Laminated Glass: Definition & Meaning

Laminated Glass

Safety glass made by bonding two or more glass panes around an interlayer of polyvinyl butyral (PVB) film, so that when broken, the fragments stay adhered to the film rather than scattering.

2 min read · Updated March 2026

Definition

Safety glass made by bonding two or more glass panes around an interlayer of polyvinyl butyral (PVB) film, so that when broken, the fragments stay adhered to the film rather than scattering.

Laminated glass is made by permanently bonding two sheets of glass around a polyvinyl butyral (PVB) interlayer under heat and pressure. The PVB film is the key: when laminated glass breaks, the fragments adhere to the interlayer rather than scattering as dangerous shards. The glass may crack extensively, but the pane holds together — making it a critical safety and security product.

Laminated vs. Tempered Glass

Property	Laminated	Tempered
Break pattern	Cracks but stays in frame	Shatters into small cubes
Security	Excellent (intruder must hit repeatedly)	Poor (single blow shatters)
Sound reduction	Good (PVB dampens vibration)	Minimal added benefit
UV blocking	99%+ (PVB blocks UV)	No UV benefit
Hurricane/impact	Yes (with impact-rated PVB)	No (not impact rated)
Cost	Higher	Moderate

Where Laminated Glass is Used

Skylights and overhead glazing — required by code; prevents injury from falling glass if broken
Hurricane/impact windows — heavy-duty PVB interlayer resists penetration by wind-borne debris
Security glazing — multiple laminations create forced-entry resistance
Acoustic windows — PVB interlayer significantly reduces sound transmission (STC improvement of 3–5 points)
UV-sensitive applications — museums, art galleries, and homes with valuable furnishings benefit from the 99%+ UV blocking

Laminated Glass in IGUs

Laminated glass can be combined with the double-pane IGU format — typically as the interior pane — to combine thermal insulation with safety, security, and sound attenuation in a single unit.