Did you know that the Vinyl Siding Institute does not clarify how vinyl J-channel should be nailed? The nails on siding and corner posts should be nailed “loose” so that they can move freely to avoid buckling with expansion and contraction of the material. I’ve installed siding for over 20 years and I’ve always nailed the J-channel “tight”. I have not once had a call back for any J-channel warping or buckling. The J-channel has enough tight bends in it, with the nails far enough away from the fa