WC-5 Vinyl Acrylic Coating

Water-Based Weather Barrier Breather Mastic

WC-5 is a heavy-bodied, water-based, vinyl acrylic mastic that protects mechanical insulation from liquid water while allowing water vapor to permeate into or out of the insulation system. For this reason, it is commonly referred to as a “breather mastic”. It is applied by brush, trowel, or sometimes sprayed onto a substrate. After drying it becomes a tough, flexible, color retentive coating which is resistant to weather, alkalis, oil, grease, moisture, and mechanical damage.

Its normal recommended dry thickness for full-scale outdoor protection is 1/16” (63mils), but it also provides excellent protection at thinner thicknesses. A minimum dry film thickness of 40 mils is recommended. WC-5 is USDA acceptable for use in meat, poultry, and food processing plants.