Safety glass is a welcome feature in modern home construction—it breaks into tiny pieces as opposed to large shards. So, it is less harmful when it shatters than regular plate glass, which can form large, dangerous shards. In the video above, Ask This Old House general contractor Tom Silva demonstrates the striking difference between safety glass and regular glass when broken.
Understanding Safety Glass
Safety glass is a type of glass that has been treated or manufactured to be more resistant to breaking and to reduce the risk of injury when it does break. Understanding the different types of safety glass will help homeowners make informed decisions for their properties.
Tempered Glass
Tempered glass is created through a process of extreme heating and rapid cooling, which strengthens the glass and changes its properties when it shatters. Here are some features that define tempered glass:
- Four times stronger than regular glass
- Breaks into small, cube-like pieces instead of sharp shards
- Common in shower doors, sliding glass doors, and windows near floor-level
Laminated Glass
Laminated glass consists of two or more layers of glass with a plastic interlayer sandwiched between them. It holds together when shattered, reducing the risk of falling glass and providing additional sound insulation. Car windshields and skylights typically use this glass.
Benefits of Safety Glass
Safety glass offers several advantages over regular glass—and you have to install it in certain areas of your home per local building codes.
Enhanced Safety
The primary benefit of safety glass is its ability to reduce the risk of injury. When it breaks, it forms small, relatively harmless pieces instead of large, sharp shards that can cause severe cuts. This feature is particularly beneficial in homes with children and pets, or in areas where you are more likely to bump or fall into a window.
Increased Durability
Safety glass is more resistant to impacts and temperature changes, making it less likely to break in the first place. This durability is useful in areas prone to severe weather or high traffic. For instance, windows in storm-prone regions will benefit greatly from the improved durability of safety glass.
Improved Security
Some types of safety glass, particularly laminated glass, provide an additional layer of security against break-ins. The plastic interlayer makes it more difficult for intruders to gain entry through windows or glass doors.
Where Safety Glass is Required
Building codes often require the use of safety glass in specific areas of the home to minimize injury risks. Some common locations include:
- Windows within 24 inches of a door
- Windows that extend to within 18 inches of the floor
- Shower and tub enclosures
- Glass panels near staircases
- Skylights
- Large picture windows
It’s important to consult local building codes or a professional contractor to ensure compliance with safety glass requirements in your area.
Installing Safety Glass
While installing safety glass is typically a job for professionals, understanding the process can help homeowners make informed decisions:
- Measure the opening accurately.
- Order custom-cut safety glass from a reputable supplier.
- Remove the old glass carefully, wearing protective gear.
- Clean the frame thoroughly.
- Apply glazing tape or compound to the frame.
- Insert the new safety glass.
- Secure the glass with glazing points or stops.
- Apply additional glazing compound if necessary.
- Clean and inspect the installation.
We recommend professional installation to ensure proper fit and compliance with building codes. A skilled installer will also be able to address any unforeseen challenges that might arise during the installation process.
Identifying Safety Glass
Knowing how to identify safety glass can be useful for homeowners:
- Look for a permanent etching in the corner of the glass
- Tempered glass often has a slightly distorted reflection
- Laminated glass may have a visible plastic layer when viewed from the edge
If you’re unsure whether a piece of glass in your home is safety glass, consult a professional for verification.
Maintaining Safety Glass
While safety glass is durable, proper maintenance can extend its lifespan and effectiveness:
- Clean regularly with non-abrasive cleaners
- Inspect for chips or cracks periodically
- Replace damaged safety glass right away to maintain its protective properties
- Avoid placing heavy objects against safety glass windows or doors
Special Considerations
When maintaining safety glass, you need to consider any additional treatments or coatings that may have been applied to the glass. For example, some safety glass options come with low-emissivity (Low-E) coatings to improve energy efficiency. If your glass has such coatings, be sure to use appropriate cleaning methods to avoid damaging these treatments.
Our Conclusion
Most local building codes require safety glass in several areas of modern homes, providing protection against injuries from broken glass. Its ability to break into small, less harmful pieces, as shown in the video, makes it a vital part of areas prone to impacts or accidents. While it has a higher cost, the peace of mind and enhanced safety it offers make safety glass a worthwhile investment for any homeowner.
By understanding the different types of safety glass, where it is required, and how it can benefit your home, you can make an informed decision that improves both the safety and value of your property.