The Importance of Fire-Rated Glass for Building Safety

Jun 2, 2023 | Fire Doors Safety Insights

Fire-rated glass plays a crucial role in ensuring building safety by providing protection against the devastating effects of fire. With its unique properties, fire-rated glass acts as a barrier, compartmentalizing smoke and flames, and preventing their spread to other areas. This specialized glass is designed to resist fire for extended periods, offering valuable time for occupants to evacuate safely. Whether it’s fire-protective glass that can withstand up to 180 minutes of fire exposure or fire-resistive glass that blocks radiant heat and holds up to 90 minutes of flame resistance, these types of glazing are essential components in meeting building codes and regulations. By choosing the appropriate fire-rated glass, buildings can enhance their overall safety measures and protect occupants from the intense heat and dangers associated with fires.

What is Fire-rated Glass?

Fire-rated glass is a specialized type of glass designed to provide enhanced safety and protection in the event of a fire. This innovative material is engineered to withstand high temperatures and prevent the spread of flames, smoke, and toxic gases throughout a building. In addition to its heat-resistant properties, fire-rated glass also maintains its structural integrity during a fire, helping to compartmentalize the affected area and allowing occupants valuable time to evacuate safely. By incorporating fire-rated glass into a building’s design, architects and engineers can effectively enhance the overall safety and security of the structure, ultimately safeguarding lives and minimizing property damage in the face of potential fire hazards.

Fire-ratings Explained

You’re probably wondering what a fire-rating system even mean. Well-fire-rated glass (also known as fire-resistant glass) is a type of glass that undergoes fire-resistance testing.

A fire rating system, in the context of fire-rated glass, refers to a standardized method of assessing and categorizing the fire resistance capabilities of the glass. It involves subjecting the glass to specific fire-resistance tests to determine its ability to withstand simulated fire conditions, such as high temperatures, for a certain period of time while still maintaining its integrity.

During the testing process, the glass is placed in a test furnace where its performance is closely monitored. The temperature, time, and pressure are controlled to simulate realistic fire conditions. The glass is evaluated based on its ability to resist the spread of flames, smoke, and toxic gases, as well as its capacity to maintain its structural integrity during a fire.

The fire rating system assigns an Integrity Period to the fire-rated glass, which indicates the length of time the glass can remain within its frame without compromising its fire-resistant properties. This information helps architects, engineers, and building owners make informed decisions about incorporating fire-rated glass into their structures to enhance safety and minimize potential fire hazards.

The Integrity Period and the Insulation Period

Highlighting the various categories of fire-rated glass, which is classified based on the time it offers for integrity and insulation, we have the following:

Fire-rated glazing is rated for its ability to remain secure in its frame and fixings, as well as to resist the passage of flames and hot gases when exposed to the heat of a fire. This rating speaks to the integrity of the glass in the face of the flames.

It’s time for the insulation period – the span of time that the glass will serve as a resilient shield against fire, heat, and smoke!

These fire protective levels are broken down into E classifications to denote their performance.

E = glass with an integrity only rating

El = glass with an integrity and insulation rating

EW = glass with an integrity rating and a degree of heat resistance.

Fire-protective Vs. Fire-resistive glass: How they work?

Don’t worry if you’re unsure if your property needs fire-protective glass or fire-resistive glass – they are often used interchangeably, but the differences between the two are significant.

First, we have a fire-protective glass! This specialized glass aims to compartmentalize smoke and flames. 

The fire-protective glass might not stop the passage of radiant heat through to the other side, yet it is capable of resisting fire for up to 180 minutes depending on size as per the International Building Code (IBC).

Fire-protective glass, such as glass ceramics and specialty tempered glass, is typically the go-to choice when it comes to fire-rated doors in accordance with building codes.

The size of the fire-protective glass used in 60 and 90-minute doors in exit enclosures and passageways is limited to a maximum of 100 square inches, regardless of whether or not the building is sprinkled, all in order to protect occupants from the intense heat of a fire while they make their way to safety.

Next up is fire-resistive glass! This type of fire-rated glass contains flame and smoke and blocks radiant heat.

The glass that is fire-resistant can help to protect against the spread of burning heat that may set ablaze materials like paper, curtains, clothing, and other combustible items up to 20 feet away. Such glazing can even hold up to a whopping 90 minutes of flame resistance and is generally regulated as a fire-resistant wall assembly.

During a given time frame, the glazing temperature should not exceed 250°F on the non-fire side. Typically this glass consists of multi-layer fire-resistant layers that, when heated, expand and provide a thermal barrier that holds shattered glass together and prevents the spread of fire, smoke, and intense heat.

Fire Resistive glazing is ideal for larger applications that require a significant level of protection from heat transfer, such as walls requiring a 60-minute or greater fire rating to pass temperature-rise criteria – making them an excellent choice for stairwells, exit access corridors, or any other fire barriers dividing interior construction.

Code Requirements for Fire-Rated Glass

Architects and specifiers should be aware of the main codes related to fire-rated glazing products. These codes provide guidelines and standards for the installation and use of fire-rated glass in buildings. The specific codes may vary depending on the country or region, but some common ones include:

1. International Building Code (IBC): This code is widely used in the United States and provides regulations for building safety, including requirements for fire-rated glazing.

2. National Fire Protection Association (NFPA) codes: NFPA publishes various codes and standards related to fire safety, including NFPA 80 (Standard for Fire Doors and Other Opening Protectives) and NFPA 101 (Life Safety Code), which address fire-rated glazing requirements.

3. European Standards (EN): In Europe, the EN standards specify the performance requirements and testing methods for fire-resistant glazing products.

It is important for architects and specifiers to familiarize themselves with the relevant codes and standards applicable to their specific location. These codes ensure that fire-rated glazing products meet the necessary safety requirements and help enhance the overall fire protection of a building.

Choosing the Right Fire-Rated Glass for Your Building

When it comes to ensuring fire safety in your building, choosing the right kind of fire-rated glass is crucial. Fire-rated glass provides a significant level of protection from heat transfer and can be ideal for larger applications that require a high fire rating. The type of fire-rated glass you select depends on the level of fire protection you need, as well as the specific requirements of your building. There are three classifications of fire-rated glass: E – Integrity, EW – Integrity and low radiation, and EI – Integrity & Insulation. Each classification offers different levels of fire resistance and heat transfer prevention. By selecting the appropriate fire-rated glass, you can enhance evacuation procedures and firefighting efficiency, making it a smart investment for the safety of your building.

Level of Fire Protection

The thickness and size of the fire-rated glass are determined by the type of glazing to be installed; these range from 30/0, 30/30, 60/0, and 60/60. To guarantee optimal evacuation and firefighting efficiency, it is best to opt for fire-rated glass that offers up to one hour of fire protection.

No matter what glazing option you select, the type of glass you use, or most importantly, the quality of the glass, fire safety glass can give you up to four hours of fire protection – making it a smart investment!

Fire Glass Type

Remember there are three classifications of fire-rated glass.

E – Integrity – non-insulating
The fire-resistant capacity of a material to withstand heat on one side without spreading the flames or hot gases is a significant factor in providing a physical shield to inhibit the fire from spreading.

EW – Integrity and low radiation This is the ability of glass to not break and thus preventing the passage of an active flame and limiting heat transfer.

EI – Integrity & Insulation
This is the ability of glass to withstand fire exposure on one side without transmitting the flame to the unexposed side. This also has the ability to limit heat transfer thanks to conduction, convection, or radiation (in addition to integrity). It also allows the the non-affected side of a space t to maintain a mean temperature of 140 °C and a maximum temperature of 180 °C on the non-fire side of construction.

Choose the Best Fire-rated Glass for your Commerical Doors.


Fire-rated glass is a must-have for any building that needs to prioritize safety and security. Its unique properties provide effective fire protection, allowing occupants to evacuate safely in case of an emergency. With its various types and ratings, fire-rated glass can be tailored to meet the needs of a particular building. Investing in the right fire-rated glass is a great way to ensure the safety of your building, so contact a professional today to learn more about your options.

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