Bruce Saller, ADVANCE CONTRIBUTOR
If you have single-pane windows or dual-pane windows without low-e glass, you can reduce your heating and cooling bills by installing low-e storm windows. (Low-e glass has a coating that reduces heat transfer.) Replacing a single window typically costs $270 to $1377 and generates a lot of trash for the landfill. Adding storm windows is less expensive and can provide similar energy savings.
There are two types of storm windows—exterior and interior. Exterior windows typically cost $60 to $200 per window. Interior windows are slightly less expensive, and you may be able to install them yourself. I found one company selling them for $100 each. Exterior storm windows help protect your regular windows by keeping out the wind and rain.
The energy savings are similar between the two types. The Department of Energy produced a report documenting the estimated energy savings and payback periods from adding storm windows over various types of windows. The results for our area (Climate Zone 4)—by window type, energy savings, and payback period—are:
Single-pane wood: 34 percent energy savings, 8.2 years payback period.
Double-pane wood: 18 percent and 20 years
Double-pane metal/vinyl: 24 percent and 13.5 years
According to the Energy Information Administration, 52 percent of residential energy use is for home heating and air conditioning. Since the average Dominion customer uses 12,000 kilo-watt hours of electricity a year, the annual cost for heating and air conditioning is $1123 (at $.18 per kilo-watt hour).
So, putting storm windows over single-pane wood windows would save you $382 per year; over double-pane wood windows would save you $202 per year; and over double-pane metal windows would save you $258 per year. Your actual savings and payback period will depend on the number and type of windows.
So, rather than replacing your old windows, consider adding storm windows. You’ll save money and keep your old windows out of the landfill.
***
Bruce Saller is a retired systems engineer with degrees in electrical engineering and computer science.
