Have you listened to a window sales person or read a brochure? If you weren’t paying attention, you might miss it, but when it comes to the energy you may hear things like up to 10, 20 all the way to 50% being claimed in energy savings for new windows! If only they mentioned the disclaimer, which is that maybe you could save up to 50% of energy lost only through the windows, then they would be telling the whole truth. But that is hardly what you hear!
The fact is unless your windows have a huge hole in them, or you have followed all the recommendations from our previous articles on the energy efficiency pyramid, changing or updating windows is going to have the least energy impact per dollar spent on your home. Even renewable energy at many points can have a better return on your investment than new windows.
Most people do not change windows for energy efficiency. Usually, it is about functionality and aesthetics. We are going to go over first the most cost-effective strategy, improving your existing older windows and then give your tips on purchasing new windows.
Air sealing, insulating, repairing and adding storms to older are the biggest bang for your buck. This stops heat transfer through the window and helps stop air loss as we discussed in part 4 of how to win the biggest loser.
What do the experts say?
Check out this nine-step article on airtight windows from this old house and watch this video animation detailing window air sealing from our partners Blue House Energy in Canada.
After you have completed window weatherization you can, then add Low-E storm windows. Make sure they have the Low e-coating added to help increase the U value and keep cold out during the winter and heat during the summer. Also, make sure to support MI made products and purchase your storms that are made directly in Michigan!
New windows can be pricey and expensive to install in older homes. From better looks to clean them easier or just being able to open them, these are all good reason to update your windows. Energy efficiency is hardly ever one of them though if you are adding more windows to your home, you could bring in more light and reduce lighting bills as well as improve your mental health with natural lighting. If you are updating your windows there some tips to help you get the best ones.
Resistance to heat.
The first thing to look at is U value; this is the inverse of R-value, which we discussed in previous articles. R-value is better when it is higher, but U value is better when it is lower. Windows are measured in U value. The first thing to do is look for energy star certified windows as well as use the energy star website as guidance to select your windows. Energy star in our climate recommends a U value between .3 and .27 and Semco gas utility rebates take effect at $70.00 a window at .3 or less.
Keep the sun out.
If you look at the energy star label, you will see some trade-offs. If you have south or west faced windows that get a lot of summer sunlight, it may be a good idea to consider your solar heat gain coefficient (SHGC). This is a rating from 0 – 1 and it means a lower number the more resistance to sunlight heat that can come in. If you look at the energy star numbers, you will see that there are trade-offs in the SHGC vs. u value. Because you are in a cold weather climate, we typically recommend a higher SHGC to let the needed warm sunlight in, in the winter and then using reflective shades in the summer or building overhangs to keep the light out. You can also grow or plant deciduous trees which will shade your windows in the summer and let sunlight in, in the winter.
Double pane vinyl windows are typically used when windows are updated. Triple pane can save more energy but are very expensive, and they won’t impact much energy usage unless all of your walls have been insulated too. There may be reasons to pick other window materials than vinyl. Vinyl is made from PVC and in the green building world that is becoming to be known as a toxic material that has negative environmental and health impacts. It can harm the people manufacturing it and at the end of it’s life, cannot typically be recycled. Wood windows can be a good choice though they are not as energy efficient. If you do get wood, make sure it is sourced in Canada or the US or comes with a Forest Stewardship Council (FSC) certification, so that to ensure it is not contributing to Amazon deforestation. The other option is fiberglass which is just as energy efficient as vinyl but as the nice look and feel of wood.
Doors that have more glass in them are less energy efficient, but you can get more U value, you can also opt to choose fiberglass core doors instead of metal or wood, which will keep a lot more heat in. Doors, like windows, also need to be air sealed to stay tight.
Having a window, especially a leaky window near sitting or sleeping areas can also create drafts and reduce comfort. Just by simply rearranging furniture away from the window can help you be more comfortable. This can save energy as well because you may be less inclined to turn the heat up more if you do not “feel” cold. This is just about perception though as energy is still being lost regardless of where you move your furniture or how you feel!
How leaky and efficient are my windows?
Have you scheduled your Free Dept of Energy Home Energy Score Assessment yet? If not, be sure to soon while free assessments last. The assessor will help evaluate how leaky and efficient your windows are and help put together a plan for you to improve them in the context of your entire house. You can click here to select your best time or call our assessor David Meeder at 517.256.1839 or firstname.lastname@example.org .
Thanks to SEMCO Energy we have more funding to score more homes and help Holland win. We need you help to spread the word about the challenge and win $50.00 for referring the most friends! Have your neighbors sign up here.