Drone roof survey in Tiverton

Tiverton is built where the Lowman joins the Exe, and the residential streets climb hard north and west out of the town centre. On sloping ground a roof is not exposed according to its own height but according to where it sits relative to everything around it, and a house halfway up a Tiverton hillside can be standing clear above the roofline of the whole street below it.

Those roofs take wind loading that the same building would never see on the flat, particularly on the ridge and at the gable verge. It is the reason ridge tiles come off some streets in this town most winters and never come off others a few hundred metres away.

It also affects access. A scaffold on a sloping plot needs levelling, additional bracing and often a base that has to be built up on one side, which is a meaningful chunk of cost before any inspection has happened.

The Exe valley here is consistently wetter than the Devon average, and roofs in Tiverton spend a lot of the year wet. Water is the mechanism behind nearly every roof failure that is not caused by wind: it drives the freeze and thaw that opens mortar, it feeds the moss that blocks valleys, and it corrodes the fixings that hold everything on.

North-facing slopes are the ones to look at first. They receive little direct sun through the winter and can stay damp continuously from October to March, which is why the same roof will be sound on the south slope and covered in growth on the north.

The canal side properties along the Grand Western have the additional issue of constant damp proximity, which affects the lower courses of the roof and the wall head beneath them.

The town has three distinct kinds of building and all three come up regularly. The Victorian terraces built for the mill workforce are tight, slate, with shared party walls and valleys between rear projections, and they behave like Exeter's terraced stock.

The Georgian and older buildings around Gold Street and Angel Hill are more complicated, with multi-level roofs, numerous valleys and abutments where later additions meet earlier ones, and stone slate on some of the oldest.

The post-war and modern estates at Post Hill and towards the eastern extension are concrete tile on standard pitches, where the issue is bedding, fixing specification and, on the more exposed plots, whether the ridge was mechanically fixed at all.

Tiverton Castle and the grounds at Knightshayes sit at opposite ends of the town from the mill terraces, and both carry the kind of ornamental and outbuilding roofing that a straightforward survey checklist does not anticipate: turret roofs, lean-to glasshouses, coach house slate laid to old patterns. None of it behaves like a standard domestic roof, and none of it should be assessed by the same assumptions.