Found a way to stop my new fence from warping in the first season
I built a cedar fence around my backyard in early spring, and by July the boards were already starting to cup and pull away from the rails. I was ready to replace the whole thing. Then a guy at the lumber yard told me to try predrilling the screw holes with a bit one size bigger than the screw shank, but only through the top board, not the rail. I did that on about 20 of the worst boards, and after a full rain cycle, those ones stayed flat while the others kept moving. Has anyone else tried this trick with pressure-treated wood instead of cedar?