749 Vapor-Blok Water Based Elastomeric
749 Vapor-Blok™ is a premium quality water-based vapor-barrier coating which effectively prevents water vapor from passing through it. It is designed to prevent the passage of water vapor into thermal insulation on cold systems or surfaces colder than ambient temperature. It is compatible with virtually all types of thermal insulation including Foamglas and can also be applied to a variety of other types of substrates as needed. It is a safe, easy to apply water-based latex emulsion, but it achieves the type of low perm rating normally associated with solvent-based products.
749 Vapor-Blok™ has a smooth, creamy consistency most suitable for application by brush (it can also be sprayed with the proper spray equipment). For applications where a heavy build is desired, a heavy-brush/trowel grade is available (method of application should be specified when ordering). It has a pure white color, which remains white in service and matches most white jacketings and facings. It is excellent for protecting the insulation on cold air ducts, chilled water lines, cold storage equipment, and other similar cold systems.
749 Vapor-Blok™ is a very low-odor, low VOC coating when compared to other coatings of this type, and thus it is preferable to workers on the job site and also when being applied in inhabited spaces. It achieves its low perm rating at only 30 mils dry film (30 sq. ft/gal), therefore jobs can be completed using less material than with competitive products.
749 Vapor-Blok™ is very effective vapor-barrier coating and should not be used where a breathing coating is required. It meets the 25/50 flame and smoke requirements of NFPA 90A, and complies with MIL-C19565C, Type II, and is QPL listed.