Window shopping: It helps to take pains with advance research

Not too long ago, homeowners thought of windows merely as things to look out of on rainy days. Style was the only concern. But as fuel and utility bills go through the roof, we're quick to learn that cheap, ineffective, single windows cost us money.

Before you go out window shopping to remedy such an expensive problem, it will help to know what's out there. A crash course may help you view what's new!

Windows come with their own alphabet of efficiency terms: R-values, U-values, low-E glass and TJV, rays. A good understanding of these terms will help you select' the right windows for your home.

R-values measure heat resistance. The higher the R-value, the better the insulation.

In general, a single-pane window has an R-1 value, a doubleglazed one is R-2 and a tripleglazed window is R-3. Double and triple refers to the number of panes of glass with sealed air space between them.

U-values measure how well the window conducts energy and, unlike the R-value, includes the performance of the frame and glass. It's actually becoming a better indicator of energy efficiency than the above. Here, the lower the U-value, the better the performance. Most windows rate between 1.05 and 0.23. 11.0.

Low-E refers to a low-emissivity coating on double and triple-glazed windows. It reflects the heat while allowing the light in. If the air between the panes is filled with gas, typically Argon, low-E windows can top R-4. Without the gas, they reach R-3. Low-E coatings cost more, but pay in energy savings.

UV rays refer to sunlight. It can turn a room into a sauna, fade fabrics and make a room too bright to bear.

What do you buy to reflect unwanted light? Low-E films with argon gas are your best solution. Curtains, blinds and shades will help, too.

Manufacturers have produced a window that will reflect or block out the UV rays, but release the sun's radiant heat. This saves your fabric while effectively acting as a solar heater.

How much energy-efficiency do you need? In general, rooms gathering direct sunlight especially those with southern exposures, need stronger insulation - in other words a higher E-value. If you opt for a window with a high solar capacity, you will need shades to prevent overheating in the summer.

Look at the big picture when buying windows. R-values and low-E glass are not the only things that are important. Cheek the frame material, weather stripping and edge construction. Just a tiny crack around the frame of a window is comparable to having a large hole in a wall when it comes to paying heating bills.

A window wall may have appeal until the day you have to wash them. Old-fashioned double-hung windows, are a nightmare to clean on the inside. But manufacturers are working at making cleaning easier.

Casement windows now open 90 degrees. Awning windows open 90 degrees and pivot. Double-hung windows have sashes that tilt. The main types of windows on the market are double-hung, stationary, awning and ones that slide horizontally.

But don't despair if none of these suits your needs. One-of-a-kind windows can easily be custom made.