An article in our “make an informed decision” series!
Should I spend the extra cost for foam insulated windows?
It is a rule of commerce that, in general, the next change one makes to a product to improve it has a lower “bang for the buck” than the last change. This makes perfect sense as it would be foolish to not make the most cost effective improvements first!
After over a quarter century of adding products such as low E glass, gas fillings in the glass sealed unit and better, more energy efficient styles and designs, in order to offer you the best possible products, the industry has turned to additional options such as triple glazing and foam filling. We’ll talk about triple glazing elsewhere, but now let’s review the growing availability of foam insulation in window frames and sashes.
There are two main methods of adding foam. One is to use a liquid that expands inside the window cavity to fill it and the other is to use a pre-formed material inserted into the cavity. Companies, using either method, will insert their foam into specific cavities designed to maximize benefit, without interfering with critical functions such as drainage or reinforcement.
Now for the fun part! Companies that are actively promoting foam tend to use a bit of misdirection. Do you know that foam insulation in a frame may improve the frame’s insulating value by 15 to 20%? Wow!!! That sounds great… sign me up! Not so fast…. Most of the heat loss in a window is through the glass, not the framing materials. That 20% improvement may only translate to an approximately 2% improvement in your window`s performance overall. Not quite so impressive!
Still, it does offer an improvement at a cost. Depending on your budget, after you have added the more cost effective ways to improve your windows performance, this is an option you can always consider.