The issue of oil canning, which refers to the visible waviness or distortion in the flat area of metal roof panels, is one that a skilled is trained to minimize. While largely aesthetic and not a structural defect, it can be mitigated through the use of striations or ribbing in the panels, using heavier gauge metal (24-gauge over 26-gauge), and ensuring the panels are installed using... https://kkroofspecialist.com.sg/metal-roof-contractor/