Why do commercial roofs leak?
The common sources of commercial roof leaks and the checks that help find the real cause.
The visible drip is rarely the whole story
Water can travel along liners, purlins and insulation before it appears inside. The source may be a failed lap, fixing, flashing, gutter, rooflight or penetration rather than the point directly above the stain.
Common causes
Ageing sealants and fixings are common on profiled metal roofs. On flat roofs, outlets, upstands and poorly repaired details deserve attention. Ponding water, blocked gutters and damaged rooflights can add pressure to an otherwise serviceable system.
What you can check safely
Record when the leak appears, what weather preceded it and whether it relates to a particular bay, outlet or plant area. Avoid walking a roof or disturbing sheets without the right access controls. A survey can then focus on the likely route of the water and separate an urgent repair from a wider condition issue.