Karnak 19 Ultra Rubberized Flashing Cement

Karnak 19 Ultra Flashing Cement is a general purpose asbestos-free flashing cement for repairing leaks in shingles, concrete, metal or asphalt roofs, SBS and APP modified bitumen membranes flashings on walls, chimneys, flues, skylight flashings, downspouts and cornices.

Karnak 19 Ultra is excellent for sealing cracks in concrete and brick, as a joint filler for precast roof slabs, for repair, patch and flashing detail on SBS and APP modified membranes, and for general purpose use in maintenance of exposed buildings and structures.

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Karnak 19 Ultra Rubberized Flashing Cement 3 gallon pails Summer
3 gallon pails
Karnak 19 Ultra Rubberized Flashing Cement 3 gallon pails Winter
3 gallon pails
Karnak 19 Ultra Rubberized Flashing Cement 10 oz tubes
10 oz tubes


Karnak 19 Ultra Flashing Cement is the next generation elastomeric flashing cement. Scientifically compounded with a selection of rubber reinforced asphalt, mineral fibers, and refined solvents. 19 Ultra is manufactured to a heavy pliable consistency for ease of application by trowel. 19 Ultra provides a durable elastomeric coating of greater strength, excellent adhesion and high resistance to water and weathering.

19 Ultra is composed of special chemical ingredients which give it a unique water displacement quality (Wet/Dry). 19 Ultra dries to a tough, flexible, waterproof and corrosion proof rubber coating which gives maximum protection and excellent performance over wide ranges of temperature and weather conditions. Pro Fastening Systems stocks 19 Ultra in 2 consistencies: Summer and Winter grade.

  • Rubberized – elastomeric
  • Wet or dry application
  • Improved low-temperature flexibility
  • Will not shrink or crack
  • Smooth, easy to apply rubber-like trowel consistency
  • Excellent adhesion
  • Excellent resistance to flow (sag) at high roof temperatures
  • Ready to apply – no mixing required
  • Sticks under water the first time
  • Can use with fiberglass membrane under water
  • Greater strength
  • ASTM compliant