SmartFOIL- 4ft x 250ft Industrial Grade Radiant Barrier 1000 sq. ft roll - Attic Foil, House Wrap, Reflective Insulation - Perforated, Breathable - Engineered FOIL (Blocks 95% of Radiant Heat) Unlike traditional mass insulations like blown-in and batt cellulose/fiberglass, SmartFOIL radiant barrier blocks 95% of the radiant heat, thereby greatly reducing the amount of heat that enters a home when installed in the attic space or as a house wrap. Combined with existing mass insulation, you can significantly improve the comfort of your home, and SAVE BIG on YOUR ELECTRIC BILLS. Product works equally well in both hot and cold environment!!! Non-toxic; non-carcinogenic; fiber free; easy to install; not affected by humidity; maintenance free; does not promote the growth of fungi or bacteria; does not support nesting by rodents or insects. FIRE RATING: Class A / Class 1 (ASTM E-84) - Meets fire and smoke requirements for most local, state and federal building codes MEETS OR EXCEEDS ALL ASTM C1313 STANDARDS - Class A Fire Rating (E84 with E2599 mounting). Corrosion resistance according to D3310 is achieved by a proprietary clear coating applied to the Engineered Foil surface.INDUSTRIAL / COMMERCIAL GRADE - SmartFOIL Radiant Barrier is TEAR & PUNCTURE PROOF, but you can easily cut it with utility scissors. Both sides reflects 95% of the radiant heat.PAYS FOR ITSELF - by reducing heating cost in winter and cooling cost in summer. Blocks 95% heat radiating from the underside of a hot roof. Save big on your utility bill.EASY TO INSTALL - in existing homes or new constructions, by stapling to the bottom of rafters and over attic floor. Frequently used as House Wrap for additional insulation. Also used in barns, metal buildings, and poultry houses.1,000 SQUARE FEET ROLL - 4 feet x 250 feet BREATHABLE, PERFORATED, DOUBLE-SIDED Engineered Foil radiant barrier.