Window Factors to Consider

Double-pane glass. Double-pane windows are superior to, but more expensive than, single-pane windows. Double-pane windows incorporate two parallel sheets of glass with an insulating dead air space between them. Because of the extra pane—and more importantly, the space between the panes—double-pane windows greatly reduce the amount of heat transferred through the window. Additionally, to make double-pane windows even more efficient, the space between the panes is often sealed and filled with an inert gas, such as argon.

Double-hung windows. Double-hung windows are designed to tilt in to allow easy cleaning from inside the house. This feature is especially nice if a ladder is needed to clean the windows from the outside.