CenterPoint Home Energy Program


New exterior doors often fit and insulate better than older types. If you have older doors in your home, replacing them might be a good investment, resulting in lower heating and cooling costs. If you are building a new home, you should consider buying the most energy-efficient doors possible. When selecting doors for energy efficiency, it oss important to first consider their energy performance ratings in relation to the local climate and the design of your home. Most insulated doors are similar in energy efficiency since the market is so competitive; they're distinguished largely by the quality of their weather-stripping and threshold. Insulating values of R-5 to R-7 (the R-value is the measure of a door's ability to keep heat in or out) are common.

Types of Doors

Wood Doors - An increasing number of manufacturers are offering doors using wood from certified sources. Certification to Forest Stewardship Council (FSC) standards involves third-party evaluation and monitoring of sustainable forestry practices. Although many people choose wood doors for their beauty, insulated steel and fiberglass doors are more energy-efficient.

Steel Doors - One common type of exterior door has a steel skin with a polyurethane foam insulation core. It usually includes a magnetic strip (similar to a refrigerator door magnetic seal) as weatherstripping. If installed correctly and not bent, this type of door needs no further weatherstripping. The R-values of most steel and fiberglass-clad entry doors range from R-5 to R-6.

Fiberglass doors - with highly insulating foam-plastic interiors look good, take finishes well, and hold up better than wood or steel doors (durability being an ecological virtue, too). Glass or 'patio' doors, especially sliding glass doors, lose much more heat than other types of doors because glass is a very poor insulator. Most modern glass doors with metal frames have a thermal break, which is a plastic insulator between inner and outer parts of the frame. Models with several layers of glass, low-emissivity coatings, and/or low-conductivity gases between the glass panes are a good investment, especially in extreme climates. When buying or replacing patio doors, keep in mind that swinging doors offer a much tighter seal than sliding types.

Storm Doors

Adding a storm door can be a good investment if your existing door is old but still in good condition. However, adding a storm door to a newer, insulated door is not generally worth the expense, because you won't save much more energy.

Storm door frames are usually made of aluminum, steel, fiberglass, or wood (painted or not). Wooden storm doors require more maintenance than the other types. Metal-framed storm doors might have foam insulation inside their frames. High-quality storm doors use low-emissivity (low-e) glass or glazing. Never add a glass storm door if the exterior door gets more than a few hours of direct sun each day. The glass will trap heat against the entry door and could damage it.

Interior doors are usually wood, molded hardboard, or hollow core. Since lauan plywood comes from nonsustainably harvested rainforest wood, it should be avoided. Molded hardboard is often made with some recycled content and pressed into shape; some hardboard is made with urea-formaldehyde and should be avoided. While solid wood is beautiful and a natural, minimally processed product, clear stock is becoming harder to get and may come from old-growth forests.


When you buy a door, it will probably be pre-hung. Pre-hung doors usually come with wood or steel frames. You will need to remove an existing doorframe from the rough opening before you install a pre-hung door. The doorframe must be as square as possible, so that the door seals tightly to the jamb and swings properly. Before adding the interior trim, apply expanding foam caulking to seal the new doorframe to the rough opening and threshold. This will help prevent air from getting around the door seals and into the house. Apply carefully, especially if the frame is wood, to avoid having the foam force the frame out of square.

For more information visit: or

Door Suppliers

No items found.