I am getting ready to put up my greenhouse, a hoop type, gothic style that i bought at auction. Basically, i have no instructions so i'll put it up the way it was, but i wonder if i should do more. It had no cross braces (it's 26' wide) and has 5 purlins. I have seen other's set with braces set diagonally to the frame, or using wires. Do you think they are needed? Any other tips to putting this thing up?