How Do You Know What Type of Glazing is Right for Windows?

Window GlazeDetermining the type of gazing that is right for windows potentially saves property owners money. It also enhances the satisfaction of the residents with an important home fixture. Learning about the best glazing will increase your wealth, and help you install the right type of window for your particular environmental conditions.

The Purpose of Glazing

Historically, “glazing” represented a way to physically affix glass windows into a frame. In many older homes in the United States, wooden frames represent a popular way to contain glass windows. Builders in the past installed putty to attach the glass to the frame and then glazed over this with an adhesive which hardened over the course of time, according to Popular Mechanics.

Unfortunately, windows do not contain heat well. In many dwellings in colder locations, energy used to heat the home seeps through the fine cracks between window glass and window frames, even when extensive glazing fits the glass snugly into its window pane.

For this reason, many families in colder climates in the past routinely installed special “storm windows” to the exterior of a residence during the winter, according to the Department of Energy. This additional barrier helped keep the premises warmer inside. Today, improved technology allows several options for homeowners who desire highly energy efficient window coverings and glazings.

Glazing Requires Periodic Replacement

Homeowners with traditional glass panes inserted in wood-framed windows need to remember that glazing won’t last forever. It typically breaks down over the course of time (usually requiring replacement every 15 years or so). Additionally, if a window cracks or breaks, residents must re-glaze the window during the course of installing new glass.

“Double” And “Triple” Glazing

Sometimes property owners in very cold climates benefit by installing double-or triple-glazed windows. Essentially, glazing in this context refers to the use of double or even triple panes of glass within the frame. Just as a storm window offers additional protection against heat loss during winter, increasing the number of panes of glass in the frame generally enhances the efficiency of a window all year long.

In very cold, windy climates, using double-or triple-glazed windows holds definite advantages in terms of reduced wintertime energy bills. On the negative side, replacing the glass in these windows often proves difficult. It may in fact become easier to simply replace the entire window if one of the pieces of glass cracks or breaks, rather than to attempt to install new replacement glass.

Double-and triple-glazed windows afford greater convenience in many situations than storm windows, according to the Department of Energy. (In extremely cold environments, of course, residents can use both systems together to keep warm.) If a homeowner installs a double-glazed window, for instance, it may permit the household to dispense with the cumbersome task of applying exterior storm windows as colder weather approaches. Many people appreciate this labor-saving feature.

New High Tech Windows

Today, a wide array of new designs assist property owners in maximizing energy savings. In terms of evaluating the type of glazing on your windows (single, double or triple), it remains vital to match your specific situation with your local conditions to find the type of glazing that is right for windows.

In 1992, the Environmental Protection Agency began an Energy Star label program. Manufacturers seek an independent evaluation of their windows from a testing laboratory to obtain this rating.

Types of Window Performance Measurements

The Energy Star testing evaluates how well single, double and triple glazed windows perform in several different ways. These include:

  • Condensation Resistance
  • U-Factor (Rate of heat transfer)
  • AL (Air Leakage)
  • SHGC (Solar Heat Gain Coefficient)
  • VT (Visible Transmittance)

A low rating in one category might still cause a window to work extremely well in some locations. For instance, in humid climates the condensation resistance factor might matter a lot. Yet in a very cold place, a high U-Factor would likely matter most. Using the Energy Star label system can help you determine whether or not a particular new window will suit your specific needs, based on where you live.

More About Glazing

Modern window technology offers some powerful new tools to enhance the energy efficiency of windows. Today, for instance, it’s not uncommon for window manufacturers to make double- and triple-glazed windows that include fine layers of insulating gas between the panes. They also sometimes apply special coatings to the glass itself designed to reduce glare indoors, or cut energy losses. This “low-e” technology helps reduce energy bills.


For centuries, window glazing mattered. However, the process required periodic repetition. Glazing still holds relevance today, especially within an energy savings context. By using the simple tools described in this article, you’ll readily determine the type of glazing that is right for windows in your home.

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