Industrial Roof Condition Survey

Aerial condition survey of an industrial estate roof, flown in overlapping passes to record sheet condition, rooflight degradation and flashing detail without access equipment.

A commercial roof is one of the hardest parts of a building to inspect and one of the most expensive to get wrong. The usual options are a cherry picker, a scaffold, or a person on the roof, and all three cost money, need permits and put someone at height on a surface that may be exactly what you are trying to assess. We surveyed this estate from the air in a single visit. The roof was flown in overlapping passes at a fixed height so the frames line up into a continuous record rather than a set of unrelated photographs. Each sheet run, each valley and each rooflight appears in more than one frame, which is what makes it possible to go back later and check a detail nobody thought to look at on the day. What the survey shows is legible without any interpretation. The rooflight panels have yellowed and stained unevenly across the runs, which is the ordinary ageing pattern for GRP sheets and the thing that determines whether you are looking at a repair or a replacement. Sheet laps, ridge lines, gutter runs and the junction between the pitched roof and the flat roof section are all recorded at a resolution that lets you count fixings. No access equipment was needed, nobody went on the roof, and the tenants below carried on working. The survey took a morning. The images here are stills. The same flight produces the input for an orthomosaic or a measurable 3D model where a client needs areas and quantities rather than a visual record, and that is usually the next question once the condition is understood.