Tempered vs. Annealed Glass: Understanding Safety and Building Codes

When selecting glass for your home or business, safety and durability are critical factors to consider. Two of the most common types of glass used in windows and doors are tempered glass and annealed glass. Understanding the differences between these options can help ensure your home meets safety regulations while providing optimal performance.

What is Annealed Glass?

Annealed glass is the standard type of glass that undergoes a slow cooling process to relieve internal stresses. This controlled cooling strengthens the glass slightly but makes it more susceptible to breaking upon impact. When shattered, annealed glass breaks into large, jagged shards, which can pose a significant safety hazard.

What is Tempered Glass?

Tempered glass, also known as safety glass, is processed through a thermal tempering process. The glass is heated to extreme temperatures and then rapidly cooled, creating internal tension that significantly increases its strength. When broken, tempered glass shatters into small, blunt fragments rather than sharp shards, reducing the risk of severe injuries.

Key Differences Between Tempered and Annealed Glass

1. Strength – Tempered glass is approximately four to five times stronger than annealed glass, making it ideal for high-impact areas.

2. Breakage Pattern – Annealed glass breaks into sharp, dangerous shards, while tempered glass crumbles into small, less harmful pieces.

3. Processing – Annealed glass undergoes slow cooling, while tempered glass is subjected to a rapid heating and cooling process to increase strength.

4. Applications – Tempered glass is required in high-risk areas such as doors, shower enclosures, and windows near floors, while annealed glass is commonly used in general applications like standard window panes.

   
   

   

   Our glass is sourced from Cardinal Glass Industries.

   
   

Safety and Building Code Compliance

Building codes play a crucial role in determining where tempered glass must be used to ensure safety. The International Residential Code (IRC) and International Building Code (IBC) mandate tempered glass in the following situations:

• Doors and Side Panels – Any glass within or adjacent to doors must be tempered to prevent injury upon impact.

• Windows Near Floors – Glass located near walking surfaces must be tempered if it falls within specific height requirements.

• Bathroom Areas – Shower doors, bathtub enclosures, and glass within a certain proximity to water sources must be tempered for added safety.

• Stairways and Railings – Glass used in stairways, railings, and balconies must be tempered to meet safety standards.

  
  

Choosing the Right Glass for Your Home or Business

If safety and durability are top priorities, tempered glass is the superior choice, especially in areas prone to human contact or impact. However, annealed glass may be sufficient for applications where breakage risks are minimal. Understanding the safety regulations and building codes ensures compliance and enhances the overall security of your space.

At NuImage Windows and Doors, we prioritize safety and quality in every installation. Whether you need tempered or annealed glass, our team can help you choose the right option to meet your needs and comply with building codes. Contact us today to learn more about our premium glass solutions!