Roofers spray applying silicone base coat to metal roof

Compromised penetrations can often cause unwanted rust and leaking issues, as is the case with this standing seam metal roof. Properly restoring a rusty metal roof plagued by rust and corrosion requires a system with strong rust inhibitors, elemental protection, and moisture resistance.


Serious rust and corrosion issues were revealed upon closer inspection around the penetrations in this standing seam metal roof.

The installing contractor chose the Met-A-Sil System. This silicone-based system is formulated to seal, waterproof, and preserve roof surfaces from the harmful effects of the sun, wind, and rain. The system’s main component, Silicone 410 or High-Solids Silicone 412, provides superior elemental protection for metal roofs. The contractor chose the high-solids option for this particular job. The system’s performance is the same no matter which silicone top coat is chosen. It is strictly the contractor’s preference.


First, the entire roof was pressure-washed to remove all loose dirt and debris. Additionally, the contractor reinforced the deteriorated metal paneling and replaced/tightened all missing/loose fasteners. Then, the roof was primed with Red Oxide Rust Prime 912. This primer is designed for metal roofs with any rust or oxidation.

Urethane Brush-Grade 522 was applied to seams, transitions, penetrations, and fasteners. This product is a thick, flashing-grade mastic specifically formulated to tightly seal and waterproof areas where leaks are most likely to occur. It also enables the system to withstand the natural expansion and contraction (thermal cycling) of the underlying roof structure.

Finally, two coats of High-Solids Silicone 412 were applied to the roof providing excellent UV protection and reflectivity. Like most American WeatherStar roof coatings, High-Solids Silicone 412 comes available in a variety of standard, premium, and custom-color tints. For this particular roof, the building owner specifically requested a light-grey top coat.


After receiving the Met-A-Sil System, the roof now has a highly reflective, watertight finish with at least 15 years of extended life. Restoring a rusty metal roof like this one required a primer application of Red Oxide Rust Prime 912 to protect it from any further rust or corrosion. American WeatherStar issued a 15-year material warranty on the Met-A-Sil System.

Want to know if the Met-A-Sil Roof Restoration System is right for your roof? To learn more, schedule your free roof inspection with an American WeatherStar Approved Contractor today.

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