A considerable amount of heat transfers through windows. If you have single-pane windows, consider doing the following:
- Tighten and weather-strip your old windows and then add storm windows.
- Replace your old single-glazed windows. In colder climates “low-e” coatings on glass can help reduce heat loss through windows.
- In hot climates, consider adding solar screening to west-facing windows that catch a lot of heat late in the day. Solar screening is sold at many home improvement stores.