19 Ultra Rubberized Caulk

Karnak #19 Ultra Flashing Cement is the next generation flashing cement. Scientifically compounded with a selection of rubber reinforced asphalt, mineral fibers, and refined solvents. Karnak #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. Karnak #19 Ultra is composed of special chemical ingredients which give it a unique water displacement quality (Wet/Dry). Karnak #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. Karnak #19 Ultra is available in 3 consistencies: Summer, Semi and Winter.


  • Rubberized - elastomeric
  • Wet or dry application
  • Improved low-temperature flexibility
  • Improved water and weather resistance
  • 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
  • Greater strength
  • VOC compliant
  • ASTM compliant


Consistency: A smooth rubber-like trowel consistency which will readily spread on and adhere to vertical and horizontal surfaces without sagging.

Character of Dried Film: Excellent adhesion to masonry, steel, cured concrete, shingles, asphalt roofing, skylight flashings and a variety of other surfaces.

Film Performance Characteristics: The dried film retains its elasticity and ductility so that the material will resist extreme variations in temperature and weather.

Sag Resistance: Excellent resistance to flow at high roof temperatures on vertical surfaces.

Homogenized: Thoroughly mixed and consistent throughout.


Karnak #19 Ultra Flashing Cement is a general purpose flashing cement for repairing leaks in shingles, concrete, metal or asphalt roofs, flashings on walls, chimneys, flues, skylight flashings, downspouts and cornices. 19 Ultra is excellent for sealing cracks in concrete and brick, as a joint filler for precast roof slabs and for general purpose use in maintenance of exposed buildings and structures.


  • ASTM D-4586 Type I
  • ASTM D-3409
  • Fed Spec SS-C-153 Type 1


All surfaces should be clean, dry and free from oil, grease, dust, dirt, loose paint or other foreign matter. Excess water should be removed, if possible, before application of #19 Ultra.


Spread Karnak #19 Ultra Flashing Cement to an average thickness of 1/8" (approximately 8 gallons per square) and press tightly into joints, seams or cracks.


  • Spread Karnak #19 Ultra Flashing Cement over the damaged area at an average thickness of 1/8".
  • Embed Karnak Cotton, Glass or Polyester Membrane reinforcement in the #19 Ultra Flashing Cement.
  • Apply an additional coat of Karnak #19 Ultra Flashing Cement over the entire patch at an average thickness of 1/8".


Tools and other equipment should be thoroughly cleaned with mineral spirits, taking necessary precautions when handling combustible materials. To clean hands use #709 Karnak Karna-Klean or a waterless hand cleaner.


Combustible Mixture: do not use near open flame. Avoid breathing solvent fumes and prolonged contact with skin. Do not take internally. If swallowed, do not induce vomiting. Call a physical immediately.

Keep out of reach of children. Keep container covered when not in use. Do not thin. Consult MSDS for further safety precautions. Dispose of in an environmentally safe manner.


Available in 3 gallon buckets, 5 gallon pails and 10 oz. calking cartridges.

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Kanopy Reflective Roof Maintenance Solutions
  • Reduce Energy Use
  • Lowers Peak Energy Use, reducing energy costs year-round
  • Helps the environment, reduces "Heat Island Effect"
  • Extend the life of the roof
  • Reduces waste. Helps avoid roof tear-off.
  • Economic compared to roof replacement
  • Eliminates interior building operation disruption