Thinking of going another summer without replacing those old windows? Well, now might actually be the time to act. Not only are efficiencies better than ever, but a $1,500 tax credit is also available for qualified windows installed by the end of 2010.

Steve Linton, director of sustainable technologies at Deltec Homes in Asheville, N.C., notes low-emittance coatings, gas-filled multiple-pane glass and warm-edge spacers among the new window technologies that have advanced in recent years.

Low-E coatings help reduce both the amount of heat entering your home during the day and heat loss at night and during colder seasons. Some manufacturers today offer windows with two low-E coatings, says Scott Young, president of AHT Windows, Clintonville, Wisconsin.

Dual-pane windows are common, but triple-paned windows are attracting more attention from consumers who desire even greater energy efficiency. Likewise, gas-filled windows that feature two layers of gas – preferably krypton – cut decibel noise by half, says Young. Warm-edge spacers and insulated frames improve efficiency along edges, says Linton.

When shopping for replacement windows, make sure the contractor is licensed and a certified renovator with the EPA, says Jared Green with QualiTex, a Canoga Park, Calif., company that provides texture coating for windows and siding. Also, double-check that the windows qualify for the energy-savings tax credit and that the installers use appropriate sealants.