Roof Restoration: Silicone over Asphaltic

Silicone roof coating protects against leaks

Stand up to ponding water with GAF Silicone Roof Coatings

Choose GAF Silicone Protective Coatings for protection against leaks due to ponding water, wide temperature application window, and tenacious adhesion when restoring existing metal, asphaltic, aged single-ply, SPF, and previously coated roofs.

Featured silicone coating solutions for asphaltic roofs

5 steps to restoring asphaltic roofs with GAF Silicone Roof Coatings

1. Qualify the roof
  • Ensure the asphaltic roof is clean, dry, and tight
  • Perform moisture scan/identify all wet areas
  • Conduct adhesion test to ensure proper adhesion of coating

2. Prep the substrate

3. Prime the roof
  • Apply a bleed-blocking primer to encapsulate and negate any asphaltic bleed-through
  • Apply GAF Multi-Purpose Primer at a rate of 0.66 – 1.0 gallons per square for smooth surfaces; 1.0 – 1.3 gallons per square for granulated surfaces

4. Detail seams, flashings, and penetrations
  • Treat all seams using GAF Silicone Mastic
    - Tight seams: apply GAF Silicone Mastic at a rate of 160 linear feet per gallon
    - Loose seams: must be three-coursed with GAF Silicone Mastic and 6” GAF Premium Fabric
    - Three-course loose seams at a rate of 75 linear feet per gallon
  • Treat all curbs, penetrations, and drains with GAF Silicone Mastic and 12” GAF Premium Fabric
    - Three-course at a rate of 160 linear feet per gallon

5. Coat the roof
  • Apply GAF Unisil Silicone and GAF Unisil High Solid Silicone per the specifications for a 10/15/20-year limited warranty or guarantee1
    - GAF silicone can be brushed, rolled, or spray-applied
  • GAF Unisil Silicone will require a minimum of two coats
  • GAF Unisil High Solid Silicone can be applied in one or multiple coats
    - For one-coat systems ensure the roof is 2:12 slope or less
    - Apply at a maximum of 2 gallons per square
  • Consistently check wet mil thickness for uniform coverage

Roof coating options for every type of roof restoration

Additional Resources

Use these links to connect with the products and people you need to get the job done.


Find distributors that carry GAF low-slope products and systems.


Find answers to questions and concerns.

Connect with your GAF Technical Sales Rep

Want hands-on roof coating training? Talk to a local rep, dedicated to supporting your business.

Building a better GAF Commercial around you

At GAF, we are constantly optimizing our product line based on your feedback. So whether it’s TPO, liquid-applied roofing, or anything in between, there’s a GAF roofing system for your needs.

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Property Owners
Whether you manage one property or 1,000, we’re building the products and programs you need to reroof, restore, or maintain your investment.
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