Pure Aluminum Solid Foil Radiant Barrier Insulation Ideal for Saunas, Grow Rooms and Crawlspaces. Double-sided 100% PURE Reinforced ALUMINUM Radiant Barrier that blocks 99.9% of the radiant heat transfer. Industrialized and Commercial grade strength with heavy duty woven mylar scrim for tear resistance. Cannot be torn or ripped by hand Passes required ASTM Class 1 Class A fire codes (E84 using E2599 mounting method) for reflective building materials. Waterproof, Weatherproof, Tear proof and wont Oxidize The operating temperature up to 235 degrees Fahrenheit. Easy to install/handle/cut flexible MADE IN USA ASTM CLASS 1 / CLASS 1 FIRE RATED NASATECH Pure aluminum foil vapor barrier is a crucial component for traditional sauna room construction. Foil vapor barrier will protect the building structure by blocking moisture from getting inside walls and is used by most sauna manufacturers. Optional high temperature foil tape is recommended for best results. Staple foil vapor barrier behind tongue & groove sauna wood paneling on walls and ceiling. It also adds 1R insulation efficiency by reflecting radiant heat back into the sauna room. Foil Vapor Barrier is also commonly used in walls near tub/shower for bathroom remodeling. This is the proper sauna foil vapor barrier made for new construction or remodeled saunas. Foil vapor barrier outlasts plastic vapor barriers which will deteriorate from heat and release gases (and no longer protect walls from moisture). Gain 1R of insulation and the reflective heat efficiency of alum foil radiating behind the paneling. The best heat reflective vapor barrier made for any heated structure. INSTALLATION: NASATECH Aluminum foil vapor barrier is clean, light and easy to install by tacking or stapling. Installs behind sauna wood paneling with reflective side facing in towards you (sauna interior). Overlap seams approx 2-3" inches for effective seal. The best results are achieved by sealing joints with the high-temperature Aluminum Foil Tape (other types of tape will deteriorate from heat).