Windows for passive heating / Discussions

...windows, half of them @45" x 72".  I had a replacement estimate that made me ill, and that was just for vinyl, which you guys don't like.  I live in Colorado, and am just totally confused and discouraged.  When I call to set up appts., a few of the companies have no opinion on windows for a passive solar house.  Any ad...

...windows, or suspended film windows for even higher R values, and windows should have low E coating and preferably be gas-filled. Here is a page that explains what to look for -  Tips for what to look for when choosing high quality windows Another big variable that determines if there will be a net heat gain through sou...