Silicone Brush-Grade 422

Silicone Brush-Grade 422 is a ready-to use, high solids, single component moisture cured silicone mastic designed for waterproofing penetrations, curbs, seams, and flashings areas.

  • Superior protection – forms a durable, rubber-like seal
  • Excellent UV protection and reflectivity
  • Superior adhesion to silicone coated surfaces
  • 95% Solids – Uses less material for same dry film thickness
  • Low VOC

5-gallon pail, 2-gallon pail



Silicone Brush-Grade 422 provides elemental protection for architectural surfaces such as vertical walls, masonry, concrete, metal, single ply roof membranes sprayed-in-place polyurethane foam systems and previously coated silicone areas.

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  • Modified Bitumen
  • EPDM
  • Single-ply
  • Smooth BUR
  • Concrete
  • SPF
Surface Prep:

All surfaces to be coated must be clean, dry, and paintable. It may be necessary to power wash and/or prime to enhance adhesion. See application specification for more details.


Only to clean, dry, sound surfaces free of loose articles or other foreign matter. For best results, ambient temperature should be between 50-90°F. Higher temperatures will shorten the cure time and working time for proper application of granules before the material has skinned. Lower temperatures will lengthen the skin over, tack free and ultimate cure time.


Applied coating will cure in 2 to 8 hours depending on temperature and humidity.

Application Coverage (1 gallon) Width Wet Mils Average Dry Mils
Seams 150 linear ft. 4″ 32 30
Flashing Details 50 linear ft. 6″ 64 60

*Coverage rates listed are estimates based on typical conditions.

  • Brush
  • Bulk Gun
  • Roller
  • FM Approved
  • CRRC
  • Miami-Dade County
  • Florida Product Approval
  • UL

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