Advances in window technology have made it possible for homeowners to increase the number and size of windows without getting clobbered with higher energy bills. Modern windows are either double- or triple-glazed (meaning they have two or three layers of glass rather than one).

New Window Styles

While it usually makes economic sense to replace old, inefficient windows, many folks opt to go a step further and add or enlarge windows. A truly dramatic effect can be achieved by installing semi-circular palladium windows on top of traditional rectangular windows. There are even windows that go around corners to allow for a bright corner view unbroken by framing.

Many people are also installing skylights or roof windows. Early skylights were prone to leaking. Modern, top-of-the-line skylights that are carefully installed by a professional can be expected to remain water-tight for a long, long time. If you are considering skylights for your home, don't skimp. In the long run, you'll be glad you went with the best.

Energy Efficiency

Modern windows rely on a wide array of technologies to achieve a level of energy efficiency as high as five times that of traditional windows. All that technology can also be confusing. Terms like "low-E glass" and "argon gas" don't mean much to the average consumer. Any firm making a presentation to you about windows is likely to use dozens of such terms. Fortunately, there is a simpler way to evaluate different windows.

An organization called the National Fenestration Ratings Council (NFRC) has developed a rating system based on the U-factor. Most windows now carry this rating, so it's becoming easy to make comparisons. You want the lowest U-factor possible. When you talk to different vendors, ask them about their window's U-factor rating. You can also look for the NFRC label. Use the U-factor to compare not only the window's energy efficiency, but its construction quality as well. It simply isn't possible for a manufacturer to achieve a low U-factor rating without using high quality materials and precision manufacturing techniques.

Choosing Installers

Choosing the right firm to install your windows is at least as important as choosing the right window. The window must be installed absolutely level and square in order to perform at the level indicated on its rating label. It's also important that the gaps left around the frame be carefully insulated before the trim is reinstalled.

Another issue to consider is the type of sash. Some windows don't open at all. Because they are useless as an avenue of escape during a fire, these windows should be used sparingly. However, they are by far the most energy efficient, and are ideal for high, out-of-reach locations. The next most efficient closing style is the kind that swing or crank out. When you close these windows, the window sash presses against a pliable piece of weather-stripping. When completely closed, the compressed weather-strip forms a very effective seal.

Window Materials

Least efficient are the traditional sliding sashes. A tight seal makes the window hard to slide, so the seals are left intentionally loose. Over time the seal becomes even looser. While most people focus on energy savings, the savings on maintenance can be even higher. Most replacement windows are made from wood or vinyl. Vinyl windows never have to be painted inside or out. In any painting project, whether interior or exterior, the most expensive part is the windows. Painting all those frames and mullions takes time. With vinyl windows you'll save 30-50 percent off your painting costs. The combination of vinyl windows and vinyl siding can eliminate the need for exterior painting entirely.

Some people prefer the natural look of wood. From an energy standpoint it works as well as vinyl. From a maintenance cost perspective it is inferior to vinyl. If you want the wood look, check out the fake woods first. If they aren't the look you want, by all means go for real wood. For you, the higher maintenance costs may be justified by more pleasing aesthetics.

Financing

Because modern replacement windows can have such a dramatic impact on the appearance of a home both inside and outside, and because they can generate substantial long run savings, they are excellent candidates for financing. You can get the improvement you seek now and offset monthly payments with both energy and maintenance savings. If you use a loan secured by your home, it is likely that you'll realize tax savings as well.

by David Hollies, reprinted courtesy of HomeAdvisor.com