Monday, October 18, 2010
Updating exterior doors saves money and energy
By Ann Robinson and Annie Schwemmer
Energy efficient updates are a good idea any time of the year. However, as the season changes there is a more measurable and meaningful reason to go green. You can ease the pain of the winter heating bill by making a few simple changes to your outside doors. These simple changes can enhance the energy efficiency of your entire house keeping you warm and saving you money all winter long.
The first culprit is your front door. If you have older exterior doors, air and heat may be leaking out, driving up the energy bill.
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 weather stripping. If installed correctly and if the door is not bent, this type of door needs no further weather stripping.
The R-values of most steel and fiberglass-clad entry doors range from R-5 to R-6 (not including the effects of a window.) For example: A 1 1/2 inch (3.81 cm) thick door without a window offers more than five times the insulating value of a solid wood door of the same size.
Glass or "patio" doors, especially sliding glass doors, lose heat much faster 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 the 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.
Over the long run, the additional cost is paid back many times over in energy savings.
When buying or replacing patio doors, keep in mind that swinging doors offer a much tighter seal than sliding doors.
After years of use, the weather stripping on a sliding door wears down and starts to leak air. You can replace the weather stripping on some glass door models, but for others, you may need to replace the entire unit.
If you are just replacing or adding weather stripping to your old doors, you will want to choose a type of weather stripping that will withstand the friction, weather, temperature changes, and wear and tear associated with its location.
For example, when applied to a door bottom or threshold, weather stripping could drag on carpet or erode as a result of foot traffic. Weather stripping in a window sash must accommodate the sliding movement of the panes — up and down, sideways or out. The weather stripping you choose should seal well when the door or window is closed while allowing it to open freely.
Felt and open-cell foam weather stripping tend to be inexpensive, but they are susceptible to weather and ineffective when it comes to blocking airflow. Vinyl is slightly more expensive than felt and foam, holds up well to traffic and resists moisture.
Metal weather stripping (bronze, copper, stainless steel and aluminum), as you would expect, is the most expensive option but will last for years. Metal weather stripping also adds a nice touch to older homes where vinyl may seem out of place.
If you decide to replace your doors, you may qualify for the energy efficient home improvement tax credits for 2010. Congress has extended energy efficiency tax credits for most homeowners through the end of 2010.
Basically, if you purchase an energy-efficient product or renewable energy system for your home, you may be eligible for a federal tax credit of 30 percent of the cost of the home improvement, up to $1,500. For instance, if you pay $4,000 for a central air conditioning system (excluding installation costs), your credit would be $1,200.
Whether you replace your exterior doors or just seal the drafty old one, you will be on your way to a greener, more comfortable home. Add the kick-back from Uncle Sam and you can't go wrong! As always, we welcome your home architect design questions at firstname.lastname@example.org.