Reading a building before you change it
An older building is a document, and learning to read it is the cheapest insurance available on a refurbishment. The exercise is not specialist archaeology; it is a systematic look at what is there, ideally before anything is stripped and certainly before anything is covered. Outside, look for straight joints in brickwork where one phase butts another; changes in brick size, colour or bond that mark different periods; a roof line that changes pitch or height; blocked or altered openings, often visible as a difference in the brickwork or a redundant lintel; and differences in the mortar itself, since a cement repair against a lime original is usually obvious once you are looking. Inside, look at floor levels, which frequently step between phases; ceiling heights, which differ between an original room and a later addition; the direction of floor joists, which changes at a structural division; beams and posts that appear to serve nothing, which usually mark a removed wall or an earlier opening; and the plaster itself, since lime and gypsum look and sound different. Then triangulate with documents: historic Ordnance Survey mapping shows footprints at successive dates and settles when an addition appeared; the council’s planning register covers the last several decades; and where the building is listed, the list description records what was understood at the time of listing, though it is a description rather than an exhaustive inventory. What comes out of this is a phase understanding — which parts are original, which are later, which are recent — and that is directly useful. It tells you where intervention is least damaging, because a twentieth-century lean-to can be removed freely where an original wall cannot. It tells you what the appropriate repair specification is for each element. And on a listed building it is the basis of the heritage statement that any consent application will require.
