What is the best way to evaluate a window’s energy performance?

There’s tons of different ways. For one, you can check the U-Value. With Anlin, the U-Value of their windows is about 98%. What that means is that 98% of heat will be reflected. That’s a pretty big percentage. I would recommend consulting with your contractor to make sure that your windows have the right amount of U-Value, as well as Low-E and Argon Gas.