CRL Tremco® 440 Butyl Architectural Tape is a pre-formed butyl sealant in tape form. The 100 percent solids compound of butyl and polyisobutylene contains no solvents or other volatiles that could escape on exposure, causing shrinkage and sealant failure. Tremco® 440 forms a watertight seal to prevent water infiltration, and has superior weather resistance. Highly adhesive, it remains permanently elastic, even at low temperatures, and is adaptable to many different types of glazing systems. Use Tremco® 440 for non-compression glazing of vision lites and spandrel panels in metal and wood frames in low rise building construction. It can also be used for lap sealing between panels such as steel, aluminum and porcelain, as well as a variety of other joints in shear between similar and dissimilar materials.

Typical Properties:
Base Polymer: cross-linked butyl rubber (polyisobutylene); Solids Content: 100% by weight; Cure Time: fully cured before application; Hardness: 65 durometer Shore "00"; Temperature Range: Application 20°F (-7°C) to 120°F (49°); Service -40°F (-40°C) to 158°F (70°C); Weathering: Unaffected by ultra violet through glass. Remains flexible at low temperatures.

Limitations: Not for use in joints subjected to continuous water immersion or temperatures exceeding 158°F (70°C). Not for use with lites of glass over 75" (1.91 m). As the size of the lite approaches this maximum a higher performance glazing system, such as CRL Tremco® Pre-Shimmed Butyl Tape should be considered.

Applicable Standards: AAMA 800-92, 804.3, and 807.3.

Good Glazing Practices: The following "Good Glazing Practices" are recommended when using CRL Glazing Tapes. Surfaces to be adhered should be free of frost or standing water, brushed clean, solvent washed (MEK, Toluene or Naptha) and wiped dry. At installation, positive contact and approximately 10 percent compression is recommended to fully marry surfaces to be joined. Glazing tapes kept under compression with clips or wedges provide the best seals.

Always use setting blocks (80 durometer Shore "A" hardness) placed at the sill quarter points. Spacing shims are recommended to accommodate wind loading when glass lite is over 100" (50 durometer Shore "A" hardness). Tape placement on the sill rabbet is not to be below the sight line unless a cap bead is specified, then tape is placed 3/16" (4.76 mm) below the sight line to allow for the cap bead. Do not overlap tape to join; always butt ends without stretching. To keep tape surface clean, leave release paper in place until ready-to-set the glass.