Is lowE/argon filled glass an option I should consider?
We think so. Most double insulated glass units have an R value of 2.5 center of glass. With the argon filled option, this increases to 4.5 (triple glazed increases to 7.5). The low E reflects 99% of the uv rays, making your house feel warmer in the winter and cooler in the summer. It also hinders fading of your carpet, drapes, and furniture. A good value at 25 to 50 dollars/window in the big picture.
