ASI 12SK Butyl Sealant is a one part, butyl-based sealant formulated to perform better than the average butyl by using synthetic fibers for more flexibility, better adhesion and greater versatility.

ASI 12SK provides a long-term seal between all types of masonry, steel, aluminum, glass and other common construction/industrial materials. ASI 12SK Butyl Sealant shows excellent resistance to weathering, bubbling, cracking, and other performance issues usually seen with butyl sealants. ASI 12SK conforms to the requirements of Federal Specification TT-S-01657. It is also paintable when using most industrial and commercial paints.


  • Excellent Flexibility
  • Paintable
  • Resistant To UV Degradation & Weathering
  • Good Adhesion Range
  • Excellent Long-Term Physical Properties
  • Non-Slump, Can Use On Overhead & Vertical Applications
  • Non-Staining To Most Substrates
  • Easy To Dispense And Tool At A Variety Of Temperatures

Physical properties

Physical PropertiesTest MethodResult
ViscosityASI Test Method1,200,000 cp (Spindle 7, 4rpm)
Skin Formation TimeASI Test Method120 minutes (70°F, 50% RH)
DensityASTM D147512.02 lbs./gal
HardnessASTM C66135 (Shore A)
Tensile StrengthASTM D412130 psi
Bubble FormationTT-S-001657Pass
Gun GradeASI Test MethodPass (Non-Slump)
QUV TestingASTM G26Pass (10,000 hrs)
Service TemperatureASI Test Method-20°F to 180°F
Cure In Depth After 7 DaysASI Test Method8mm (70°F, 50% RH)

Strength will start to develop immediately and continue increasing for 7 days after application. ASI recommends testing strength and adhesion on the 7th day. ASI 12SK suggested application temperature range: 5°F to 120°F

Information on this data sheet can change without notice and it is therefore not recommened that these figures be used in spec writing. Ifyou have any questions contact manufacturer’s sales and technical service department.

Conforms / Meets / Exceeds

  • TT-S-01657, Type 1
  • Conforms To USDA Requirements For Non-Food Contact
  • Meets Requirements of AAMA
  • 808.3-05
  • Low VOC (259 grams/liter ASTM D3960)

Common Substrates

  • Glass
  • Steel
  • Cement
  • Painted Metal
  • Many Plastics
  • Aluminum & Galvanized Metal
  • Wood
  • EPDM
  • Porous Surfaces (Concrete, Brick, Etc.)

Common Applications

  • Glass Channel Glazing Panels
  • Curtain Wall Joints
  • Sealing Insulated Glass Units in Metal & Wood
  • General Industrial Applications
  • General Construction Applications
  • Bedding Thresholds
  • Seal Around EPDM
  • Masonry Applications
  • Sheet Metal Work & Sealing
  • Secondary Glazing Seals

Speak with a sales engineer to discuss ASI 12SK or any of our other products or manufacturing services! Use our contact form or call 800-325-7040 now.