Ok, as you all know I have been burning the Olympic for the past two winters and thank god for that! every summer etc I d oanother insulating project in my older homestead of a house. In the main (open Concept) living are where my stove is, I have 4 windows, double pane but not argon filled etc. This year I am thinking about purchasing those insulated blinds that you can buy for them. I have heard that you lose 20% through windows and doors>? has anyone done this yet? I do know that when I place my hand near the windows on 0 degree days or days that are really windy I can feel a difference.