Choosing appropriate windows for a northern residence or commercial building can be a dizzying experience. Functionality, aesthetics, placement, cost, and efficiency are all factors which must be weighed equally.

Moreover, window terminology can be daunting and confusing, but with just a little education, you, too, can become confident when choosing your window supplier.

Window Glazing

The glazing of a window refers to the actual glass in a window. Today, most structures are built with double-glazed windows – meaning that there are two panes of glass in each fame.

Many older buildings and homes still feature single-glazed windows, but buyer beware: windows with a single pane of glass aren’t very energy-friendly. Triple-glazed windows are the best, and as a result, more expensive.


An R-value measures a window’s thermal resistance. In layman’s terms, R-values indicate the amount of heat lost through a window. The higher the R-value of a window, the more efficient it is. Typically, the lowest acceptable value for a residence is R-3.


A U-value – technically known as the overall heat transfer coefficient – measures the level at which windows conduct heat.

For residential windows, if efficiency is a concern, it’s essential to use windows that let out the least amount of heat. Therefore, the lower the U-factor of a window, the better.

For those who live in colder windy climates, equal importance should be placed on the U- and R-values of a window.


Low-emissive, or low-e, windows are one of the latest innovations in the energy-efficiency market. Simply stated, low-e glass traps heat.

Low-e is achieved by placing a thin metallic coating on the appropriate pane of a window. Those who live in more frigid climates should give serious consideration to low-e windowing because indoor radiant heat is reflected inside, thereby lessening the work of your home’s heating system.

Conversely, in the summer, infrared heat from the sun is reflected away – thus making low-e windows a good choice for people in warmer regions as well.

UV Factors

UV rays from solar penetration can wreak havoc on items inside a home or building by causing furniture and carpets to fade in color. That’s why a window with high ultra-violet blockage is recommended, especially for people who live in hotter and sunnier climates.

Casement Windows

If energy efficiency is of the utmost concern, casement windows are the best option. The simple hinge-and-crank design diminishes air seepage, and when wind pushes against the glass, the window seal becomes tighter, further reducing leakage.

Generally speaking, casement windows are hinged on the sides, while windows hinged at the top are known as awning windows and bottom-hinged windows are called hoppers.

Hinged windows must be adequately maintained, as the seal erodes over time. If left unchecked, continued erosion can render the window less efficient.

Other Factors

As taught in elementary school science classes, when there’s a significant difference between indoor and outdoor temperatures, condensation will form on the glass. That’s why you should choose a window appropriate for your climate.

Window placement is another factor to consider when building. If you are looking to increase a structure’s passive solar efficiency, consider the position and location of the building relative to the sun. Windows that face the south let in more heat than north-facing windows.

Also, frames and seals can deteriorate quickly when dealing with extreme temperatures. Choosing windows with warm-air technology and decent spacers is vital.

Lastly, to avoid fines or expensive re-windowing construction, be sure to research and adhere to all local area building codes.

We’d love to work with and advise you of all the window options available today. Please call us, or stop in at either store location and tell us what we can do to help you. We have two convenient store and showroom locations for you.


Consumer How-To Guide by Edwardsville – the Intelligencer

How to Guide by The Lima News

Image credit: Andersen Windows