Top Double Pane Window Brands

Double pane windows feature two panes of glass separated by a layer of air or inert gas. The space acts as a barrier to heat and radiation. Since air can condense when the temperature changes, inert glass in that space will prevent condensation and insulate. The inner surfaces can also be coated with special materials to filter out harmful rays. Where the coating is applied depends on your prevailing climate, hot/cold-north/south, etc. These top double pane windows brands provide a starting set of double pane windows:

• Alside Ultramaxx comes with a U Factor of .3 and a solid intercept spacer. Tested in adverse conditions with a very good rating and positive customer reviews. Price: approximately $395
• Certainteed Bryn Mawr II uses the proprietary Thermaflect® Low-E process to keep its double pane windows up to Energy Star® standards. It also features warm-edge technology and honeycombed areas in the sashes to minimize heat conduction. Price: $250
• American Craftsman 9500 LoE2 argon filled dual pane glass, warm edge Intercept® spacer, fusion welded frame and sash. Several glass options are available with U Factor of .48 (clear glass) to .3 (LeE3 argon fill). Price: $220.

The above data reflects Consumer Reports testing. All represented are vinyl double-hung windows. In wood configurations, Marvin, Andersen, Pella, Jeld-Wen were considered, but vinyl presents the more economical choice.