Annealed Vs Tempered Vs Laminated Glass Differences
Annealed (Non Safety) Plate Glass
Annealed glass gets its name from the process by which it is made- the Annealing Process. The glass is heated above its “annealing point” of 600 degrees and then is cooled at a very slow and controlled rate. Annealed glass, unlike laminated or tempered safety glass, breaks into sharp glass shards that can have devastating results if improperly installed. Annealed glass has the potential to free fall and cut in a similar fashion of a guillotine.
Tempered glass, also referred as “toughened glass,” is plate glass that goes through a special heat & cooling treatment to toughen the glass. The annealed plate glass usually is heated to 1110 degrees then is cooled on the outer surfaces. The cooling pattern causes the outer surfaces to contract faster than the center thus giving the tempered glass its strength.
Tempered glass is considered safety glass because it shatters in a unique way that prevents harm. You can see broken glass with the picture on the left. The glass often shatters or ‘explodes’ into many tiny and dull pieces.
When to Use Tempered Glass
Tempered glass can withstand 5-7 times the amount of pressure than annealed glass, thus it is best used when safety is of concern. Tempered glass can quickly and safely shatter when a situations arises where one has to either escape or be rescued from harm.
Tempered glass is choice for high end retailer’s display cases and storefronts because tempered glass can be created from ultra-clear low-iron glass. Unfortunately glass that has been tempered cannot be cut, therefore it is unwise to choose tempered glass when a non-professional measures the glass. The tempering process generally takes 6-10 business days as the wait time is contingent on how busy the tempering facilities are. We recommend laminated-safety glass when time is of essence.
Laminated glass is a type of safety glass. Rather than shattering like tempered glass, laminated glass maintains its integrity after breaks. Laminated glass is basically a sandwich. It has two sides of glass that sandwiches vinyl- either polyvinyl butyral (PVB) or ethylene-vinyl acetate (EVA). The laminated unit can be made of either annealed or tempered glass.
When to use laminated glass
Laminated Glass maintains its integrity when blunt force is used against it therefore s is great solution when break-in security is a major concern. Examples of laminated glass include storefront doors, windows, and display cases. All windshields are, by law, laminated glass- this prevents shards of glass flying into the car when objects hits the windshield.