Stop Rust and Seam Leaks on Your Commercial Metal Roof

Commercial metal roofs are incredibly durable, but they have a major weakness: thermal movement.

As the sun heats the metal, it expands; as it cools, it contracts. Over time, this constant shifting backs out screws, opens up panel seams, and cracks the seals around penetrations. Combined with rust, these gaps create major leak pathways.

A fluid-applied commercial metal roof restoration creates a seamless, rubber-like barrier that fully encapsulates your metal roof. It seals every fastener, locks down every seam, and stops rust in its tracks—all for a fraction of the cost of a full metal roof replacement.

The 4-Step Metal Restoration Process

Restoring a metal roof requires strict attention to detail. Applying a coating directly over rust or loose fasteners will cause premature failure. The system must be built sequentially to ensure a permanent bond.

Step 1.Surface Prep & Rust Treatment:

The roof is high-pressure washed to remove dirt, oxidized chalk, and loose scale. Active rust must be treated with a chemical rust-inhibitive primer to neutralize corrosion and prevent it from bleeding through the final topcoat.

Step 2.Fastener Tightening & Sealing:

Crews inspect the entire roof, tightening or replacing loose or backed-out screws. Every single fastener head is then encapsulated with a thick, heavy-duty building sealant (often called “fastener caps”) to completely block water entry points.

Step 3.Seam & Flash Reinforcement:

Horizontal and vertical overlapping seams, structural joints, and curb flashings are the most common leak areas. These zones are reinforced using a three-ply method: a heavy layer of mastic or coating, a high-strength fabric mesh embedded directly into it, and a sealing topcoat.

Step 4.Fluid-Applied Topcoat Application:

The final monolithic layer of high-solids silicone or acrylic coating is sprayed or rolled across the entire surface. This seals the remaining metal panels, providing a seamless, highly reflective barrier against UV rays and severe weather.

Material Comparison: Acrylic vs. Silicone for Metal Roofs

Because metal roofs have high positive drainage (slopes), they are excellent candidates for both acrylic and silicone chemistries. However, their physical behaviors differ significantly under temperature extremes.

Feature

Acrylic Elastomeric

High-Solids Silicone

Elastomeric Flex Rate

High. Excellent elongation and tensile strength; easily stretches and snaps back as metal panels expand and contract.

Moderate to High. Highly flexible, but relies more on its chemical stability to resist tearing over moving joints.

Adhesion to Metal

Excellent. Bonds incredibly well to properly primed galvanized steel, aluminum, and galvalume substrates.

Good. Requires a dedicated primer on metal surfaces to achieve maximum physical adhesion.

Cost Profile

Very cost-effective. Ideal for well-sloped metal roofs without structural sagging or internal valleys.

Higher initial investment, but superior resistance to environmental pollutants and dirt pickup.

Frequently Asked Questions

Can you restore a metal roof that has severe rust?

It depends on the depth of the rust. Surface rust and scale can be safely wire-brushed, pressure-washed, and treated with a rust-transforming primer before coating. However, if the rust has caused structural pitting or eaten completely through the metal panel (creating structural holes), those specific panels must be cut out and replaced before restoration can begin.

Do metal roof coatings make the building cooler?

Yes, significantly. A bare or dark-colored metal roof can easily reach temperatures of 140°F to 170°F on a hot summer day. By applying a bright white reflective restoration coating, up to 85% of solar heat is bounced away from the building. This can lower the roof surface temperature by up to 50°F, heavily reducing your building’s HVAC load and cooling costs.

How do you handle moving seams?

During Step 3 of our process, all seams are reinforced with a high-performance fabric embedded between layers of flexible mastic. This creates a reinforced “hinge” that allows the metal panels to expand and contract freely during extreme temperature shifts without breaking the water-tight seal.

Protect Your Real Estate Assets

Schedule a technical site survey today.

Metal Roof Restoration