739 BrushSeal™ Coating is an economical but effective vapor-barrier coating for use over all types of thermal insulation on cold systems. It is specifically formulated for optimal use on systems operating below ambient temperature but not below 32º F, but it can be used on colder systems as long as adequate insulation thickness is present. It effectively retards the passage of water vapor on applications such as chilled water lines, air conditioning ducts, or other pipes or vessels within these temperature parameters. Colder systems than the above are better protected with Vimasco’s 749 VaporBlok™ which has a lower perm rating and is designed for heavy-duty applications. On all cold systems, vapor barrier coatings will only perform well when the proper thickness of insulation is used.
739 BrushSeal™ is formulated to have a smooth consistency which is easy to apply by brush. It can also be sprayed with the proper equipment. It is compatible with most normal types of thermal insulation used on commercial and industrial jobs, and normal facings such as ASJ, FSK, etc. If the application is to be directly on a foil facing it should be tested first for proper adhesion of the coating.
739 BrushSeal™ is a safe, water-based product which has a mild latex type odor. It is fire resistive, meeting 25/50 flame and smoke requirements, and maintains its white color after application. It can be used indoors or outdoors though it should be noted that when exposed to UV light its color will dull slightly. Being a water-based product, 739 should not be applied on flat surfaces where it will be subjected to ponded water.
Protect from freezing during shipping and storage. After application, it must be protected from freezing and from precipitation or condensation until it is completely cured.
