How to Apply Roof Coating: Everything You Need to Know

If your roof is weathered and damaged from years of exposure to the elements, you have the ability to renew it using silicone roof coatings. In many cases you can avoid having to re-roof your structure by applying a UV-resistant, weathertight roof coating that can extend the life and improve the functionality of your roof. From barns to sheds to RVs to commercial and residential properties, nearly any structure can benefit from using a quality roof coating.

Roof coatings are made of silicone, acrylic, or urethane and are designed to reflect heat off of the roof's surface while also acting as a barrier for wear and tear that might eventually cause leaks or other damage. Highly reflective white silicone coatings are among the most popular, thanks to their weather resistance, cooling properties, and extended durability.

Roof coatings can be applied to many different roofing materials and on roofs with a variety of different pitches and slopes. Almost all types of roofs can be coated, including flat roofs, metal, modified bitumen, BUR systems, and more.

Roof coatings come in a variety of materials, each with unique benefits and suited for specific roofs. Choosing the right type is important to ensure durability, weather resistance, and long-term protection.

Silicone roof coatings are highly durable and waterproof, making them ideal for flat or low-slope roofs. They resist ponding water, harsh UV rays, and extreme weather conditions. Silicone coatings are perfect for structures exposed to heavy rain or sun, and they require minimal maintenance.

Acrylic coatings are lightweight, cost-effective, and easy to apply. They work best on sloped roofs with good drainage. Acrylic coatings provide excellent reflectivity, reducing heat absorption and lowering energy costs. However, they are not ideal for areas prone to ponding water, as extended exposure can break them down.

Urethane (or polyurethane) coatings are extremely durable and abrasion-resistant, making them a great choice for roofs that experience heavy foot traffic. They adhere well to various surfaces, including metal and modified bitumen. Urethane coatings come in aromatic and aliphatic options, with aliphatic being the more UV-resistant and long-lasting choice.

Asphalt-based coatings are designed for traditional roofing systems, such as built-up roofing (BUR) and modified bitumen. Asphalt-based coatings are ideal for colder climates and offer strong waterproofing. While they are less reflective than other coatings, they excel in extending the life of older roofs.

There are many benefits to applying a protective roof coating, including:

• increasing energy efficiency and reducing costs
• keeping the roof and structure cooler
• reducing damage from weather and other elements
• promoting an environmentally friendly structure

A common question (and hotly debated) is whether you can apply a roof coating to asphalt shingles. The appeal is in the amount of cost savings in applying a silicone coating versus re-roofing the home. Homeowners should talk to their local contractor or roofing specialist to learn more about the severity of roof wear and their options in repairing it. If you decide to use a roof coating as a sealant over asphalt shingles, ensure you get a coating specifically formulated for that substrate.

The first step in applying a roof coating is surface preparation. Clean the roof using a pressure washer or a hose and push broom. The goal is to remove as much debris as possible to give yourself a smooth surface to apply the roof coating. Once you've cleaned the roof, let it dry.

As long as there are no severe cracks or tears in the roof, you can begin to apply the primer or roof coating once it has dried out from washing. Check the roof coating manufacturer's instructions to see if a primer is required. Using a long paint roller or brush, begin to spread the coating onto the roof. Work in 6' to 8' areas, without trying to do the entire roof at once. Spread the coating evenly with a thick coating.

Once the entire roof is covered, it's as simple as letting it dry and cure. Curing time will vary based on the product and environmental conditions, but the product manufacturer should have information on how long it should take to cure. If color is desired, you can add a top coat once it has fully dried out. With the right coating, you can save money, reduce your environmental impact, and add years to the life of your roof!

To get the most out of your roof coating, follow these best practices to ensure proper application and maximum life:

1. Choose the Right Weather: Apply roof coatings when the weather is dry and mild, ideally between 50°F and 85°F. Avoid applying coatings during high humidity or rainy conditions, as moisture can interfere with adhesion.

2. Apply in Sections: Work in small, manageable sections (around 6 to 8 feet at a time). This ensures even coverage and prevents the coating from drying too quickly before you spread it properly.

3. Focus on Edges and Seams First: Use a paintbrush to coat seams, cracks, and edges first, as these areas are more prone to leaks. Then, use a roller for the main roof surface.

4. Apply Multiple Thin Coats: Instead of applying one thick layer, use two thin coats. Allow the first coat to fully cure before applying the second. This provides better coverage and reduces the chance of peeling or cracking over time.

Applying a roof coating is a cost-effective way to extend the life of your roof while improving energy efficiency and weather resistance. Taking the time to prepare the surface and follow proper application techniques will make a significant difference in the results. Remember to invest in the right tools, inspect the roof for damage, and apply multiple thin coats for optimal coverage. 

If you’re unsure about tackling the project yourself, hiring a professional ensures both safety and long-lasting performance. With the right coating and care, you can protect your roof for years to come while saving money and reducing environmental impact. Visit our online store or come on down to the store for more sealants and coatings and for connections to local roofing experts in your area!