Welcome to Plano Bath & Glass, where we try to answer all of your glass-related questions. As always, if you can not find the answer to your question here in our database, feel free to contact us.
The glass in my fireplace (or showcase or table top) was fine for years and one day it just exploded. Was it defective?
No, the glass probably was not defective. Most likely it was tempered glass (that is glass that has been heated then cooled quickly to strengthen it) which, on occasion, can undergo spontaneous breakage.
The same process that makes tempered glass so strong also makes it vulnerable to this type of breakage. The same process that strengthens tempered glass also creates some inherent problems. Through the tempering process, a system of residual stresses is introduced to convert normal flat glass to safety glass when the stress level is high enough. Glass is tempered by heating sized, edged glass in a tempering furnace to approximately 1,200 degrees F, then rapidly cooling, or quenching, the glass to approximately 400 to 600 degrees F. In quenching, air jets quickly cool and set the surfaces, leaving the inner portion of the glass thickness relatively hot and cooling at a slower rate. The surfaces become rigid, but the center is still pliable and contracting as it cools, thus compressing the surface. Compressive residual stresses imposed on the glass surface, which close up any cracks, are balanced by residual tensile stress in the center of the glass.
These stresses make tempered glass approximately four times stronger than annealed glass, making it ideal for applications where maximum resistance to thermal and cyclic wind loading pressures is required. In addition, if broken, fully tempered glass breaks into relatively safe, small pieces, rather than shards. However, distortion and point inclusions are a natural part of the tempering process. Your quality glass company can assess the situation for you.
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The glass in my door broke and the glass shop won't sell me a piece of plate glass to replace it. The manager says I need to buy "safety glass." Is he trying to cheat me?
No, but he may be saving your life - or keeping you out of legal trouble. You may not know that glass is one of the few building materials actually regulated by the Federal government and that usage of glass in and near doors falls under strict Consumer Product Safety Commission rules. Quality glass shops know that all glass in doors must meet the requirements of CPSC 16 CFR 1201 safety glazing - which generally means that either tempered or laminated glass or plastic must be used.
When a glass shop won't sell you a certain type of glass for a particular application, it is usually with your safety in mind. In this case, it would be illegal for either the glass shop--or the homeowner--to install non-safety glass in that door. This becomes an issue when the door is old and was manufactured before the safety glazing laws took place.
While the CPSC regulates safety glass usage in and near doors, building codes regulate what types of glass can be used in other hazardous locations. Many codes require safety glass below a certain height, in areas with a lot of water and potential for slippage such as hot tub enclosures, on stair wells or in other hazardous locations.
Safety glass is more expensive than "plate glass," but the benefits you'll receive in terms of that safety and peace of mind will be well-worth the expense.
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Where can I buy burglar-proof glass?
You can't. There is no such thing as burglar-proof glass, but there is burglar-resistant glass. Burglar-resistant glass is stronger than plain annealed glass and it requires more force to break through the glass. It is a glass designed to resist injury to property, as opposed to injury to people. It can be used in either buildings or cars. As with most things, there are different degrees of protection offered by different types of glass. Most burglar-resistant glass is actually a glass-plastic sandwich that it harder to break than plain annealed glass. Plano Bath & Glass can install it for you.
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Is there a product that can be put on glass in a shower door or window to create privacy, yet still allow in natural light?
Let's talk about shower doors first. Because they are subjected to heavy water usage, your best bet is to change the glass in the door. There are many beautiful and resilient types of patterned glass that can be used in shower doors (such as obscure or textured) which provide privacy yet let light in. If your budget is not too tight, you might even wish to consider a custom-designed sandblasted or etched door, made to your specifications. The Bath Enclosure Manufacturers Association can help you find a qualified local retailer. Now on to the window. If the window is in the path of the water, then you would be best served to replace the glass in the same manner as the shower door above. BUT if the glass is out of the way of water, you may wish to consider adding window film to the window. The film would provide privacy from outside, yet allow you to see it.
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One piece of glass in my insulating window broke. The glass company is telling me that I need to replace the whole window. Is this true?
Probably. The reason that your window had insulating properties is because there was a SEALED airspace between both pieces of glass. When one of the pieces breaks, not only has that glass been destroyed, but the sealed airspace has been destroyed as well. The whole unit usually is replaced in such cases. Is it possible to reseal the glass in the same frames. The answer is possibly "yes" from a technical standpoint, but 'no' from a practical one. The time and cost involved to retrofit such units would be much more expensive than buying new ones.
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How can I tell if my windows have low-E glass or not?
There are a number of tools and testers available that will check for low-E coatings. A company called Electronic-Design-to-Market makes one. The Micronta brand is also used commonly. These are generally too expensive for the homeowner to buy, but if you call a quality glass shop (link), they will usually be able to test the glass for you. Many window film companies that do residential work also have equipment to check, as film is not generally applied to low-E glass. Sometimes, too the glass will have manufacturers' marking on it that helps tell if Low-E coating is present. There have been a number of scams and consumer rip-offs perpetrated over the past few years, so it pays to be careful on this.
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What is the best way to clean glass?
Well, we hate to say it, but it depends on the type of glass. Mirror, for example is prone to failure when chemicals in cleaning products react with its silver backing along the edges. A very nasty phenomena known as "black edge mirror" can occur. It is very important that mirror not be cleaned with an ammonia product.
Shower doors are also problematic to clean. The Bath Enclosure Manufacturers Association has sponsored a series of studies on the most popular products on the market. Conducted by an independent laboratory, the tests took place on bath enclosures that had been returned to manufacturers with large deposits of soap scum. The cleaners were used on both glass and metal and ranked in the order of cleaning effectiveness and then by gentleness on the metal. As a result of the study BEMA recommends Comet Heavy Duty Bathroom Cleaner in a spray bottle as an effective way to clean your bath enclosure.
The association has not yet tested or evaluated the effectiveness of any of the new cleaners that are sprayed directly on the shower door without washing first.
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Glass in my house just broke, what should I do?
You need to handle glass left in a frame differently than glass that has broken out of the frame and fallen. First, you'll want to check and make sure that no one was injured by the glass. Get medical attention immediately if this was the case. Next, you want to secure the area and isolate the glass that has broken out of the frame and keep people and pets away from the break area. Be especially mindful of infants and toddlers who will crawl by the area hours later.
To clean up the broken glass, pick up the large pieces of glass only when wearing safety gloves. Make note of any special markings or coding on the glass, as this may be helpful in locating a replacement piece. Do not attempt to touch the glass without safety gloves. Put the broken glass in a container and set it aside for disposal by the glass company with whom you work. Do not dispose of broken glass through your normal household disposal methods. Use a high-powered vacuum to vacuum the entire area and dispose of the vacuum bag. Re-vacuum the whole area again a few hours later and dispose of that vacuum bag too.
If the glass is still partially in a frame - say a window pane or door lite - try to secure the area to make sure no one will touch it and that it will not move until fixed. Never go near the glass without safety gloves. Safety goggles are also important to keep glass slivers from entering the eye. If necessary in an emergency situation, you may attempt to put wide pieces of tape, such as duct- or masking-tape across the frame to keep the glass from falling until the glass shop arrives.
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What is Glass?
Glass is one of the most versatile - and most misunderstood - materials used in the world. Glass can be used for everything from eyeglasses to bottles, windows to the 'glassphalt' you find on the road. Many products called "glass" are actually ceramics and have entirely different manufacturing process than the glass we discuss in this article. Glass that is put into buildings or automobiles, in windows or on table tops is usually called flat-, float-, window or plate glass.
The ancient Romans made flat glass by rolling out hot glass on a smooth surface. The resulting glass was neither clear nor even, but it was good enough to use in windows of the day. In fact, glass was quite a luxury at the time and only the nobility could afford it. By 1668, San Gobain had perfected a "broad glass" method of manufacture that involved blowing long glass cylinders, slitting them and unrolling them to form an almost-flat rectangle. This plate glass was then ground and polished on both sides.
By the late 1800s, glass was being made by blowing a very large cylinder and allowing it to cool before it was cut with a diamond. After being reheated in a special oven, it was flattened and affixed to piece of polished glass which preserved its surface. In 1871, a gentleman named William Pilkington invented a machine that allowed larger sheets of glass to be made. It was the first of a number of marvelous glass-related inventions to come from the Pilkington family.
By the early 1900s most glass was manufactured using the sheet glass method--through which a ribbon of glass was drawn from a tank furnace between cooled rollers. It produced a less expensive, albeit imperfect, window.
Manufacturing processes did not change much until 1959 when another Pilkington by the name of Alistair invented the float glass process. It changed glass manufacturing forever. In the float process, a continuous strip of molten glass at approximately 1000 degrees centigrade is poured continuously from the furnace onto a large shallow bath of molten metal, usually tin. The glass floats and cools on the tin and spreads out to form a flat surface. The speed at which the controlling glass ribbon is drawn determines the thickness of the glass. Glass is much less expensive to produce via the float process than any other type of process. Today more than 90 percent of the world's flat glass is made via the float process.
Float glass is very versatile as well. Add a silver backing to it and you have created mirror, heat and then cool the glass very quickly in a special oven and you have made tempered glass. Your windshield is really a "glass sandwich" called laminated glass, made of two pieces of float glass with a plastic interlayer between them. And if you seal two pieces of glass with an airspace between them, you have created insulating glass.
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Is there any way I can take an insulated glass window apart and clean inside?
No, the glass is factory sealed. The glass cannot be cut apart and adequately resealed. Plano Bath & Glass replaces a defective insulated glass unit with a new one. Our replacements have a 10 year warranty.
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What causes my windows to permanently fog up?
Insulated glass consists of two pieces of glass with a sealed dead air space between them. Somehow, the seal has failed. This is usually caused by improper sealing at the factory, i.e., leaving a void in the sealant or an improper compound mix on the sealant itself. If the window becomes cracked, this will also cause the window to fog.
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