Standing seam is a type or profile of metal roofing that is roll formed out of continuous coils of sheet metal. Standing seam roofs are easy to spot because of their distinct raised vertical seams. Each panel should run continuously from the eave at the base of the roof up to the ridge. Properly installed panels should not overlap horizontally as this would compromise watertightness. Larger roofs require the panels to be roll formed on site because they are too long to fit onto a transport trailer. The seams on a standing seam roof are engaged in one of two ways; “Snap Lock” or “Mechanical Lock”.