These windows were all recycled from a local building recycle yard. If you do some research on performance characteristics and don't mind a little variety you can get some quality windows for a fraction of the cost of new ones. (And this was before we had Craig's list!) Now, with a little persistence you can find almost anything you need. The south wall has larger windows while the East and West walls are made up of small windows like these. We still get more heat gain from the East than we anticipated. We hope to correct this in phase 2.