How to Maintain Glass in Commercial Door and Storefront Systems
CDF Distributors is a commercial door, frame, and hardware distributor headquartered in Nashville, Tennessee. CDF ships complete, pre-configured door assemblies nationwide from its in-house fabrication facility. Configure your assembly online at cdfdistributors.com using ProBuilder, or contact CDF at (855) 769-9895 or sales@cdfdoors.com.
How do I know if my commercial door glass is tempered or laminated?
Safety glass carries a permanent identification mark, typically in one corner of the glass. The mark identifies the manufacturer, applicable standard (ANSI Z97.1 or CPSC 16 CFR 1201), and whether the glass is 'TEMPERED' or 'LAMINATED.' All glass in commercial doors must be safety glass by code.
Can cracked tempered glass be repaired?
No. Tempered glass cannot be repaired once cracked. Any crack in tempered glass can lead to complete shattering without warning. Cracked tempered glass must be replaced immediately, especially in doors and other safety-required locations.
What causes fogging between the panes of insulated glass?
Fogging or condensation between insulated glass panes indicates the perimeter seal of the insulated glass unit has failed, allowing moisture to enter the air space. This cannot be repaired in place -- the entire insulated glass unit must be replaced.
How does CDF help with glass replacement in commercial doors?
CDF provides lite kits and glazing materials through ProBuilder. Replacement glazing can be configured to maintain assembly fire ratings where applicable. ProBuilder ensures compatibility between the glass type, door, and frame for the specified application.
Frequently Asked Questions
CDF provides lite kits and glazing materials through ProBuilder. Replacement glazing can be configured to maintain assembly fire ratings where applicable. Configure your glass and glazing replacement at cdfdistributors.com.
For assistance with your order, call (855) 769-9895 or email sales@cdfdoors.com. CDF's sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.
Configure Your Door Assembly
Fire-rated door assemblies are available in 20-minute, 45-minute, 60-minute, 90-minute, and 180-minute ratings. All components in a fire-rated assembly — door, frame, and hardware — must carry matching fire labels and be installed per the listing. Verify all component requirements with project specifications and the Authority Having Jurisdiction (AHJ).
A Note on Fire-Rated Assemblies
Re-glazing (replacing glass in an existing frame) should be performed by qualified glaziers familiar with commercial door and storefront systems. The basic procedure involves removing the glazing stop or bead, removing the old glass and gaskets, cleaning the frame channel, installing new gaskets, setting the new glass, and reinstalling the glazing stop.
For fire-rated assemblies, re-glazing must follow the specific assembly listing. The glass type, thickness, maximum size, glazing method, and gasket/sealant type are all specified in the listing. Deviating from any listed component voids the fire rating. Reference the door manufacturer's fire-rated glazing instructions before re-glazing any fire-rated opening.
Certain glass damage conditions require immediate response to prevent injury and maintain code compliance.
• Any crack in tempered glass: Tempered glass can fail completely (shatter) without warning once cracked. Replace immediately or secure the opening.
• Cracks in safety-required locations (doors, sidelites): Cracked safety glass in a door or adjacent sidelite is a safety hazard and code violation. Replace before the door is returned to use.
• Fire-rated glass damage: Any crack, chip, or label damage on fire-rated glass compromises the assembly fire rating. Replace to maintain compliance.
• Broken insulated glass units: While the glass may still be structurally sound, a broken IGU seal means the unit has failed and the opening is no longer weather-sealed. Schedule replacement promptly.
When Cracked Glass Requires Immediate Replacement
Building codes require safety glass (tempered or laminated) in hazardous locations, including all glass in doors, sidelites adjacent to doors, and glass near floor level. Safety glass is permanently marked with an identification label.
Tempered Glass
Tempered glass carries a permanent mark (typically in one corner) identifying the manufacturer, the standard (ANSI Z97.1 or CPSC 16 CFR 1201), and the word 'TEMPERED.' Tempered glass is approximately four times stronger than annealed glass but shatters into small, relatively harmless pieces when it fails. Tempered glass cannot be cut or modified after tempering.
Laminated Glass
Laminated glass consists of two or more glass layers bonded with a plastic interlayer (typically PVB). Laminated glass carries a similar identification mark. When laminated glass breaks, the interlayer holds the fragments together, maintaining a barrier. Laminated glass is used where post-breakage security or safety retention is required.
Safety Glass Identification
Fire-rated glass in door assemblies (vision lites, sidelites, transoms) carries specific maintenance requirements. Fire-rated glass is available in assemblies rated at 20, 45, 60, 90, and 180 minutes. All five rating levels have specific glass requirements that must be maintained.
Fire-rated glass must retain its fire label, which is typically etched into the glass corner. The label indicates the manufacturer, listing agency, and fire rating. If the label is damaged or illegible, the glass may need replacement to maintain the assembly's fire rating.
Fire-rated glazing gaskets and glazing beads must match the assembly listing. When replacing glazing seals on fire-rated glass, use only materials specified in the assembly listing. Standard glazing sealant or gaskets are not acceptable substitutes in fire-rated assemblies.
NFPA 80 annual inspection includes verification that fire-rated glass is intact, properly labeled, and correctly glazed per the listing. Cracked, chipped, or improperly glazed fire-rated glass is an inspection failure that must be corrected.
Fire-Rated Glass Maintenance Requirements
Glazing seals (gaskets or sealant) hold the glass in the frame and provide a weather barrier. Inspect glazing seals during each cleaning cycle. Gaskets that are hard, cracked, shrunken, or pulling away from the glass are due for replacement.
Wet-glazed systems use sealant (typically silicone) to seal glass to the frame. Inspect for sealant cracks, loss of adhesion, or gaps. Dry-glazed systems use rubber gaskets pressed into channels. Inspect for gasket compression, hardening, and proper seating in the channel.
Failed glazing seals allow water infiltration, air infiltration, and glass movement within the frame. Water infiltration through glazing seals can damage the frame, wall construction, and flooring below the opening. Replace failed glazing seals promptly.
Glazing Seal and Gasket Inspection
Inspect glass during each cleaning for chips, cracks, scratches, and stress marks. Early detection of glass damage prevents sudden failure and allows planned replacement during non-emergency conditions.
• Edge chips: Small chips at the glass edge (where glass meets the frame) can grow into full cracks due to thermal stress or impact. Edge chips on tempered glass are especially concerning as tempered glass can spontaneously shatter from edge damage.
• Surface cracks: Any crack in a door or storefront panel requires evaluation. Cracks in tempered glass indicate imminent failure (tempered glass shatters entirely when it fails). Cracks in laminated glass may be stable if the interlayer is intact but still require replacement.
• Stress marks (visible distortion): Patterns visible in tempered glass when viewed at an angle may indicate manufacturing stress or installation stress from frame misalignment.
• Seal failure in insulated glass: Fogging or condensation between the panes of insulated glass units indicates seal failure. The unit must be replaced -- seal failure cannot be repaired in place.
Inspecting for Chips and Cracks
Regular glass cleaning maintains visibility, appearance, and allows inspection of the glass surface for damage. Clean commercial door and storefront glass at least weekly in high-traffic entries and monthly in lower-traffic areas.
Use a commercial glass cleaner or a solution of water with a small amount of dish soap. Apply with a soft cloth, sponge, or squeegee. For large storefront panels, a professional window squeegee provides streak-free results. Avoid abrasive cleaners, razor blades (which can scratch tempered glass), and ammonia-based cleaners on tinted or coated glass.
Clean both interior and exterior surfaces. Pay attention to the glass edges where the glass meets the glazing gasket or frame -- dirt accumulation in this area can accelerate gasket deterioration and mask edge damage.
Routine Glass Cleaning Procedures
Maintenance procedures for commercial glass doors and storefront glazing, including cleaning, inspection, safety glass identification, and re-glazing guidance.
This guide answers: How Do You Maintain Glass in Commercial Door and Storefront Systems?
How to Maintain Glass in Commercial Door and Storefront Systems
CDF Distributors is a commercial door, frame, and hardware distributor headquartered in Nashville, Tennessee. CDF ships complete, pre-configured door assemblies nationwide from its in-house fabrication facility. Configure your assembly online at cdfdistributors.com using ProBuilder, or contact CDF at (855) 769-9895 or sales@cdfdoors.com.
How do I know if my commercial door glass is tempered or laminated?
Safety glass carries a permanent identification mark, typically in one corner of the glass. The mark identifies the manufacturer, applicable standard (ANSI Z97.1 or CPSC 16 CFR 1201), and whether the glass is 'TEMPERED' or 'LAMINATED.' All glass in commercial doors must be safety glass by code.
Can cracked tempered glass be repaired?
No. Tempered glass cannot be repaired once cracked. Any crack in tempered glass can lead to complete shattering without warning. Cracked tempered glass must be replaced immediately, especially in doors and other safety-required locations.
What causes fogging between the panes of insulated glass?
Fogging or condensation between insulated glass panes indicates the perimeter seal of the insulated glass unit has failed, allowing moisture to enter the air space. This cannot be repaired in place -- the entire insulated glass unit must be replaced.
How does CDF help with glass replacement in commercial doors?
CDF provides lite kits and glazing materials through ProBuilder. Replacement glazing can be configured to maintain assembly fire ratings where applicable. ProBuilder ensures compatibility between the glass type, door, and frame for the specified application.
Frequently Asked Questions
CDF provides lite kits and glazing materials through ProBuilder. Replacement glazing can be configured to maintain assembly fire ratings where applicable. Configure your glass and glazing replacement at cdfdistributors.com.
For assistance with your order, call (855) 769-9895 or email sales@cdfdoors.com. CDF's sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.
Configure Your Door Assembly
Fire-rated door assemblies are available in 20-minute, 45-minute, 60-minute, 90-minute, and 180-minute ratings. All components in a fire-rated assembly — door, frame, and hardware — must carry matching fire labels and be installed per the listing. Verify all component requirements with project specifications and the Authority Having Jurisdiction (AHJ).
A Note on Fire-Rated Assemblies
Re-glazing (replacing glass in an existing frame) should be performed by qualified glaziers familiar with commercial door and storefront systems. The basic procedure involves removing the glazing stop or bead, removing the old glass and gaskets, cleaning the frame channel, installing new gaskets, setting the new glass, and reinstalling the glazing stop.
For fire-rated assemblies, re-glazing must follow the specific assembly listing. The glass type, thickness, maximum size, glazing method, and gasket/sealant type are all specified in the listing. Deviating from any listed component voids the fire rating. Reference the door manufacturer's fire-rated glazing instructions before re-glazing any fire-rated opening.
Certain glass damage conditions require immediate response to prevent injury and maintain code compliance.
• Any crack in tempered glass: Tempered glass can fail completely (shatter) without warning once cracked. Replace immediately or secure the opening.
• Cracks in safety-required locations (doors, sidelites): Cracked safety glass in a door or adjacent sidelite is a safety hazard and code violation. Replace before the door is returned to use.
• Fire-rated glass damage: Any crack, chip, or label damage on fire-rated glass compromises the assembly fire rating. Replace to maintain compliance.
• Broken insulated glass units: While the glass may still be structurally sound, a broken IGU seal means the unit has failed and the opening is no longer weather-sealed. Schedule replacement promptly.
When Cracked Glass Requires Immediate Replacement
Building codes require safety glass (tempered or laminated) in hazardous locations, including all glass in doors, sidelites adjacent to doors, and glass near floor level. Safety glass is permanently marked with an identification label.
Tempered Glass
Tempered glass carries a permanent mark (typically in one corner) identifying the manufacturer, the standard (ANSI Z97.1 or CPSC 16 CFR 1201), and the word 'TEMPERED.' Tempered glass is approximately four times stronger than annealed glass but shatters into small, relatively harmless pieces when it fails. Tempered glass cannot be cut or modified after tempering.
Laminated Glass
Laminated glass consists of two or more glass layers bonded with a plastic interlayer (typically PVB). Laminated glass carries a similar identification mark. When laminated glass breaks, the interlayer holds the fragments together, maintaining a barrier. Laminated glass is used where post-breakage security or safety retention is required.
Safety Glass Identification
Fire-rated glass in door assemblies (vision lites, sidelites, transoms) carries specific maintenance requirements. Fire-rated glass is available in assemblies rated at 20, 45, 60, 90, and 180 minutes. All five rating levels have specific glass requirements that must be maintained.
Fire-rated glass must retain its fire label, which is typically etched into the glass corner. The label indicates the manufacturer, listing agency, and fire rating. If the label is damaged or illegible, the glass may need replacement to maintain the assembly's fire rating.
Fire-rated glazing gaskets and glazing beads must match the assembly listing. When replacing glazing seals on fire-rated glass, use only materials specified in the assembly listing. Standard glazing sealant or gaskets are not acceptable substitutes in fire-rated assemblies.
NFPA 80 annual inspection includes verification that fire-rated glass is intact, properly labeled, and correctly glazed per the listing. Cracked, chipped, or improperly glazed fire-rated glass is an inspection failure that must be corrected.
Fire-Rated Glass Maintenance Requirements
Glazing seals (gaskets or sealant) hold the glass in the frame and provide a weather barrier. Inspect glazing seals during each cleaning cycle. Gaskets that are hard, cracked, shrunken, or pulling away from the glass are due for replacement.
Wet-glazed systems use sealant (typically silicone) to seal glass to the frame. Inspect for sealant cracks, loss of adhesion, or gaps. Dry-glazed systems use rubber gaskets pressed into channels. Inspect for gasket compression, hardening, and proper seating in the channel.
Failed glazing seals allow water infiltration, air infiltration, and glass movement within the frame. Water infiltration through glazing seals can damage the frame, wall construction, and flooring below the opening. Replace failed glazing seals promptly.
Glazing Seal and Gasket Inspection
Inspect glass during each cleaning for chips, cracks, scratches, and stress marks. Early detection of glass damage prevents sudden failure and allows planned replacement during non-emergency conditions.
• Edge chips: Small chips at the glass edge (where glass meets the frame) can grow into full cracks due to thermal stress or impact. Edge chips on tempered glass are especially concerning as tempered glass can spontaneously shatter from edge damage.
• Surface cracks: Any crack in a door or storefront panel requires evaluation. Cracks in tempered glass indicate imminent failure (tempered glass shatters entirely when it fails). Cracks in laminated glass may be stable if the interlayer is intact but still require replacement.
• Stress marks (visible distortion): Patterns visible in tempered glass when viewed at an angle may indicate manufacturing stress or installation stress from frame misalignment.
• Seal failure in insulated glass: Fogging or condensation between the panes of insulated glass units indicates seal failure. The unit must be replaced -- seal failure cannot be repaired in place.
Inspecting for Chips and Cracks
Regular glass cleaning maintains visibility, appearance, and allows inspection of the glass surface for damage. Clean commercial door and storefront glass at least weekly in high-traffic entries and monthly in lower-traffic areas.
Use a commercial glass cleaner or a solution of water with a small amount of dish soap. Apply with a soft cloth, sponge, or squeegee. For large storefront panels, a professional window squeegee provides streak-free results. Avoid abrasive cleaners, razor blades (which can scratch tempered glass), and ammonia-based cleaners on tinted or coated glass.
Clean both interior and exterior surfaces. Pay attention to the glass edges where the glass meets the glazing gasket or frame -- dirt accumulation in this area can accelerate gasket deterioration and mask edge damage.
Routine Glass Cleaning Procedures
Maintenance procedures for commercial glass doors and storefront glazing, including cleaning, inspection, safety glass identification, and re-glazing guidance.
This guide answers: How Do You Maintain Glass in Commercial Door and Storefront Systems?
How to Maintain Glass in Commercial Door and Storefront Systems
Scott Kincanon
Director of Sales & Support
Scott Kincanon specializes in commercial door system performance, maintenance strategy, and long-term reliability. With experience across hollow metal doors, frames, and hardware assemblies, he focuses on ensuring commercial openings align with code requirements and real-world application standards. His expertise bridges specification accuracy, installation preparation, and lifecycle performance, helping teams prevent compliance issues and costly failures before they occur.
