Drone surveys in Taunton, flown by the surveyor who writes them

Taunton is roughly an hour from Exeter straight up the M5, and it is the Somerset anchor of the coverage. The drive is easy and predictable, which makes it one of the simpler long trips to plan.

It is a substantially bigger town than most on this list, with a Georgian and Victorian centre, extensive Victorian and Edwardian terraces, very large post-war and late twentieth century estates, and continuing major new development on all four sides.

The Vale of Taunton Deane is sheltered by hills on most sides and is drier than Devon, which changes the survey findings noticeably. Less rainfall and less prolonged wetting means less organic growth and slower material decay than the same building would suffer in the Exe or Taw valleys.

What the vale gives instead is fog and frost, because it is low lying and air pools in it. That means freeze and thaw damage to mortar, to the surface of older tiles and to any saturated detail, which is a different failure mechanism from the constant wetting further west. And the surrounding hills, the Quantocks, the Blackdowns and the Brendons, produce localised gusting in storms, so wind damage here tends to be patchy rather than general.

It is worth saying this plainly because a client who has been given a Devon rule of thumb about roof life will find it does not apply here. The buildings age differently.

Clay double roman tile is prominent here in a way it is not everywhere in the coverage. It is a large, single lap tile with a bold profile, it sheds water quickly, and it fails at the fixing and at the batten rather than in the tile. A slipped double roman is conspicuous from the air because the profile makes the gap obvious.

Alongside it there is natural slate, concrete interlocking tile through the estates, and single ply and felt flat roofs on the commercial buildings. The commercial flat roofs are the strongest case for aerial inspection in the town: large decks above occupied premises, invisible from anywhere, with outlets that silt and upstands that lift.

The scale of new development on all four sides means a steady supply of another kind of enquiry too, where the question is about workmanship on a recent build rather than about weathering over decades.

Taunton is big enough that the constraints resemble Exeter's: dense central streets, people on the ground, and airspace to check properly before quoting rather than on the day.

The cricket ground, Vivary Park, the castle and the Tone run through the middle of the town, and all of them are places where the ground under a flight is public. As in every city on this list, the practical answer is usually an early start and a plan made at the desk rather than at the kerb.