Foster® Vapor-Safe® Mastic 30-90

• FOSTER® VAPOR-SAFE® MASTIC is a high solids, water-based, fire- resistive, flexible, vapor retarder finish for most types of thermal insulation, including polystyrene foam.
• It may be used over dry concrete and finishing cement.
• VAPOR-SAFE® MASTIC is non-flammable when wet and has a mild, latex “paint-type” odor.
• It is designed for heavy duty/industrial use over insulation on pipes, vessels, ducts and equipment operating below ambient temperatures.
• It may also be used indoors. VAPOR-SAFE® MASTIC has the water resistance and low water vapor permeance normally only found in solvent-based products.
• It can be used in high humidity environments and greatly retards water vapor permeation.
• VAPOR-SAFE® MASTIC is ideal for vapor sealing ASJ, FRK and FSK jackets and board facings at joints, laps and over staple and weld pin punctures.
• It is an excellent duct board closure sealant. Do not exceed 1/8" (3.2 mm) wet film thickness.
• VAPOR-SAFE® MASTIC contains no asbestos, lead, mercury or mercury compounds.
• VAPOR-SAFE® MASTIC meets the requirements of Military Specification MIL-PRF-19565C, Type II using method ASTME96, Procedure A permeance and is QPD listed.
• VAPOR-SAFE® MASTIC 30-90 meets the requirements of:
  • MAS Certified Green®
  • California Dept. of Public Health Standard Method v1.2
  • VOC Emissions and Content requirements to contribute to LEED v4 EQ Credit: Low Emitting Materials – Paints and Coatings
  • Collaborative for High Performance Schools EQ 7.1

Preparation

• Do not thin.
• Apply only to clean, dry, oil-free surfaces.
• Keep container closed when not in use.
• Stirring is usually not necessary.
• Application
• To prevent water vapor and moisture infiltration, proper and complete flashing is required.
• Follow flashing specifications.

Heavy duty/industrial outdoor

1. Apply a tack coat of FOSTER® VAPOR-SAFE® MASTIC (color as selected) at 2 gallons per 100 square feet (0.8 l/m2 ).
2. Embed Foster® MAST-A-FAB® White Membrane into the wet tack coat. Smooth membrane to avoid wrinkles and overlap all seams at least two inches (5 cm). Apply finish coat of VAPOR-SAFE® MASTIC, within 1/2 hour after the tack coat application, at 4 gallons per 100 square feet (1.6 l/m2 ).
3. This application shall provide a minimum dry film thickness of 57 mils (1.4 mm).
4. Over cellular glass insulation, increase the coverage to 7 gallons per 100 square feet (2.9 l/m2 ).

Indoor and light duty outdoor

• Apply as above, except that the finish coat shall be 2 gallons per 100 square feet (0.8 l/m2 ) and the minimum dry film thickness shall be 37 mils (0.9 mm).

Trowel or glove

• Use clean steel trowel.
• Apply each coat in full thickness before initial set. Avoid excessive troweling.

• Use fresh water to clean brushes and equipment before product dries.
• Dry product may be removed with hot soapy water (with ammonia added) or strong solvents such as chlorinated solvent (non-flammable) or xylol (flammable).

• Store and apply between 40°F (4°C) and 100°F (38°C), protect from freezing until dry.
• To resist rain wash-off, allow at least 8-12 hours drying time above 50°F (10°C), with a relative humidity of 50%.
• Higher humidity and/or lower temperature may retard drying.
• Always select VAPOR-SAFE® MASTIC in the white color for use over polystyrene on outdoor installations.
• After outdoor exposure, 30-90 may weather to an off-white color.
• Always test foil and paper facings for acceptable adhesion before using.
• Outdoor horizontal surfaces must always drain completely.
• A pitch of at least 1/2" per foot (4 cm/m) is recommended.