TempShield™ Double Bubble Foil is two layers of 5/32" barrier bubble film laminated between two layers of foil. The highly reflective (97%) foil layer makes TempShield™ a perfect solution for winter-proofing the sidewalls of any greenhouse. A 10.0 R value makes this an affordable permanant solution for insulating metal and commercial buildings, barns or anywhere higher R factors are required.