What type of glass is used in commercial storefront doors?
Tempered glass is the standard glass type for commercial storefront doors. Tempered glass is approximately ten times stronger than standard annealed glass and breaks into small, rounded pebbles rather than sharp shards, qualifying it as safety glass under ANSI Z97.1 and CPSC 16 CFR 1201. For applications requiring additional performance, laminated glass provides impact resistance and security, while insulated glass units provide thermal performance for energy code compliance.
What is the difference between narrow stile, medium stile, and wide stile storefront doors?
The stile is the vertical framing member on each side of the door. Narrow stile doors (2-1/4” to 3”) maximize glass area but accept limited hardware. Medium stile doors (3-1/2” to 4-1/2”) balance glass area with broader hardware compatibility and are the most commonly specified type. Wide stile doors (5” and wider) accommodate the full range of commercial hardware including exit devices and are required for high-traffic and code-required exit locations.
Can storefront doors be fire-rated?
Standard aluminum storefront doors are not fire-rated. When a fire rating is required, the opening must use a hollow metal (steel) door and frame assembly with fire-rated glass. Fire-rated assemblies are available at 20-minute, 45-minute, 60-minute, 90-minute, and 3-hour (180-minute) levels. All components in a fire-rated assembly, including the door, frame, glass, and hardware, must carry matching fire labels.
What glass is required for a fire-rated door?
Fire-rated doors require glass that carries a fire rating equal to or greater than the door assembly rating. Acceptable fire-rated glass types include fire-rated ceramics, fire-rated laminated glass, and wired glass. Wired glass is restricted to non-impact locations by current building codes because it does not meet safety glazing standards. The maximum glass size decreases as the fire rating increases. Doors with 90-minute ratings are typically limited to 100 square inches of glass per lite, and 3-hour (180-minute) rated doors generally do not permit any glass.
When should I use a storefront door instead of a hollow metal door?
Use a storefront door when the opening is an exterior entrance or retail-facing facade, maximum glass visibility is the design intent, no fire rating is required, and the door integrates with an aluminum storefront or curtain wall system. Use a hollow metal door with a lite kit when the opening requires a fire rating, higher physical security is needed, or the door is in an interior corridor, stairwell, or other rated wall assembly.
What is tempered glass and why is it used in storefront doors?
Tempered glass is manufactured through extreme heating followed by rapid cooling, which increases its strength to approximately ten times that of standard annealed glass. When tempered glass breaks, it shatters into small, rounded pebbles without sharp edges, which is why it is classified as safety glass. Tempered glass is required by code in all glazing locations where human impact is possible, including doors, sidelites, and glass panels near floor level. It is the standard and most cost-effective glass type for non-fire-rated storefront door applications.
