Metal roofs are great but if left unattended too long they can start to rust and or have the factory coating wear off. Lets start with a roof that is rusting and is bare metal. You first need to remove as much of the surface rust as possible. Power washing and or wire brushing works best. Next you need to apply a high zinc primer to all rusted areas. Be sure the primer you choose can act as a primer for a solvent based coating. Once the zinc primer has dried you can apply our Roof Repair Mastic to any areas that are in need of repair. The mastic is a patch material that can be put over split seams, bolt heads, curbs and other roof flashings. For really bad areas we would embed some roof mesh into the mastic for added strength.
Once the mastic has dried you can apply two coats of the Armor Metal Roof Coating by either roller or spray or a combination of both. Now you have a completely encapsulated metal roof that is protected against rust, water tight and heat reflective.
Now lets talk about metal roofs that have a paint coating or factory coating on them. First thing you need to do is to determine that the coating is still bonded to the metal. If the coating is delaminating from the metal then it must be removed completely. You never want to coat over another coating that is failing. That goes for whether you’re doing your floor, deck or roof. If the coating is still adhered to the metal firmly then clean it, let it dry and then coat with the Bonding Primer. Let the Bonding Primer dry 24 hrs and then apply two coats of the Armor Metal Roof Coating. If there are any rust spots treat them as detailed above.
If you have a bare metal roof you can apply the Armor Metal Roof Coating directly to it.
So to summarize, never coat directly over rust or a paint finish. Zinc prime any rust areas and then coat the entire roof with bonding primer, same goes for painted metal roofs. Roofs with no coatings or rust can be coated directly with two coats. If your seams, bolt heads and flashings need repair. Do the repairs using the Armor Roof Repair Mastic after any zinc and bonding primer application. If you have any questions as to how to properly coat your roof contact us and one of our roof experts will guide you accordingly.