Liquid flashing membrane

  • FastFlash-20oz-sausage
  • FastFlash-application2
  • FastFlash-rough-opening-gypsum-sheathing
  • FastFlash-roller-grade
  • FastFlash-20oz-sausage
  • FastFlash-application2
  • FastFlash-rough-opening-gypsum-sheathing
  • FastFlash-roller-grade


Liquid flashing membrane

FastFlash is a liquid flashing membrane available in gun or rollergrade. Use FastFlash in rough openings, to fill joints and seams, to counter-flash waterproofing and air barrier components in new or existing wall assemblies, and to seal around penetrations. Use FastFlash independently or with compatible R-Guard products to prevent the unwanted movement of water and air through building envelopes.

Available at distributors nationwide. Call 888-216-3036.

Ted Barnekoff - Air & Water Barriers, PROSOCO

Ted Barnekoff, Air & Water Barrier Customer Support

  • Waterproof rough openings on new builds and retrofits
  • Fill in small cracks to seamlessly waterproof transitions and seams
  • Apply FastFlash around almost anything prone to getting wet 
  • SHELF LIFE1 year in tightly sealed, unopened container
  • VOC CONTENT30 g/L maximum
  • FORMViscous paste, mild odor red color
  • PHNot-applicable
  • COVERAGE RATE22-28 sq ft per 29-oz tube, 15-17 sq ft per 20-oz sausage, 50-100 sq ft per gallon.
  • FREEZE POINTNot-applicable
  • FLASH POINT>200° F (>93° C)
  • WT/GAL11.75 – 12.5 lbs
  • AVAILABLE SIZES29-oz tube, 20-oz sausage, 1/2-gal (roller-grade), 2-gal (roller-grade)


FastFlash is a waterproofing, adhesive and detailing compound that combines the best characteristics of silicone and polyurethane. This single-component, silyl-terminated polymer (STP) is easy to gun, spread, and tool, or roller apply to produce a highly durable, seamless, elastomeric flashing membrane. Use FastFlash as a liquid flashing membrane in rough openings, to fill joints and seams, to counterflash waterproofing and air barrier components in new or existing wall assemblies, and to seal around penetrations or protect countersunk fasteners.

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Renaissance Condominiums-FastFlash-case-study

case study

FastFlash earns 10-year performance report

In 2005, FastFlash was used on the Renaissance Condominiums in Seattle, Wash., in a whole-structure building envelope remediation project by Tatley-Grund Building Repair Specialists. In February 2015, that product was verified to be performing as intended by OAC Services, a building enclosure consulting firm.


RELATED: Materials transparency

FastFlash receives Declare label from International Living Future Institute

Declare is regarded as the toughest materials transparency standard in sustainable construction. The process involves disclosing product ingredients down to the 100 ppm range.