Which glass is best for home security?

Which glass is best for home security depends on budget and threat level, but best options provide shatter resistance and forced entry deterrence. The top choice is laminated security glass, which consists of two or more glass panes bonded with interlayer of polyvinyl butyral PVB that holds glass together when shattered, similar to car windshield, an intruder must repeatedly strike to create small hole, buying time and making noise. Thickness of at least 6.38 mm laminated is good, 11.5 mm is high security. Second best is tempered laminated glass which combines strength of tempered with holding power of laminated. For highest security, polycarbonate glazing or glass clad polycarbonate is virtually unbreakable and used in high risk homes, but expensive and can scratch. Standard tempered glass is stronger than annealed but shatters completely when broken, so it does not prevent entry as well as laminated. Adding security window film of 8 mil or thicker to existing tempered or annealed glass significantly improves security at lower cost. For best home security, use laminated glass on ground floor windows and doors, double glazed laminated units for energy plus security, with reinforced frames and locks, as glass alone is not enough without strong framing and hardware.