Drone survey in Tiverton

Tiverton is built where the Lowman joins the Exe, with the centre low and residential streets climbing sharply north and west. The consequence for roofs is that a lot of them sit above the general roofline of their surroundings, and a roof that stands proud of its neighbours takes noticeably more wind than one tucked among them.

That shows in the same places every time: ridge, hip, verge and any chimney stack that projects above the ridge line. On a steep site those are also the hardest parts to reach, so they get inspected least and fail most.

The Exe valley here is notably wet, well above the Devon average, which is saying something. Prolonged wetting is the main mechanism of decay, and it favours organic growth on any slope that does not get sun.

There is stone slate on some of the older outlying buildings, which behaves differently from natural slate: heavier, more porous and more dependent on the structure beneath it. Where a stone slate roof has started to sag, a photograph taken from ridge height shows the line of it clearly.

Victorian mill workers' terraces make up a good part of the housing, along with a medieval and Georgian centre and extensive post-war estates. Large modern development sits on the eastern edge.

The terraces have the usual shared arrangements: party walls, common valleys and stacks on boundaries. Those are the situations where a neighbour has to be part of the conversation, and where a photograph of the whole run is more useful than one of a single house.

The Grand Western Canal, the castle and the school buildings are all significant local structures, and the countryside around Knightshayes gives plenty of open ground. Flying here is generally comfortable away from the steepest streets.

The main planning point is the gradient. A take off position on the correct level for the building often means walking somewhere first, which is worth agreeing at the quote stage rather than discovering on the morning.

Tiverton has a number of substantial institutional and historic buildings, from the school to the castle and the properties along the Grand Western Canal, and those carry large complex roofs with long gutter runs and a good deal of lead.

Buildings of that size are difficult to survey conventionally because there is simply a lot of roof, much of it invisible from any point on the ground. An overhead pass produces a complete record in one visit rather than a partial one from several ladder positions.

For domestic EX16 clients the same principle applies at a smaller scale on the Victorian terraces, where a rear elevation with a two storey outrigger has a roof arrangement that nobody has looked at properly since it was built.