The two types of standing seam panels are the double lock and the angle lock. These two seam configurations have been used since the nineteenth century for both roofing and wall cladding and provide superior weather resistance in all climates. The double lock is measurably more weather resistant than the angle lock and it is the preferred seam type for most roofing applications; especially for low slope roofing. The angle lock seam is the preferred seam type for façade applications because with its single fold, adjacent panels are allowed to move independently such that thermal movement does not become cumulative and result in excessive movement at façade penetrations which can be difficult to accommodate. This section describes Double Lock Standing Seam applications. It should be reviewed in conjunction with the RHEINZINK Division 7 Binder Chapter (System Overview) on Standing Seam which can be found under the "System Overview and Specifications" tab located under the "Downloads" tab.
