Budget vs. premium double pane windows

Choosing the right double-pane windows for home improvement projects can be a dizzying process. Not only do you have to think about how the aesthetics of the frame design and material will fit with the rest of your house, but you also want to make smart decisions about glass quality, glazing, coatings and thickness.

Window replacement is often touted as a quick and somewhat simple way to update your home. While part of that might be true, it is also slightly missing the point. After all, windows and doors are the most vulnerable spot in your home's building envelope, which means they can either be an asset or a liability, depending on their quality.

Think of it this way: "Don't skimp on your window budget. A high quality window has so many benefits--lower energy bills, less maintenance, reduced fading of furniture and carpets, improved security, beauty and comfort--it pays to make a good window investment," says Mary McCleod, from the City of Austin Green Building Program.

Premium vs. budget double pane windows

Often, window value is discussed in terms of the cost-effectiveness and value of the frame material. We've heard it before: Fiberglass and wood are usually more expensive but considered better quality, than aluminum or vinyl. Here's a surprise: Perhaps the most important difference between builder-grade windows and premium, double-hung windows is what happens between the glass panes.

Even if they are double-paned, most value-priced windows rely on air as an insulative buffer between the outer glass and the inner glass. This lowers the U-factor of a window, or the measure of heat transference from one side to the other. In terms of energy efficiency, the lower the U-factor, the better.

With premium windows, the void between double-paned glass is generally filled with argon gas, though sometimes manufacturers use krypton. If this sounds vaguely Superman-esque, the choices are made because these gasses are less conductive than air and provide more insulation, which further reduces the U-factor. Using gas can also reduce the profile of the window, or the space between the panes.

Critics sometimes say that buying windows with gas between the panes is a bad idea, because the windows can start leaking argon or krypton within a year of installation. In many cases, these gas-in-glass panes do start to slowly leak; however, these gas leaks are often an extremely small amount, annually. This means gas-filled windows often maintain their insulative value and can hold up well for decades for the investment.

Another thing that affects the initial cost of double-hung windows and long-term savings on heating and cooling bills is the way the glass is coated. Low-E coatings help reduce solar load or aid with passive solar heating.

Combined with gas-filled window panes, low-E technology can really help turn your windows from a liability to an energy-saving asset. With 21st century construction technology, you can even go green with glass. Now that's home improvement.