Foster® 65-05 WB Mastic

Brief Description Foster® 65-05 WB Mastic is a high-quality, fibrated, water-based mastic. It is known for its bright white color and extremely smooth, creamy, and thixotropic consistency, facilitating fast and easy application. This mastic forms a tough, fire-resistive, and flexible dry film, providing a smooth, attractive finish suitable for both indoor and outdoor applications. Key Specifications and Properties Color and Consistency: Bright white, extremely smooth, and creamy thixotropic consistency. Application Properties: Excellent for brush, trowel, and spray applications; non-flammable when wet with a mild odor during application. Flexibility and Finish: Forms a tough, fire-resistive, flexible dry film, offering a smooth and attractive finish. Adhesion: Excellent adhesion to most foil facings, suitable for a variety of thermal insulations including polystyrene and rigid polyurethane board stock insulations. Certifications and Standards Underwriters Laboratories Inc.: Classified and followed-up by UL. NFPA Standards: Meets NFPA 90A and 90B 25/50 requirements. Environmental and Health Standards: MAS Certified Green® California Dept. of Public Health Standard Method v1.2 Contributes to LEED v4 EQ Credit: Low Emitting Materials – Paints and Coatings Compliant with Collaborative for High Performance Schools EQ 7.1 Application and Limitations Temperature Range: Apply between 40ºF (4ºC) and 100ºF (38ºC); protect from freezing until dry. Drying Time: Allow at least 24 hours above 60ºF (16ºC) with 50% relative humidity to resist rain washoff. Surface Preparation: Do not thin; apply to clean, dry, oil-free surfaces without stirring. Outdoor Use: Ensure outdoor horizontal surfaces drain completely; a pitch of at least 1/2 inch per foot (4 cm/m) is required. Color Selection: Select white color for use over polystyrene in outdoor installations. Application Techniques Trowel: Use a clean steel trowel for full-thickness application, avoiding excessive troweling. Brush: Suitable for water-based paints; apply with full brush and spread evenly without overworking. Multiple coats might be needed. Spray: Airless spray application possible; consult Airless Spray Recommendations for equipment details. Cleanup and Maintenance Use fresh water to clean brushes and equipment before the product dries. For dried product, use hot soapy water or strong solvents like chlorinated solvent (non-flammable) or xylol (flammable)