roofers on top of commercial roof

Roof Restoration: Silicone over Metal

Protect against metal roof leaks

roofers on top of commercial roof

Stand up to ponding water with GAF Silicone Roof Coatings

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

Featured silicone roof coating solutions for metal roofs

5 steps to restoring metal roofs with GAF Silicone Roof Coatings

1. Qualify the metal roof
  • Ensure the roof is clean, dry, and tight
  • Conduct adhesion test to ensure proper coating adhesion

2. Prep the substrate
  • Make any necessary repairs to the sheet metal and secure or replace all loose or missing fasteners
  • Power wash the roof using GAF Cleaning Concentrate
  • Install sheet metal crickets behind rooftop units, if needed

3. Treat seams and fasteners
  • Treat ridges and rake edges with a roof brush and GAF Premium Fabric embedded into GAF Silicone Mastic
    - Three-course at a rate of 75 linear foot per gallon
  • Seal vertical seams with GAF Silicone Mastic. Typical standing seam profiles do not require seam treatment1
    - Check with GAF Technical Services or the GAF Liquid-Applied Roofing Manual - Seam Treatment Guide
  • Encapsulate all fasteners with GAF Silicone Mastic

4. Detail penetrations
  • Treat all curbs, penetrations, and drains with GAF Silicone Mastic and 12” GAF Premium Fabric
    - Three-course at a rate of 75 linear foot 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.

We’re building new plants for greater capacity, and better systems for faster response and higher visibility.
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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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