Time changed few weeks ago and all of a sudden it felt like winter. I love winter in Alaska. Warm fires in the fireplace, breathtaking sunrises and sunsets, northern lights and epic star gazing, and of course all of my favorite winter sports.
This past few weeks has been amazing in Homer. Skating on Beluga and Lampert Lakes, the Leonid meteor showers and that Kp7 aurora – it’s been magical. But it is winter and it is getting cold.
My winter bliss is bound to continue with all this snow and today I read an article about Netflix’s new December line up. It looks great! But the prime TV watching couch in my house sits right up against two picture windows it gets cold there.
In Homer, especially in the view homes, windows often dominate the design. But did you know that 50% of energy loss occurs in windows? 50%!! That’s a lot. No wonder my couch is cold.
So when a builder friend suggested I consider windows that absorb the sun’s warmth in winter and block heat loss, he had my attention. I can watch The Crown with a warm fire and draft-free!
What are these magic windows?
They’re called Low-e (or low-emissivity) windows. During the manufacturing process, windowpanes are coated in microscopically thin, virtually invisible, metal or metallic oxide layers. These layers allow visible light and warmth to come into a house and block that heat from escaping.
There are different kinds of Low-e windows for different climates. For example, in Alaska where we try to keep warm for most of the year, there are windows with Low-e coatings, gas fills and proper frames that cause heat gain and remarkably less winter heat loss. But say you live in Florida, you would obviously need the opposite from your windows. You would then look for a different kind Low-e coated window that would use a coating to reduce the amount of heat that enters your home and encourage heat to escape.
The key words to remember are: U-Factor (the rate of heat loss through your window) and Solar Heat Gain Coefficient (the amount of solar heat it transmits). The lower the U-factor, the greater a window’s resistance to heat flow and the better its insulation value. The lower a window’s solar heat gain coefficient (expressed as a number between 0 and 1), the less solar heat it transmits.
I found a great YouTube video explaining solar windows. Check it out.
What’s the best choice for my Alaskan home?
Cold Climate homes need windows with a solar heat gain co-efficient in the range of 0.35 to 0.65 and a U-Factor of .25 or less.
However, you don’t want to install these windows in every room in your house. Instead, the recommendation is to install them on the south side of the house. Put windows with a high solar heat gain coefficient on the east or west facing windows and you’ll risk overheating in the summer as the rising and setting sun beats down on them.
What are the other benefits?
Other than the cost savings from heat loss, these high performance windows have insulating frames that have a warm interior surface so that condensation on interior surfaces is significantly reduced or eliminated. That condensation is something many of us struggle with in winter.
Do you notice the color of your artwork or furniture fading? These coatings can significantly reduce the UV light that causes it.
According to the builder I spoke with, these new windows cost about 30% more than the regular windows available for purchase. Looking at the statistics, they’ll also save you approximately $175 a year from heat loss depending on the size and location of your windows, of course.
Where do I find out more?
For more information, visit the efficient windows collaborative.
To source them locally in Homer, contact Alaska Geo Energy at (907) 399-1799.
Or visit Capitol Northern Windows in Anchorage.