of layers and material required vary from county to county, it is common that all include at least one layer of underlayment above solid plywood before installing any type of metal roofing system.

It’s a common myth that metal roofs attract lightning more than concrete or asphalt roofs.

Metal is a great conductor of electricity, meaning it transfers it from one location to another. However, a material’s conductivity does not influence attraction. The factors which do influence where lightning will strike are the height and size of buildings and their surroundings.

In fact, unlike shingles or wood, metal is incombustible, which means it cannot ignite or burn; especially when struck by lightning. This means a metal roof offers superior protection from lightning than its alternatives.

Coastal Metal only fabricates the metal roof systems that are installed by roofing contractors. To ensure proper installation, please contract a trusted metal roof installer in your area.

It is common sense that metal holds heat when left in the sun. What is not commonly known is that metal roofing systems are milled and finished to release absorbed heat quickly (Emissivity) and reflect the sun’s rays (Solar Reflective Index; SRI). On the other hand, asphalt, concrete, and tile shingles absorb and retain heat at significantly higher rates, which increase the overall temperature of your home by 20-25%.

You can expect a metal roof to last at least 2 to 3 times longer than a regular roof. In general terms, count on a metal roof lasting 50 years and more when properly installed. Copper, the most durable of metal roofs, have been in place on some buildings for over 300 years! (See photo below of the Belvedere Palace in Vienna)

To put it in context, the average life span of an asphalt roof is 12 to 20 years. That lifespan can be shorter depending on the pitch of your roof and the climate in your area. Made of oil impregnated paper or fiberglass, asphalt begins to deteriorate as soon as you expose it to normal weather. A metal roof, however, will never decompose.

Other roofing materials have varying degrees of weather-related problems that lead to breakdown. Concrete tile roofs can crack and absorb water with their naturally porous surface.

Metal roofing outlasts concrete, asphalt, clay, or tiled shingles by a landslide and retains its great looks and durability year after year.

Metal roofs are one of the best options for roofing when it comes to hurricanes. Though it’s impossible to call any structure “Hurricane-Proof”, a properly installed metal roof system is capable of handling wind speeds up to 200 MPH. In perfect conditions, tests have pushed that limit even higher!

As stated in FEMA.gov, a big issue with tile shingles are their vulnerability to break from airborne debris. When one tile is broken, this can lead to a progressive cascading failure. Additionally, the tiles themselves become debris that can damage your property, vehicles, and surrounding properties.

Metal roofs are one of the most environmentally sustainable options on the market! At the end of their life-cycle, metal roofs are 100% recyclable. Additionally, sheet metal which is commonly used for roofing is made up of at least 25% recycled content; often times up to 56%.

According to the National Association of Homebuilders Research Center, 20 billion pounds of asphalt shingles are dumped into U.S. landfills every year. If you loaded those shingles into tractor trailers, then lined them up end-to-end, they would make a line from New York City to Los Angeles, back to New York City again, then on to Chicago. It’s clear that metal is the green

“Oil canning” is naturally inherent in sheet metal, appearing as waviness in the flat portions of the panel. This is a completely normal effect of metal roofs, and occurs for many reasons, such as: too much or too little tension on the panel fasteners, wide flat-portions on the panel design, and even unleveled roof decks. Often times, it can appear or disappear depending on the time of day, angle of the sun, and position of view (See photo below).

Unfortunately, there is no 100% cure or remedy that will protect against oil canning, especially because it’s just the nature of metal to try to revert back to its original form. The best thing you can do is to stay alert and recognize oil canning before it’s installed so no cost/labor tear up is needed after installation. That being said, if you do notice some mild oil canning, many metal roofs and wall systems will work out some of the stresses as time passes, so it might take several seasons for the metal to settle and adapt. Oil canning is not grounds for rejection.

Light, shadows and angles often cause optical illusions when it comes to colors on metal roofing. We get many concerned calls from customers thinking their roofer installed two different shades of a certain color. This is rarely the case.

Coastal Metal has many colors available, including different shades of red, blue. green and brown. You can view our current color chart here. Custom color matching is also available at request.

Savings can add up to thousands a year! To start, your metal roof should last as long as two consecutive roof installs made with less durable materials such as asphalt, concrete or clay. Additionally, you can expect to save up to 40% in air conditioning costs according to the Metal Roofing Alliance. Finally, due to the superior protection and longevity provided by a metal roof, most homeowners insurance companies will offer a significant deduction to your premium payments.