Premium Acrylic HydroStop® System
The HydroStop® roof coating system is an affordable solution to extend the life of structurally sound metal roofs.
A fully-reinforced roof coating system assembly that meets FM 4470*
Count on the HydroStop® System for recover, reroof, and new roof applications.
This easy-to-apply roof system offers excellent adhesion to a variety of substrates, including metal, structural concrete, TPO, PVC, Hypalon®, EPDM, polyiso, gypsum roof board, and asphaltic roofs, for a combination of reinforcement and toughness.
*Refer to FM RoofNav for Actual assemblies
Products in the HydroStop® System
GAF Premium Acrylic HydroStop® Top Coat
A professional grade, water-based, acrylic elastomeric coating that is part of the GAF Premium Acrylic HydroStop® Coating System. Get documents
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GAF Premium Acrylic HydroStop® Base Coat
A water-based acrylic base coat. Used in conjunction with the Premium Acrylic HydroStop® Top Coat and the Premium Fabric, it creates the GAF Premium Acrylic HydroStop® System. Get documents
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Learn about warranty and guarantee coverage
Warranty infoHydroStop® System Case Studies
5 simple steps to metal roof restoration
with the HydroStop® System
1. Qualify and prep the roof
- Ensure the roof is clean, dry, and tight
- Conduct adhesion test to ensure proper coating adhesion
- Make any necessary repairs to the sheet metal and secure or replace all loose or missing fasteners
- Power wash roof using GAF Cleaning Concentrate
- Install sheet metal crickets behind rooftop units, if needed
2. Prime rusty areas
- Treat rusty areas with GAF Metal Roof Primer
3. Treat seams and fasteners
- Seal horizontal seams, ridges and rake edges using a roof brush with GAF Premium Brush-Grade Acrylic Flashing and 12” GAF Premium Fabric (Three-course at a rate of 30 linear feet per gallon)
- Vertical seams: Seal with GAF Premium Brush-Grade Acrylic Flashing
- Fasteners: Encapsulate all fasteners using GAF Premium Brush-Grade Flashing
4. Detail penetrations
Apply GAF Acrylic Base Coat to help improve adhesion of the GAF Acrylic Top Coat and mitigate any asphaltic bleed-through- Apply Acrylic Base Coat per the specifications for a 10/15 year warranty, can be brushed, rolled, or spray-applied
5. Coat the roof
- Apply two coats of GAF Premium Acrylic HydroStop® Top Coat per the specifications for a 10/15/20-year limited warranty or guarantee
- GAF acrylic can be brushed, rolled, or spray-applied
- Option for additional surface coating with GAF Kymax™ Coating
Download the complete installation steps
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