Stone house renovation on the Côte d'Azur

Read the seller's diagnostic file as a list of work. French firms call this kind of project a rénovation maison ancienne, and the file shapes its budget. Our guide to the French property diagnostic report covers every report. Four of them matter most on an old house.

The lead report applies to houses built before 1 January 1949. It tells you where old paint sits on shutters, doors and ironwork, and so where stripping needs care. The asbestos report covers buildings permitted before 1 July 1997. A stone mas (a Provençal farmhouse) can still carry asbestos cement roof sheets, flue pipes or old floor tiles.

The termite report shows the state of the visible timber. Much of the coast sits in the prefectural termite zone, and the mairie (town hall) can tell you whether your commune does. The electrical report, required for installations over 15 years old, lists the risks in the wiring.

None of these reports replaces a builder walking the house with you. Ask a maître d'oeuvre (project manager) or a local contractor to go round before you make an offer, and ask what they would expect to find behind the plaster.

Old stone walls were built to let moisture pass through them. Cement render, cement pointing, plastic paint and some insulation seal the surface, so the water stays inside the wall. The result is damp patches, salt stains and plaster that crumbles from behind. Lime render and lime plaster let the wall breathe.

Ask every contractor the same three questions. Will the render and plaster be lime or cement? How will the damp be dealt with at the source, meaning ground levels outside, drainage and gutters? And what will the inside finish be?

Be wary of a devis (written quote) that prices injection damp-proofing without a diagnosis first. Ask the contractor where the water comes from before they price any treatment.

Insulating an old stone wall from inside is where the wrong material does most harm. Our page on wall insulation explains the options. Before you sign, ask the installer why their product suits stone.

The report in the sale file isn't the survey the contractor needs. In a building permitted before July 1997, an asbestos check comes before the drilling starts, and ordering it is your job as the person ordering the work. The law makes no exception for a private owner. A certified diagnostician does it, and the contractor needs the report before demolition or tile stripping begins. Ask each contractor whether they have seen it.

Old wiring is often decades out of date. The electrical report at sale lists the risks, and a full rewire is normal on this kind of job. Put it in the budget from the start, because the walls will be open anyway. Plan the rewire and the plastering together. Our electrical section explains what to ask an installer.