Most roof leaks don't start in the middle of the roof. They start at the edges and penetrations. This guide explains why flashing details are the most important finishing step of any commercial roof installation in Edmonton. Learn how parapet walls, roof edges, HVAC curbs, vents, pipe penetrations, drains and scuppers should be sealed. It also covers why walkway pads protect the membrane from service traffic. Getting these details right is what separates a roof that lasts from one that leaks.