DOUBLE PANE WINDOWS COST

Double pane windows are made up of two panes of glass separated by a 0.5" to 0.75" space or gap. The windows are designed to improve insulation and offer better efficiency properties than a single pane window. In fact, single pane windows aren't used very often anymore because of their poor insulating and energy efficiency properties. While most single pane windows offer only an R-1 insulation value, double pane windows typically offer an R-4 insulation value... Double pane windows cost anywhere from $400 to $2500 per window fully installed. The biggest price factors include the frame material, the size of the window and upgrades.