My 20 ft. x 50 ft. Completely welded all aluminum greenhouse! will never rust and the only bolts are Hilti anchors to the concrete footing.  ​9 ft clearance inside with a 15 ft peak. 

Food production beyond expectations! Super solid structure withstands heavy winds and snow slides off very easily but could handle a heavy snow load no problem! My trusses are only 42" apart so it's built like a tank.  
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