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We always want our homes to be safe places, especially when making home improvements. The kitchen is an area in which safety concerns are at the forefront of our minds. You've likely heard how tempered glass can, at times, be safer than untreated glass or other alternatives. Should the kitchen windows be tempered? We've done some research and have some great information for you.
Kitchen windows should be tempered if all of the following criteria are met:
- The window is more than 9 square feet in one solid sheet of glass
- The glass is 18 inches or less from the floor
- The top of the glass is greater than 36 inches above the floor
- There is a 36-inch walkway on either side of the glass
Only if all these factors are met for one window do building codes dictate the glass must be tempered.
Now that you know your kitchen windows don't have to be tempered unless meeting specific criteria, let's discuss what tempered glass actually is and go over its benefits. We'll answer some additional questions you might have as well. Keep reading!
What makes glass tempered?
Tempered glass is also known as safety glass. Once the glass is tempered, it falls into many small pieces instead of large shards with jagged edges. Because the pieces are small, they have less chance of hurting someone when the glass breaks. Although the small pieces of glass are still sharp, they don't have the same amount of force and weight behind them in the event of glass breaking. Tempered glass is also more resistant to breaking than annealed or regular glass.
Glass becomes tempered when it is heated to extremely high temperatures, generally above 600 degrees celsius, and then undergoes a high-pressure cooling procedure. The cooling procedure is called quenching. Quenching is accomplished by directing high-pressure blasts of cold air onto the surface of the glass. The center of the glass is the last to cool. As the glass lowers in temperature, it tries to pull back from its outer surfaces. Because of this, the center remains in tension while the outer edges go into compression.
What are the advantages of tempered glass?
The primary advantage of tempered glass is the extra strength it brings to your windows. A tempered glass window's surface is less likely to break should stray gravel be thrown during mowing or if there are any accidents in the kitchen. Additionally, if enough force is applied for the window to break, it will fall into small, less harmful pieces instead of jagged shards being projected. Tempered glass is also more resistant to higher temperatures than annealed glass. Overall, tempered glass is at least four times stronger than regular glass.
Tempered glass is also non-toxic, and the extreme heat to which the glass is exposed cleanses the surface of any pollutants, making it a healthy choice for your home.
Does tempered glass have any disadvantages?
Although tempered glass benefits generally outweigh the disadvantages, there are a few important things to consider when deciding if tempered glass is for you.
Tempered glass cannot be resized. The piece of glass has to be cut to size before the tempering process. If any cuts are attempted after the heating and cooling, the glass will most assuredly shatter. With that, it's important to note that any damage to the outside edges of the tempered glass will cause it to break.
Additionally, the tempered glass surface can sometimes appear a little wavy -- some might be bothered by this look if their particular piece of glass has obvious waves.
It's also absolutely worth mentioning that tempered glass has been known to shatter without seemingly any outside manipulation. Many might see a mystery as to why tempered glass spontaneously breaks, but the usual culprit is some unseen damage to the outside edges of the glass that generally occurs during the manufacturing, shipping, or installation process.
Where does tempered glass work best?
Tempered glass works best in places where slips and falls are most likely to happen, such as bathrooms and kitchens. Any room where the floor could get damp would be best served by having windows and glass doors made of tempered glass. Not only is tempered glass the safe option for kitchen windows and shower doors, but it is also a popular option for vehicle windshields.
How do you tell if a window is tempered?
Most tempered glass comes with an etch mark indicating it is tempered. If this mark isn't visible, closely inspect the surface of the glass. Tempered glass can have waves or irregularities across its surface. At times, the waves can be difficult to spot.
Tempered glass often has smooth, even edges that are due to all the polishing and inspection the glass must go through. If the edges are rounded, the glass is almost definitely tempered.
A surefire way to tell if the glass is tempered is by viewing it through polarized glasses with a bright light shining through it. Through the polarized glasses, tempered glass will show black streaks through the surface.
Is tempered glass stronger than annealed?
Annealed glass, which is another word for regular glass processed for commercial use, is created by a cooling process during the manufacturing process. Because it isn't heated and cooled, it is not considered tempered glass. Tempered glass is at least four times stronger than regular annealed glass due to the tempering process.
Does your window trim need updating? Read our post, "How to Paint Window Frames?"
Is tempered glass stronger than laminated glass?
Laminated glass is made of two or more panes of annealed glass joined together by a plastic layer. Because it is layered and held together by plastic, the laminate glass holds its shape even if it shatters.
Tempered glass is stronger than laminated glass, though not as safe. Although the glass is more resistant to breaking, the small pieces tend to scatter everywhere when tempered glass breaks. Laminated glass will hold its shape, making it less likely to cause small cuts than tempered glass.
Are tempered glass windows expensive?
Tempered glass windows are definitely more expensive than annealed glass windows but not quite as expensive as laminated glass. In general, tempered glass is about three times more expensive than regular glass.
To read more about window pricing, check out our post, "How Much Does a Living Room Window Cost?"
Kitchen windows don't have to be tempered unless they meet specific criteria. Although not required, there are many benefits to installing tempered glass as opposed to regular, annealed glass. If given the opportunity, take your time researching all safety glass options and make the best choice for the benefit of you and your family.