I have one that I built out of old windows, I used windows that were still in their frames for the most part so that I could open them up to allow for ventilation. However, a hail storm broke out two windows and ruined the roof, but the insurance company came through and now all I have to do is go get the replacement materials and fix it again, I think this time I will replace the broke glass with plex-glass on that side, might help protect it from the hail. What is weird is where the glass was covered with screens you could see where the hail, the size of golf balls, hit but did not break or even crack the glass.