Heat Strengthened Glass vs. Tempered Glass
You might not give much thought to the type of glass used in the windows and doors of buildings, but it’s an important choice. There are two main options for strengthened glass: heat strengthened glass and tempered glass. They could appear to be quite identical at first look. Both go through a heating and cooling process to make the glass stronger. You should be aware of certain significant distinctions nevertheless. At Hawkeye Windows, we understand the significance of this choice, which is why we’re here to guide you through the decision-making process. Let’s explore the pros and cons of each so you know which is the right glass for the job.
What Is Heat Strengthened Glass?
Heat-strengthened glass goes through a process that makes it stronger than regular glass, but not as strong as tempered glass. To heat strengthen glass, it is heated to just below melting point, around 1,100 degrees F, and then cooled at a moderate rate. This alters the glass structure, putting the outer surface into compression and the inner layer into tension. The result is glass that is 2-4 times stronger than regular annealed glass.
Uses of Is Heat Strengthened Glass
While heat-strengthened glass is more durable, it is still not considered safety glass because it can break into large, sharp pieces. It is best used in applications where higher strength is needed but safety glass is not required, such as frameless glass doors, glass countertops, or glass floors.
Some benefits of heat-strengthened glass are:
- Increased strength: The glass can withstand higher loads and impacts without breaking.
- Resistance to thermal stress: The internal stresses make the glass more resistant to thermal shock.
- Reduced deflection: The glass will bend less under its weight.
Here are a few drawbacks of heat-strengthened glass:
- Heat-strengthened glass still breaks into dangerous shards, unlike tempered safety glass.
- The glass may have some visual distortions or imperfections as a result of the rapid cooling process.
- The glass cannot be cut or drilled after the heat-strengthening process. Any modifications must be done beforehand.
So if safety is a concern or the glass needs to be modified after installation, tempered glass is a better choice. But for applications where more strength and durability are priorities and safety glass is not required, heat-strengthened glass can work well. The key is understanding the differences so you can choose the right glass for your needs.
What Is Tempered Glass?
Tempered glass is treated to strengthen it and make it safer to use. The treatment process involves heating the glass to just below the melting point and then rapidly cooling it. This creates tension within the glass that makes it much stronger.
Advantages of Tempered Glass
Tempered glass has some major advantages over heat-strengthened glass:
- It’s 4 to 5 times stronger than heat-strengthened glass of the same thickness. This makes it impact-resistant and less likely to break on impact.
- When it does break, it shatters into small granular pieces instead of sharp shards. Injury risks are considerably decreased as a result.
- It can withstand sudden temperature changes without cracking. This makes it suitable for applications like glass doors, tables, shelving, etc.
- It’s more scratch-resistant than heat-strengthened glass.
Uses of Tempered Glass
Some common uses of tempered glass include:
- Windows – Tempered glass is often used in windows where impact resistance and safety are a concern like doors, sliding doors, windows close to the ground, etc.
- Furniture – Tempered glass is frequently used for table tops, shelving, cabinet doors, etc. Its strength and safety make it ideal for these applications.
- Appliances – Many appliances like ovens, cooktops, refrigerators, etc. use tempered glass for doors and control panels.
- Displays – Tempered glass is used for display cabinets, trophy cases, and other similar fixtures. Its clarity and safety make it a great choice for displays.
Key Differences Between Heat Strengthened Glass vs Tempered Glass
The two most common types of strengthened glass are heat strengthened glass and tempered glass. While they share some similarities in how they’re made, there are a few key differences you should be aware of.
Production Process
The production process for heat-strengthened and tempered glass is largely the same. Glass sheets are heated to just below melting point, around 1,100°F, and then rapidly cooled to strengthen the glass. The difference lies in the speed of the cooling process. Tempered glass is cooled even more rapidly, which allows it to become even stronger.
Strength
Tempered glass can be up to 5 times stronger than regular annealed glass. Heat-strengthened glass provides a strength increase of just 2 to 3 times. So if impact resistance and safety are top priorities, tempered glass is the better choice.
Breakage Pattern
When broken, tempered glass shatters into small granular chunks that are less likely to cause injury. Heat-strengthened glass breaks into larger, shard-like pieces that can still be dangerous. For applications where glass breakage could put people at risk, tempered glass is the safer option.
Uses
Because of its increased strength and safety, tempered glass is often used in locations like doors and windows, skylights, furniture, and appliances. Heat-strengthened glass tends to be used in applications where strength is important but the glass is less likely to break, such as curtain walls or railings. It provides enhanced durability without the higher cost of tempering.
In the end, while heat strengthened and tempered glass share some similar properties, tempered glass is the stronger, safer choice if breakage resistance and impact safety are priorities. For most residential and commercial buildings, tempered glass is worth the investment. But heat-strengthened glass still has its place for less critical applications where strength and cost are a concern.
Conclusion
So there you have it. Now you know the difference between heat-strengthened glass and tempered glass – two types of glass that have been strengthened through heating and cooling to make them safer and more durable. Heat-strengthened glass is almost as strong as tempered glass but won’t shatter into tiny pieces if it breaks. Tempered glass is stronger but will shatter on impact.
In the end, tempered glass and heat-strengthened glass both provide important advantages above the common annealed glass. Before selecting a choice, it’s critical to consider your unique demands, financial limitations, and safety concerns.
If you’re still confused about the type of glass that will work best for your windows, speaking with a specialist at Hawkeye Windows can provide you with advice that is suited to your specific needs.
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