This CPD discusses the use of aluminium standing seam roof and wall cladding systems. The original “unhole-y roof” concept was developed in the US in the 1960s, inspired by the efficiency and flexibility of the zips used to fasten clothing. Unperforated sheets of metal were profiled with one small roll standing seam and one large roll standing seam, and secured by placing the sheets over halter clips, with the large roll of one sheet overlapping the small roll of the adjacent sheet. They were then sealed firmly together using a “zipping” machine to close the large roll of the standing seam tightly over the small roll, leaving a secure standing seam. Roll-formed standing seam roofing was first introduced to Europe in 1968, with the opening of a factory in Stuttgart. Today, the concept has evolved and it is possible to achieve complex shapes and geometries, and to use standing seam systems for a range of building roofs and walls.