The term “tempered glass” is most often mentioned in relation to commercial buildings and maybe in the windows of your house and vehicles. However, with furniture trends gearing towards more modern and minimalistic styles, glass is a popular medium in many furniture pieces, especially with coffee tables.
Coffee tables with glass tabletops that are ¼ inch or ⅜ inch thick are usually made out of tempered glass. However, tabletops that are ½ inch thick are often made out of standard glass, as the extra thickness adds to the strength and durability.
Tempered glass was first developed in the early 1900s by Rudolf Seiden in Austria, and his invention was later improved upon by John Crew in 1905 to create safety glass, to be used in gas masks in WWI. Read on to learn how this war staple is now a requirement for all new and renovated home construction and even for home decor.
How Can You Tell If a Glass Table is Tempered?
At first glance, it is difficult to tell if glass is tempered or not, especially with glass that is more than one inch thick. Just by looking at a piece of glass, you would not necessarily be able to tell whether it was tempered or not.
Luckily, there are a couple of ways to tell if the glass on your coffee table is tempered without actually shattering your table.
Techniques for Spotting Tempered Glass
The first thing to check for is the “bug” or tiny trademark label embedded in the corner of the glass that indicates whether the glass has been through the tempering process. The mark will show the name of the manufacturer and whether it complies with the Consumer Product Safety Commission (GPSC) standards.
Another technique is to examine the edges of the glass and check for any sort of roughness. Due to the additional heating and compression it undergoes, tempered glass usually has completely smooth edges, while standard glass tends to have bumpy or ridged edges.
Tempering does not affect the weight or thickness of the glass and so you do not have to sacrifice safety for comfort. There are also a couple of different options in styling the edges so that can be customized to your tastes are well, such as:
- Seamed Edge
- Pencil Edge
- Flat Edge
- Beveled Edge
A good sign is if there are any slight imperfections on the glass, which indicates that it went through the toughening process, and the imperfections are marks left by the tool utilized in extreme heat. The most common identifiers are any sort of warps, bending, and dimples in the glass.
If you have a polarized lens such as polarized sunglasses handy, use them to examine your glass for any dark spots or lines that occur during the tempering process. If you are also planning on cutting your sheet of glass, try scoring a line on the surface, which should be jagged and flaky if it is real tempered glass.
Should You Buy a Coffee Table with Tempered Glass?
Generally, yes, tempered glass for your coffee table is considered a good investment simply because it is four to six times more durable than regular glass. Tempered glass is less of a safety hazard to families, especially those with young children. Even if the standard glass tabletop is thicker, the tempered glass will still be four to six times more durable.
Your coffee table is likely going to be the centerpiece or at the very least, a defining part of your living room aesthetic. While the standard glass may be easier to mold and may offer more creative options, investing in a tempered glass coffee table ensures that it will stay in your possession for the long run.
What Is Different About Tempered Glass?
Tempered glass is much more common than it used to be, and has expanded outside of cars and buildings. Today, It is used in items such as:
- Cell phone screens
- Refrigerator trays
- Shower doors
If a piece of glass has been tempered, it will break into many granular pieces as opposed to standard glass which will shatter into large jagged shards. These larger pieces are far more likely to cause injury to surrounding individuals because of their sharp edges.
Tempered glass, along with being scratch resistant and harder to break, is less likely to cause injury because it breaks into small pieces with duller edges and it shatters evenly throughout the entire sheet of glass to prevent further injury.
The Cooling Process
The difference between standard glass and tempered glass comes with the different paces of their cooling processes. When exposed to heat, all-glass expands and contracts as it is cooled. To prevent the glass from breaking as it is restored to room temperature, glass undergoes a variety of controlled cooling processes.
Standard glass is made with the annealing process, which slowly releases the internal stress inside the glass and makes it more durable. During the cooling process, the technician can mold the glass into the desired shape and it will hold as it gradually cools down to room temperature.
Different Types of Tempering
Tempered glass is made from annealed glass that has been cut and examined for imperfections that may disrupt the tempering process. The most common way of tempering glass involves heating the glass with a tempering oven and then inflicting it with a high pressing cooling system.
The heated glass is subsequently “quenched” by compressing the glass with high-pressure air nozzles for seconds and as the outer areas of the glass are cooled first, the center of the glass separates from the outer surface and the center will remain in tension white the outer areas enter compression, resulting in increased strength.
Glass can also be tempered chemically, where various chemicals on the surface of the glass are forced to exchange ions to mimic the phenomenon of compression. But this technique is quite uncommon as it is much costlier than utilizing tempering ovens and the quenching process.
There are also many different types of tempered glass that have expanded since its first invention, including:
- Scratch-resistant tempered glass
- Anti-glare tempered glass
- UV Protection glass
- Anti-fingerprint tempered glass
- Matte Screen Guards
- Nano Glass
All of these different variations were designed to serve specific purposes from the automobile to the cellphone industry.
The Difference in Cost and Function
Because tempered glass is significantly stronger than other types of glass, switching to tempered glass can cost an additional $12 to $14 per square foot. Tempered glass is required in some arenas, such as in building codes, where tempered or laminated glass is required for skylights, stairways, elevators, and fire department access panels.
It is also required in passenger vehicles, as the primary function of all tempered glass is safety, and it ensures that the windows will not break into shards in the event of a collision. The tempering also enables the car windows to withstand high temperatures and resist breakage from road debris.
Even though the glass from a coffee table serves a very different function than that of a building or a vehicle, it is one of the pieces in your home that will be subjected to a high level of wear and tear and so durability is a key factor in choosing the right coffee table for you and your family.
Because of the difference in the crafting processes of tempered glass and standard glass, the product will likely also have a different finish and it can be difficult to choose what fits your needs, with the new improvements made with tempered glass, there are many sleek and modern options available.
Choosing the right coffee table for your home may take some time, but it is worth investing the energy into finding the perfect fit for an object that will take its place in the center of your living room. Luckily, there are various tips and tricks to determine the quality of your table and put your mind at ease.