The Truth About Energy Savings and Windows – Part 1: Claims versus RealityJanuary 05, 2015
If you’re looking for an energy efficient window, there’s a good chance that you’ve come across some products that offer “very good” energy efficiency. These window products can cut down your home’s electric bill by up to 50% or more. Many homeowners buy these kinds of windows, install it on their home, and find themselves a few months later that they’re barely saving anything near 50% every month. What went wrong?
The fine print
The problem here can be traced back to the window’s original labeling. The fact that the label says your new window can cut down the electric bill by up to 50%, means your total monthly savings can be anywhere from 0% to 50% of your usual bill. Unfortunately, you’ll most likely be saving less than 10% of your regular monthly bill!
Why would the seller exaggerate their product’s claims? It’s because local laws and regulations prevent businesses from making false advertisements. Using “up to” is considered acceptable, and you can bet that many window companies are taking advantage of that loophole to make their windows look as good as they come.
The real deal
Of course, the window seller can actually claim that the windows are proven to cut down electric bill costs, but those optimal performance figures are almost exclusively seen in tests with carefully controlled factors. So what are the actual figures?
According to estimates, actual savings can vary depending on different times of the year. For example, energy efficient windows can help save around 20-25% in energy costs during summer, but during winter, the total savings are reduced down to 10-15%. This is comparing windows with energy efficient features with a standard clear glass window with a nonmetal frame.
Why do low-E windows have a reduced efficiency during cold seasons? It’s largely because of the fact that some energy features such as low-E glazing is focused on reducing total heat absorbed, which is great during summer, but not so much during winter.
The energy efficiency of windows may be exaggerated at times. However, does that mean they are not worth it? The next part of this blog series will tell you otherwise! Stay tuned for Part 2, coming soon.