I am not an expert on planning rules and you will need to seek advice for cirumstances particular to your particular property. Nonetheless there are some guidelines you should be aware of – the basic rule is always ask at the local mairie before making any change:
At the time of buying a property you can specify that the purchase is conditional on receiving the appropriate CDU or planning permissions. This needs to be written into the contract (ie not a verbal agreement outside the contract). Your notaire will then be able to help submit the appropriate applications, and the mairie will respond within two months. Secifically, ask for a ‘clause suspensive’ to be inserted to this effect.
- A CDU (Certificat d’urbanisme) shows whether the building or land has, in principle, the right to be developed as habitation(s), and what development is acceptable. The local mairie holds a plan of the commune, which shows which areas are likely to be permitted development.
- A CDU lasts for one year, but can be extended for a further year. Application to extend the life of a CDU must be made at least two months before the original date of expiry.
- Planning permission – permis de construire – is not the same as a CDU. With a CDU you can apply for planning permission. This approves the actual buildings or development that can take place. The planning application will need to be for a building or development that falls within the scope of the original CDU.
- Projects including significant additions, extensions, renovations or change of use will usually need full planning permission. Any project with a floor area greater than 170 square metres requires official plans to be drawn up or approved by a architect qualified to practice in France.
- Almost all changes that affect the appearance of a building, its use or its internal layout require a declaration to your local mairie. They will supply you with the appropriate forms. These include new windows, new roof windows, loft conversions, terraces and many other things
- Extensions to a property that add less than 20 square metres of floor area do not usually require planning permission but again they do need a declaration to your maire.
- External changes are very restricted if your property is within a certain distance of a national monument or castle in France. That dream house in the shadow of a grand castle may be very impressive but replacing the roof tiles may be both difficult and expensive.
One curious situation can arise with the 20 square metre rule – generally buildings of less than this size can be erected with only a declaration to the mairie rather than full planning permission. I have seen a property which consisted of a series of small buildings very close to each other – one the lounge, one the bedroom and so on. And I have received publicity from a ‘Holiday Chalet’ company offering lodges that measured 19.99 square metres and suggesting they were only sold in packs of five. Would you actually get away with five 20 square metre chalets in your garden? I don’t know.