How to Apply CertaSeal INT Sealant CertaSeal INT™ Sealant CertaSeal INT™ from CertainTeed is a spray-applied, water-based acrylic latex sealant that is quick and easy to install and requires minimal personal protection equipment. Play Close Related Content Residential Roofing Building Insulation Performance Benefits of Sustainable Insulation Fiberglass Insulation Contributes to Green Building. Since the introduction of fiberglass insulation in 1938, it has remained the leading insulation. Learn More Building Insulation Performance Benefits of Sustainable Insulation Building Insulation Increase Energy Efficiency During Heating Season Building Insulation Fiberglass Batt Insulation Contributes to Highest LEED® Certification Building Insulation Safeguarding the Health of Building Occupants Building Insulation Fiberglass Insulation and Vapor Barriers