Panels “lining up” – also a symptom of modern metal roofing. Since they are not intersecting pans and interrupt them for z bar and cap, it’s customary and considered workmanlike to align the pan seams on either side of a hip, or ridge. In seamed work, this is the opposite because folding two intersecting seams into a double lock is very difficult and provides no added value. It is sometimes done by very good folders to “show off” essential how perfect their notching is, but generally it’s frowned upon because again it adds risk, (of folds not completing well) with no added value other than aesthetics. – Kurtis Hord
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Trad Building 