Metal Roof Coating (Options, Process & More)

If you’re looking to extend the life of your metal roof, a metal roof coating is one of the most effective and affordable solutions available to homeowners. Designed to protect against weather damage, corrosion, and energy loss, roof coatings offer both immediate and long-term benefits for your home’s exterior.

In this blog, we’ll cover:

• The top types of metal roof coatings and how they work
• The application process and what you can expect
• Key benefits and maintenance tips every homeowner should know

Whether you’re dealing with leaks, rust, or simply looking to protect your investment, metal roof coatings could be the answer.

🤔 What Is a Metal Roof Coating?

Purpose and Benefits

A metal roof coating is a liquid or spray-applied product that forms a protective barrier over an existing metal roof. It helps seal seams, prevent rust, and enhance energy efficiency. Think of it as a shield that adds years to your roof’s lifespan.

Benefits include:

• Prevents leaks and corrosion
• Reduces energy costs by reflecting sunlight
• Extends the life of your metal roofing without a full replacement

When Should You Consider Coating?

Homeowners should consider metal roof coatings if their roof is:

• 10+ years old and showing signs of wear
• Prone to leaks during heavy rains
• In need of an energy-efficiency upgrade

Regular inspections by a roofing contractor can help determine the best time to apply a coating.

📋 Types of Metal Roof Coating Options

Choosing the right coating depends on your climate, roof condition, and budget. Each option has its own strengths.

Acrylic Roof Coatings

• Water-based and environmentally friendly
• Reflects UV rays effectively
• Easy to apply and maintain

Best for mild climates and homeowners seeking a budget-friendly solution. However, it may not hold up well in ponding water.

Silicone Roof Coatings

• Highly water-resistant and flexible
• Ideal for roofs with standing water
• Long-lasting with minimal maintenance

Silicone is more expensive but provides excellent protection in humid or rainy areas.

Polyurethane Coatings

• Strong and impact-resistant
• Great for roofs with high foot traffic
• Available in aromatic (less UV stable) and aliphatic (UV stable) formulas

A good choice for industrial-style homes or those in hail-prone regions.

Asphalt-Based Coatings

• Typically used on low-slope or flat metal roofs
• Provides a thick, durable barrier
• Can be reinforced with fabric for added strength

More traditional, but less energy-efficient compared to modern acrylic or silicone coatings.

🏠 Preparing for the Coating Process

Proper preparation is critical for a successful coating job. Skipping or rushing this step often leads to coating failure.

Roof Inspection

Before any coating is applied, a professional roofing contractor should inspect the metal roof to identify:

• Existing rust or corrosion
• Loose fasteners or seams
• Old coating failures or buildup

This helps determine whether cleaning or repairs are needed before coating begins.

Cleaning the Roof

A pressure wash is typically required to remove dirt, oils, mildew, and old coatings. In some cases, a degreasing cleaner or rust converter may also be used.

Checklist for cleaning:

• Remove debris
• Eliminate mildew or mold
• Scrape off loose paint or coating
• Rinse thoroughly and let dry completely

Making Repairs

Before coating, it’s important to:

• Seal gaps and fasteners with roofing sealant
• Replace damaged panels or flashing
• Tighten or replace loose screws

These repairs ensure a smooth and long-lasting application of the coating.

✅ 5-Step Application Process for Metal Roof Coating

Here’s a breakdown of what a professional application process typically looks like:

1. Surface Preparation

• Power wash the entire roof
• Remove any rust or loose debris
• Let the roof fully dry before moving to the next step

2. Priming (If Needed)

• Apply a rust-inhibitive or bonding primer
• Primers help coatings adhere better, especially on older roofs

3. Seam and Fastener Sealing

• Seal all screws, seams, and flashing
• Use compatible sealant or mesh tape for added durability

4. First Coating Layer

• Apply the base coat with a sprayer or roller
• Maintain even coverage, typically around 1 to 1.5 gallons per 100 square feet

5. Final Topcoat Application

• Apply a second coat after the base layer cures
• The topcoat seals everything and provides long-term UV and water protection

The entire process can take 1–3 days depending on the size and condition of the roof.

❌ Common Mistakes to Avoid

Skipping Surface Prep

Failing to clean and prepare the roof is the fastest way to shorten a coating’s lifespan. Always clean thoroughly and repair problem areas before applying any product.

Using Incompatible Products

Mixing coating types or applying a new coating over a failing one without testing for compatibility can lead to peeling and cracking. Consult with a roofing contractor for product recommendations.

Ignoring Weather Conditions

Application should happen in dry, mild weather. Rain or extreme heat can affect adhesion and cure time, potentially ruining the job.

🛠️ Maintenance Tips for Coated Metal Roofs

Coating your metal roof is not a one-and-done project—it still requires periodic care to maximize its performance.

Schedule Annual Inspections

A yearly visit from a roofing contractor helps catch minor issues like cracking, fading, or seam separation before they become bigger problems.

Keep the Roof Clean

• Remove leaves and debris
• Rinse with a hose or low-pressure washer
• Avoid harsh chemicals that could damage the coating

Watch for Ponding Water

Although silicone coatings resist water better than acrylic, ponding should still be addressed. Adjust drainage to prevent long-term water accumulation.

⭐️ Benefits of Coating Over Replacement

For many homeowners, metal roof coating is a more practical alternative to full roof replacement. Here’s why:

1. Cost-Effective: Coating is a fraction of the cost of tearing off and replacing your roof.
2. Energy Savings: Reflective coatings lower attic temperatures and reduce cooling costs.
3. Faster Installation: Most coating jobs take only a few days.
4. Less Disruption: You won’t have to deal with loud tear-offs or dumpster rentals.
5. Eco-Friendly: Extending your roof’s life keeps materials out of landfills.

If your roof’s structure is still sound, coating is a smart investment that delivers both protection and value.

💪 Trust Boss Exteriors for Long-Lasting Roof Solutions

Metal roof coating can extend your roof’s life, reduce your energy costs, and improve your home’s weather resistance—all without the cost and hassle of a full replacement. But the quality of your results depends on who you hire.

At Boss Exteriors, we bring years of expertise, certified crews, and high-performance coating systems to every job. From inspecting your roof’s condition to applying the right coating product with precision, our process is thorough and built to last.

Ready to protect your metal roof the right way? Contact Boss Exteriors today and let us help you secure a more energy-efficient, longer-lasting roof.