Elastomeric coatings for roofs and other applications are a paramount solution for enhancing the durability and longevity of existing systems, effectively sealing leaks, bolstering energy efficiency, and extending the overall lifespan of the underlying surfaces.
Proper application of elastomeric roof coatings is imperative to ensure their performance and longevity. Incorrect or uneven application may result in vulnerabilities in the coating system, potentially leading to costly rework or repairs down the line.
In this article, we delve into the advantages and common applications of elastomeric roof coatings, while also providing comprehensive guidelines on the correct application procedures.
Also Read: Coating: To Spray or Not to Spray – Making the Right Choice
Understanding Elastomeric Roof Coatings
Elastomeric roof coatings, the most commonly composed of silicone or acrylic, are fluid-applied coatings that solidify into resilient, highly elastic membranes upon drying. Their elastic nature facilitates easy application across various roof surfaces and ensures adaptability to diverse weather conditions.
These acrylic and silicone roof coatings can be applied to new roofs for added weatherproofing to older roofs, seal leaks, reinforce surface integrity, and prolong their lifecycle.
Compatible Surfaces for Elastomeric Coatings
Elastomeric roof coatings are compatible with a wide array of roofing materials, including but not limited to:
- Built-up roofing
- Asphaltic based membranes
- Metal, metal panels
- Fiberglass and acrylic panels
- APP or SBS Modified Asphalt membranes
- Aged EPDM, PVC and TPO membranes
- Concrete
- Exterior-grade plywood
- Sprayed polyurethane foam
- Existing, like elastomeric coatings
Also Read: Liquid-Applied Coatings and Sealants for the Built Environment
Advantages of Elastomeric Roof Coatings
Enhanced energy efficiency and UV protection: Elastomeric roof coatings create a “cool roof” effect, reducing energy consumption and costs during the summer months.
Increased waterproofing and weathering protection: These coatings act as a sturdy shield against rain, snow, ice, and other harsh weather conditions. They also reinforce roofs, especially in areas prone to high winds.
Simplified repair and maintenance: Once installed, elastomeric roof coatings are easy to maintain and repair. Problem areas can be promptly addressed by applying additional coating directly to damaged areas.
Extended roof lifespan: A properly applied elastomeric coating can significantly prolong the life expectancy of a roof, lasting for decades.
Improved building aesthetics: Elastomeric roof coatings are available in various colors and finishes, enhancing the appearance of the building while providing functional benefits.
How to Apply Elastomeric Coatings
To ensure the correct application of elastomeric roof coatings, refer to our instructional videos on Liquid Applied Roofing (LAR) provided below:
Step 1: Assemble Necessary Tools and Equipment
Having the appropriate tools and equipment streamlines the application process, making it more efficient and manageable.
In addition to essential personal safety gear like goggles, hard hats, work boots, gloves, and safety harnesses, ensure you gather solid plastic core roller covers, versatile brushes, scissors, mallets, push brooms, a power drill with a mixer, and the required sprayer equipment for the application process.
Step 2: Clean and Pressure Wash the Roof
Preparation serves as a cornerstone for a successful coating application. Before coating, the roof should be clean, dry, and structurally stable.
Remove all debris and dirt from the roof’s surface. For heavily soiled areas, use a broom or brush to loosen the dirt. Employ a power washer with a 30-degree cleaning tip capable of 2,500 to 3,500 p.s.i. Keep the tip approximately 18 inches from the roof surface and apply with a gentle sweeping motion. Utilize a push broom to direct standing water toward the drains.
Allow the surface to air dry completely before proceeding to the subsequent step.
Step 3: Repair and Reinforce the Roof
Before applying the elastomeric roof coating, it’s essential to address any areas of damage on the roof’s surface. Utilize Polyglass PolyBrite polyester fabric and mastic to reinforce these repaired areas, as well as around any roof penetrations, curbs, and rooftop equipment.
Handling Inside Corner Details
Begin by applying a generous coat of Polyglass base coat to the inside corner. Embed reinforcing polyester fabric into the corner, ensuring it is smoothly integrated into the base coat. Apply additional base coat to seal overlapping pieces of fabric, followed by a saturation coat to cover the fabric area completely.
Managing Outside Corner Details
Similarly, apply a generous coat of Polyglass base coat to the outside corner. Embed reinforcing polyester fabric over the corner to ensure proper adhesion, followed by a saturation coat. Connect the details with an additional 12-inch piece of polyester fabric, applied in the same manner to enhance reinforcement.
Addressing Pipe Penetration Details
For pipes, stands, drains, and scuppers penetrating the roof surface, cut polyester fabric for the finger flashing, allowing it to cover and overlap the pipe by at least 3 inches. Cut an opening in the target flashing for the fabric to slide over the drain pipe. Apply a base coat around the penetration area and work outward horizontally and up the pipe. Apply the finger flashing around the pipe, then add base coating to secure it. Fit the target piece over the pipe and apply a saturation coat.
Reinforcement Measures
If roof reinforcement is necessary, use a Polyglass base coat and 40-inch polyester fabric rolls. Apply the base coat using a roller, carefully unrolling the fabric over the base coat to adhere it. Seal it with another layer of base coat, overlapping fabric rolls by at least three inches. Once dry, the roof is ready for a topcoat.
Addressing Metal Seam Flashing Details
Apply two coats of Polyglass PolyBrite 77 premium SEBS cement along both vertical and horizontal metal seams, ensuring a minimum of 2 inches on each side. For complete encapsulation, add dab of cement over the screw heads to enhance protection.
Step 4: Perform a Field Adhesion Test
Proceed to conduct a field adhesion test on the roof to determine the necessity of primer application.
For this evaluation, attach a test piece of polyester reinforcing fabric by applying primer, placing the fabric, and then applying another coat of primer over it, leaving a two-inch free fabric portion. Allow 24 hours for drying, then pull the fabric using the uncoated segment.
If the coating cleanly separates from the substrate, it indicates the likely requirement for primer application. Conversely, if the primer remains on the surface, primer application may not be necessary.
Step 5: Mix and Prepare Roofing Products
Thoroughly mix all Polyglass products, including the elastomeric roof coating, to ensure proper application.
Utilize a 3/4-inch corded electric drill with a power mixer attachment, ensuring thorough mixing from the bottom up.
Store and Stage all products away from direct sunlight and safeguard them against freezing conditions.
Step 6: Configure Spray Equipment and Apply
For coating application, utilize airless spray equipment with a minimum volume capability of 3/4 gallons per minute and a minimum pressure of 3,300 p.s.i.
Apply the coating uniformly at the specified wet film thickness, maintaining a nozzle distance of 12-18 inches from the surface.
Reach out to our team of specialists who are ready to assist you in selecting the finest elastomeric roof coating products for your upcoming project. Contact us today.