Ok, I am trying to find the post where someone stated that their roofing panels were actually some type of waste panel that the lumberyards had on their shipped wood loads. I have been building many tractors and have ways to save on framing that I feel I can share. Maybe others have better suggestions for cost savers for us 'penny-pinchers' that result in quality tractors that are frugally built on low-budgets? Here is the first concept/comment to add that I have discovered when building tractors. 1.) Take 2x4 stock and cut with a good table saw. You can cut and make qty 2, 2x2's or 4 1x2's with a few simple passes. Yes, this takes your time- but you will indeed save money if you cut the wood yourself. 2.) Alternative to roofing panels would be wood shingles. I have taken the 2x4x8, with a 12" table saw (10" will not rip the 2x4 on spine in 1-pass) and made 'shakes'. You can get about 6 with a fine cut blade x 8' long. You can be creative in lapping these for the roof, but work well for sides. I am also looking into making 'sandwich' panels with hardware cloth between a rectangle frame (probably 2x4) and then interconnect them with some type of quick release fastener. This would allow easy storage/easy modification (enlarge as the flock gets bigger), decrease the size of the tractor if you are doing small batches etc. The entire tractor would be made of this modular coop panel system. Hopefully, I will have a prototype of this design soon, and will probably post a google sketchup when I get a chance to draw. ANYONE else have some frugal designs to share for these meatie pens?