Drone services in Dartmouth

Dartmouth is built on a slope severe enough that some streets are literally staircases, and that single fact governs everything about maintaining a roof here.

There is no vehicle access to a great many properties, no space for a tower and often no flat ground within reach of the building at all. A scaffold that would be routine elsewhere becomes a project with a plan and a licence.

Buildings also sit above and behind one another, so an upper property's roof frequently discharges towards a lower one, and disputes about where water is coming from are common and difficult to settle from the ground.

Photographs from above resolve that quickly, because the drainage path is visible as a whole rather than inferred from two ends of it.

The timber-framed and jettied merchant houses around Bayards Cove and the Butterwalk are among the best surviving groups in the county, and they carry lead-lined valleys and gutters that are original in concept if not in material.

Lead work fails slowly and expensively. A split in a valley lining does nothing visible for a season and then does a great deal all at once, and the earliest sign is usually inside rather than out.

Listed status means a record of the existing detail is often wanted before any work starts, and photographs taken from above are the only practical way to produce one on these buildings.

Slate hanging is common on the exposed elevations for the same reason it is common elsewhere in the South Hams: driving rain, and walls that need protecting from it.

Timber frame adds a further consideration. Water getting into a jettied frontage does damage that is expensive and slow to discover, so the standard for catching a small failure early is higher here than on a conventional masonry building.

The Dart is busy, the naval college dominates the skyline and the river mouth has its own operational activity, all of which is checked before flying rather than assumed.

Damp is the other constant. The town is sheltered from the open sea by the river mouth but it holds moisture, and shaded slate and lead both stay wet for long periods.

That produces heavy growth and slow decay rather than dramatic storm failures, which means routine condition surveys earn their keep here more than reactive ones do.

Airspace over the river and around the college is checked properly before a price is agreed. It is rarely a blocker, but it does decide the height and the approach a flight can use.

Property, hospitality and marine businesses here all trade on the setting, and the setting only reads properly from height.

The regatta and the river traffic mean summer flights are planned around events and around people on the water rather than simply booked for a fine afternoon.

Photographs of a whole hillside of roofs also settle a recurring local question, which is whose gutter and whose valley an owner is actually responsible for on a slope where four buildings meet at different levels.