Windows and Doors - Factors and Materials

Double-pane glass. Double-pane windows are superior to, but more expensive than, single-pane windows. The double-pane design features two parallel sheets of glass with an insulating dead air space between them. By virtue of this layer of air between the panes, double-pane windows greatly reduce the amount of heat transferred through the glass. 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.

Special coatings. A variety of special coatings can be applied to the glass pane during manufacturing to further reduce the amount of heat transferred through the glass. Low-emissivity glass (or low-E glass, in industry jargon) is designed to reflect infrared heat back in the direction it came from. This means that in the summer it keeps heat out, and during the winter it keeps heat in.

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 would be needed to clean the windows from the outside.  

Exterior doors add a lot of visual appeal to a home, in addition to providing security and insulation. A well-made door, properly installed, can drastically improve energy efficiency in a home, translating to great savings over the life of the house. There are a number of options to consider when choosing exterior doors for the home.

Wood. Wood doors are traditional and have several advantages. They have a lot of visual appeal, are good at suppressing outside noise, and can be trimmed to fit any existing door frame. They are also available in any number of interesting designs. However, wood doors are heavy and tend to sag over time. They are also prone to warping, and they require periodic maintenance in order to maintain their beauty and functionality. If you choose a wood door, make sure that the one you choose is a solid-wood or solid-core door.

Steel. Insulated steel doors are filled with polyurethane foam and can have up to an R-15 rating. They are inexpensive and easy to maintain. They also are superior in providing security for the home. One of the disadvantages is that they cannot be trimmed to fit, and a door frame must be perfectly plumb for the door to be properly installed.