Drone inspection services in Plymouth

Plymouth's centre was rebuilt after the war to a plan, and the commercial blocks that came out of it are largely flat-roofed: asphalt and later single-ply over concrete, parapets all round, hidden outlets, and plant added over decades on top of coverings never designed to carry it. That construction hides its own failures by design, because water that gets past the covering runs sideways inside the build up and appears somewhere unrelated to where it came in.

The parapet is the specific weak point. A coping that has cracked or a joint that has opened lets water into the wall head, and nothing at street level shows it. From above it is obvious in a way it never is from the pavement, which is the main reason this stock reads so differently in an aerial record than in a ground inspection.

Where a block has been re-covered once or twice, the layers themselves become the problem: an old asphalt roof overlaid with single-ply, an upstand that was never raised to suit, and a threshold detail at a rooflight or a hatch that now sits too low. Those are all visible from the air and all invisible from inside.

The city sits open to the Sound and to south-westerly gales coming straight off the Channel. Salt-laden wind carries a long way across the limestone ridges, and the exposed high suburbs at Crownhill and Southway catch the weather badly. For a commercial building that shows up first at the fixings.

Washers perish, the fixing loses its seal, and a sheet starts to lift a fraction in the gusts. Steel gutters corrode at the joints rather than in the middle. Galvanised plant frames go at their feet, where they sit on the covering and stay wet. On the waterfront stock around Cattedown, Sutton Harbour and the Barbican that process runs visibly faster than it does eight miles inland.

None of that is dramatic and none of it needs an emergency. It needs seeing early, and it needs the same asset photographed again next year so somebody can tell the difference between weathering and a trend.

The modern industrial estates east and north of the city are a different problem to the centre. Big spans, composite panel, substantial plant decks, and yards that are busy with articulated vehicles all day. Access on foot means a permit and a slot; access from the air means a cordon in a corner of the yard and an hour.

Around the dockyard and other sensitive sites, airspace and permission questions are real rather than theoretical. Those get checked and resolved before a price is given, and where a location cannot be flown you get told plainly instead of being sold a visit that then does not happen.