How to Choose the Best Glass for Windows

Looking for the best glass options for windows?  Whether you are looking to let in more natural light or improve your energy efficiency, it’s important to know the best type of glass panel to use in new windows. Without the right glass, rooms can overheat in summer and feel super cold in the winter. This can drive up your heating and cooling costs year-round and make your home a less-than-comfortable place to be.

If you’ve ever stood in front of an inefficient window during the winter (or the height of the summer) and felt the chilly (or hot) air passing directly through the glass, you know the importance of efficient windows. The right glass can help you make your windows work for you—between multi-pane options and energy-efficient coatings, a pro can help you decide on windows that perform at optimum efficiency throughout the year.

Double and Triple Glazing: What Glass Is Best for Windows?

Using single-pane windows is pretty much a thing of the past. Since energy savings is a major concern for most homeowners today, nearly all modern windows are at least double-glazed. This means each window has two panes of glass separated by a thin spacer. That space can also be filled with an insulating gas. These are referred to as Insulated Glass Units (IGUs).

IGUs can also be triple glazed—in other words, a third pane of glass is added to the window unit. Triple- glazed windows are costlier than double-glazed windows. Unless you live in an area with extreme temperatures, you won’t see a significant return on your investment when it comes to energy savings or the sale price of your house. However, talk to your window replacement contractor to see if triple-pane windows are a good choice for you.

The design of the spacer that connects the two or three panes is also important to the overall performance of an IGU. In the past, metal was the primary material used in spacers. The conductivity of metal posed problems, however, and these types of spacers caused condensation and ice crystals.

To reduce the likelihood of trapped moisture between the panes, manufacturers now make spacers out of treated metal or structural foam combined with a desiccant that removes any moisture trapped within the space during the manufacturing process.

What’s the Best Window Glass Filling—Air or Inert Gas?

IGUs were once filled with air. But heat and cold moved through the windows easily, reducing the effect of the double panes. Replacing the air with a less conductive gas reduces heat transfer, improving the performance of the glazing and lowering the unit’s U-factor, or rate of heat transfer.

Most IGUs manufactured today are filled with either argon or krypton gas. Both gasses are nontoxic, nonreactive, clear, and odorless.

Argon gas is more widely used because it’s more cost-effective than krypton. If you opt for double-glazed windows filled with argon gas, the space between the two panes of glass will be approximately half an inch.

Krypton gas takes up less space than argon gas, so it’s particularly useful for preventing triple-pane windows from becoming too deep to fit in a standard window frame. The optimum gap width for krypton gas is three-eighths of an inch, so if triple-glazed windows prove to be the best bet for your climate, your new windows will likely be insulated with krypton gas.

Low-E vs. Tempered Glass

Low-E coatings

A low-emittance (Low-E) coating is a thin layer of metal applied to one side of the glass. Also called low-e glass, the coating is nearly invisible and slows down the rate the heat transfers through the glass pane. The coating goes on the inner face of the glass pane to protect it from the elements and physical damage.

Different types of Low-E coatings have been designed to allow for high, moderate, or low solar heat gain. This innovation helps control the total amount of heat transferred through the panes. It also allows builders to tailor windows to the needs of the house by considering the overall climate and annual weather patterns.

• Higher solar-gain coatings allow more heat from the sun into a home or building, so they’re most commonly used in parts of the country with long, harsh winters.
• Lower solar-gain coatings block approximately 75 percent of the sun’s heat, so they are popular in warm climates.

Tempered Glass

Tempered glass, also called safety glass, is the smartest choice for windows and other glass structures in your home. It is heated and then cooled very quickly during the manufacturing process. This rapid change in temperature makes it about four times stronger than untreated glass.

When tempered glass breaks, it crumbles into small, dull-edged pieces. In comparison, untreated glass will break under comparatively little force and will shatter into dangerous shards.

The International Residential Code dictates where tempered glass must be used in a house and where regular glass is acceptable. But keep in mind that there really aren’t any downsides to using safety glass.

If it is time to upgrade your windows, Best Pick Reports can help. With listings for prequalified companies across the country, finding a window replacement company is as easy as entering your ZIP code. You can hire with confidence knowing that each one of our pros has a history of exceptional service and that they have all required licenses and insurance.

We are so sure you’ll get the best service, we stand behind our recommendations with our exclusive Best Pick Guarantee! In the rare case you are dissatisfied with their series, Best Pick Reports will help make it right or we will pay you up to $2,500 for the inconvenience.