The ImpactGard window system includes laminated glass, which has an interlayer sandwiched between two sheets of glass to deliver extra impact resistance. The interlayer is 100 times more rigid than the industry standard, according to the manufacturer, so it delivers five times the tear strength. Even if the glass cracks under pressure, the fragments will adhere to the interlayer. The insulated version also uses a low-E coating. 800-535-3936. www.jeld-wen.com.