Leadwork in Plymouth

Why lead matters so much on Plymouth roofs

The pre-war stock that survived the Blitz — Devonport, the Hoe, the Barbican, Stonehouse, and the Victorian and Edwardian terraces out through Stoke, Ford, Mutley, Mannamead, Peverell and Lipson — is full of the details that lead was invented for. Chimney stacks rising through a pitch. Valleys between two slopes. Parapet gutters hidden behind a front wall. Abutments where a lower roof meets a taller neighbour.

Conservation area appraisals for Devonport describe hipped slate roofs on buildings such as Admiralty House and Hamoaze House; the Barbican appraisal records slate roofs on the Corporation flats in Looe Street and How Street. Roofs like these live or die on their leadwork.

The failure we are called to most

Mortar and sealant used as a substitute for lead. It is quick, it looks tidy for a year or two, and then it cracks — because the mortar cannot move and the roof can. Once water is behind a stack it travels, and the damage is usually well away from the entry point by the time anyone sees it.

• Chimney flashings and soakers cut and dressed to the slate course, not smeared over it.
• Valley linings with correctly sized bays and proper laps, so thermal movement has somewhere to go.
• Parapet and box gutters, including the hidden ones on Georgian and reconstruction-era frontages.
• Abutment and step flashings chased and wedged into the joint properly.
• Dormer cheeks and tops on the terraces where dormers already exist.

Listed buildings and conservation areas

Plymouth has more than 800 list entries and 15 conservation areas. On a listed building, replacing lead like for like is normally the expectation, and changes may need consent. We would rather have that conversation before starting than halfway through. Related: roof repairs, re-roofing.