Zinc: As regards the material zinc, the double standing seam is seen as a further development of the original hollow seam or the simple standing seam. First mentioned in the relevant literature in 1899, it is the preferred choice over other systems for roof pitches under 25°. The minimum pitch here is 3° (approx 5.2%). The term “double lock standing seam” characterises one of the classic longitudinal joint types used for panels installed next to each other forming a rainproof layer. On international markets it is the 25mm high double standing seam manufactured with pre-profiled panels that has established itself as the market leader.
The Zinc profile is folded and closed manually or mechanically using hand formers or seam closing machines. Special shapes such as convex and concave curves or tapered panels can be produced without any problem. Traditional architecture or modern design will be enhanced by the elegant lines of the double standing seam thanks to its wide range of details.