Why Recoat a Metal Roof

why recoat a metal roof

Recoating your roof offers many advantages over replacing it, including affordability, speed and safety. This article will help you determine whether your metal roof needs a recoating or replacement as well as discuss the benefits of various metal roof repair coatings.

Identify the Roof Issue

If you’re thinking about a new metal roof coating, ask yourself why you want to recoat. Do you just want to fix an aesthetic issue, or is the roof not functioning properly? If there’s an issue, you first need to identify the problem. You’ll want to make sure the entire roof doesn’t need replacing and ensure any necessary repairs happen so the issue doesn’t happen again.

Speak about the issue with a metal roof coating contractor or a flat roof coating contractor. They will then thoroughly inspect your roof to determine what course of action to take, whether it be a recoating, a repair or a replacement.

When a contractor inspects the roof, they will first determine the structural soundness of the metal panels, looking for damaged areas and deficiencies, which will be addressed before the coating is applied. Deficiencies include missing or loose fasteners, previous coatings that have started to chalk or peel, open seams and broken flashing.

Some of these above deficiencies require repairs, whereas others require a replacement. Deteriorated flexible flashing materials and stripped fasteners, for example, must be replaced.

After the necessary repairs and replacements are finished, the contractor will clear off a small section of the roof and perform an adhesion test, which determines whether the chosen coating will bond properly to the metal panels and existing coatings.

Next, the roof must be cleaned and dried, which will allow adhesion to occur. Some roofs must be treated using a rust-inhibitive primer before they are recoated.

After the above steps are taken, your roof is ready to be recoated. You should pick a day that is sufficiently warm, as most metal roof protective coatings cannot be properly applied below a certain temperature.

types of metal roofs

Determine the Type of Finish You Want

Metal roofs are most commonly made from aluminum, zinc, copper and steel, and each material works best with certain types of finishes.

1. Copper

If you don’t apply a finish to your copper roof, a gray-green color known as a patina will form on the copper over time due to oxidation. The formation of a patina is a natural process and protects the copper from the elements, so many copper roof owners prefer this. However, if you would rather keep your copper roof looking like new, you will have to apply a finish.

You can apply a wide variety of finishes to copper roofs, and the best one will depend on the copper’s composition and the chemicals applied to the copper roof after it was installed. Three common sealants for copper roofs are:

  • Nitrocellulose: This is the most popular option due to its affordability, but you must reapply it every year.
  • Acrylic: An acrylic finish is more durable but also pricier.
  • Silicone: Silicone coatings are a bit costlier than nitrocellulose, but they are perhaps the most effective at preventing patinas from forming.

If you decide you would like to let the patina form naturally, just stop coating your roof. Coatings applied to copper roofs are only for aesthetics since they don’t protect your roof against the elements — copper resists the elements all by itself.

If the patina has developed already and you’d like to remove it, you can restore its original color by power washing it or, if the patina is thick, scrubbing it by hand. Once you’ve removed the patina completely, you can then seal the copper to prevent the patina from forming.

2. Aluminum

Aluminum reacts with the oxygen in the air, creating an aluminum oxide layer that effectively protects the inner layers from further corrosion. Despite this protective layer, however, aluminum is still commonly used together with a painted coating, as its natural patina is not considered attractive.

When choosing a paint for your aluminum roof, it must be a product specifically made for aluminum to achieve good results. Other things you should consider include:

  • Type: The paint should be oil-based. Certain acrylic primers and paints can also work with chalky aluminum, but the product must specify that it works on aluminum.
  • Color: Aluminum paint is available in many different colors, and it can be customized. Pick the color that best suits your building. If you want, you can add pigment to your primer so it matches the final paint color.
  • Use: Consider getting a cooling color, which will increase your roof’s reflectivity. If your roof doesn’t have a cool coating, the sun will heat it up, making the interior uncomfortably warm.
  • Mold and mildew resistance: Mold growth can make a roof look unattractive and old. It’s also a strong allergen that you should avoid.

3. Zinc

Zinc is an extremely long-lasting roofing material, sometimes lasting up to a century. It doesn’t require any protective coating because it protects itself by developing a patina when exposed to the oxygen and carbon dioxide in the air. Even if the surface is scratched, the patina will reform and the blemish will disappear.

4. Steel

Steel roofs naturally corrode and therefore require a special coating to prevent this. The two most popular types of steel roofs — galvanized and galvalume — are defined by the protective coating they use. Galvanized steel features a zinc coating, which protects against corrosion, and galvalume has a coating of both zinc and aluminum, which provides even better protection against the elements.

These materials are extremely long-lasting and do not generally require additional coatings.

Advantages of Recoating A Metal Roof

When owners become dissatisfied with the condition of their roof, their first thought may be to replace it completely, but this is often unnecessary, and they can save a considerable amount of money by simply recoating it. Other advantages of recoating over replacing include:

  • Speed: Recoating your roof takes less time than replacing it.
  • Safety: As recoating is a relatively quick and easy procedure, accidents are less likely to occur.
  • Less debris: Recoating produces less dust and debris, which is very important in processing facilities and plants.
  • Less downtime: Since recoating is a faster process, it will cause relatively little disruption to your business.
  • Less exposure to leaks: Recoating does not expose the inside of your building to leaks.
  • Environmental friendliness: By recoating your roof instead of replacing it, you decrease the amount of construction materials that end up in landfills. You also avoid the large amount of energy consumed in removing an old roof, installing a new one, manufacturing and transportation.
  • Opportunity to change color: If you like your roof material but just want to change the color, you don’t have to replace your roof completely — just paint it a different color.

Kautz Can Recoat Metal Roofs

If you want a high-quality, durable roofing material that will protect your business for many years, work with Kautz Construction. Kautz is a metal roofing coating contractor with metal roofing solutions to meet your needs.

We have served the Lancaster area for over 45 years and have become the go-to service for quality metal roofing due to our expertise and the care and attention we give to each and every customer. Contact us by calling 717-290-7077 or filling out our contact form.

Metal Roofing Coating Contractor