CRL Gray 1/4" x 1/2" Butyl Glazing Tape - Window Sealant

• Age- and weather-resistant butyl rubber glazing tape
• 100% solids, 0% VOC
• Meets AAMA 804.3, 806.3 & 807.3; ASTM C1281
• Used as exterior primary spacing and glazing seal for windows and curtainwall
• Available in Gray and Black

CRL Butyl Architectural Glazing Tape (SKU: GT407) is an extruded, preformed tape on release paper rolls, formulated from polyisobutylene butyl rubber for long-lasting, flexible weather seals. Designed for exterior glazing applications—including glazing glass into window sashes and sealing metal-to-metal, metal-to-glass, wood-to-glass, and metal-to-plastic joints—this tape accommodates normal expansion/contraction and wind loading. Designed for approximately 10% compression at installation to ensure proper surface contact.


Typical Properties
Base Polymer: Butyl rubber (polyisobutylene)
Solids Content: 100% solids (no asbestos)
Cure Time: Fully cured before application
Hardness: 20 Durometer Shore A @ 77°F (25°C)
Temperature Range: Application 20°F (-7°C) to 120°F (49°C), Service -40°F (-40°C) to 190°F (88°C)
VOC Content: 0%
Joint Movement: ±15% of joint width
Service Life: 20 year minimum

Applicable Standards: AAMA 804.3, 806.3, 807.3; ASTM C1281

Good Glazing Practices
For best results with this exterior glazing sealant tape, ensure surfaces are free of frost and standing water, brushed clean, solvent washed (MEK, toluene, or naphtha) and wiped dry. Apply with positive contact and approximately 10% compression. Keep tapes under compression with clips or wedges during cure. Use 80 Durometer Shore A setting blocks at sill quarter points; use 50 Durometer Shore A spacing shims for lites over 100". Place sill tape above the sight line unless a cap bead is specified—then place tape 3/16" (4.8 mm) below the sight line. Butt ends without stretching; do not overlap. Keep release paper in place until ready to set the glass.

Product Warning / Limitations:
For applications above two floors, use a spacer, shim, or structural cap bead (such as silicone) to prevent over-compression, or specify CRL 100+ Load Bearing Glazing Tape.