Match lime type to exposure and function. Fat lime allows forgiving movement and elegant finishes; modestly hydraulic blends suit wetter zones while still breathing. Sheltercoats can calm patched facades, and sacrificial renders handle salt. Keep test records, note weather, and control curing. A seaside wall we re-rendered with carefully gauged lime survived storms gently, while the neighbor's cement facade cracked and trapped damp, shortening the life of perfectly good brick.
Where structure needs help, hide assistance thoughtfully and avoid irreversible glue wherever possible. Stainless ties, timber scabs, and friction plates can return stiffness while respecting original logic. Use mechanical fixings that can be undone, and document everything. We straightened a sagging lintel with discreet steel angles and careful packing, then concealed them in traditional plaster, allowing inspection in future without compromising historic fabric or leaving chemical residues that age poorly.