Pecora BC-158, made from virgin butyl rubber, is a one-part gun-grade sealing, glazing and caulking compound. Pecora BC-158 provides a long- lasting durable seal of dissimilar and similar surfaces between joints due to the recognised durability of butyl rubber. Questions? Contact us
Provides a long-lasting and durable seal between all types of steel, masonry, aluminum, wood, glass and other common construction materials. Used also as a sealant for glass in flashings in construction of curtain wall, mullions, channel glazing panels, installing insulated glass pieces in wood frames or metal and caulking joints. BC-158 is USDA approved for use in food processing plants.
Joint Design: For optimum perform- ance, joints should be designed for no more than 5% extension or compression. Neither the width or the depth of the joint should be less than 1/4” (6 mm).
Ideally, the depth should be one half the width.The recommended maximum width is 3/4” (19 mm), with a depth range of 1/4” to 3/8” (6 to 9 mm).
Surface preparation: Joints must be dry, clean and free of foreign matter, including curing and form-release agents in protective coatings on aluminum or concrete joints. Priming is not necessary.
Joint Backing: Materials for joint backing control the depth of the sealant and permit the sealant to be installed under pressure. Joints should be filled to within 1/2” of the surface with polyurethane or polyethylene backer rod, preferably of a non-absorbing, non-gassing type. Use a size that will be compressed by approximately 25% when installed. Use a bond breaker tape at the bottom of the joint to prevent three-sided adhesion when it is not possible to use a backer rod and allow the sealant to have free movement after it has cured.