Check this before buying French property in a flood zone

Prospective buyers have been warned by an expert to thoroughly check a property's flood risk before proceeding with a sale.

One in four people – some 18 million – now live in an area at risk of flooding, according to the Ministry of Territorial Planning and Ecological Transition.

Around 11 million homes lie within zones at risk of river flooding across 30,700 municipalities. 

And 1.5 million people live in zones at risk of coastal flooding, with nearly 1.3 million homes affected in 1,700 municipalities.

Official flood zone map

Andrew Corpe, of Andrew Corpe Architects in Vaucluse, told The Connexion that one of the main documents that house buyers should check is the plan de prévention des risques d’inondation (PPRI).

The PPRI maps areas exposed to risks, designates a town’s flood zones and provides information on building restrictions.

It may prohibit construction in certain areas, or require building above the highest water levels. It also outlines prevention and protection measures for existing buildings. 

“The PPRI is very important if you are buying a property in France,” said Mr Corpe. 

“Usually the notaire would include information about this in the diagnostics (mandatory technical surveys that the seller must provide to the buyer), but if you are interested in a property it would be best to investigate before the notaire stage.” 

You can request PPRI information at the local mairie or search on georisques.gouv.fr.

“Here, you can find maps and locate the property to see if it is in an area at risk of flooding,” Mr Corpe said.

Flood zone colour codes

Most PPRI maps use colour-coded zones to indicate levels of flood risk, although classifications can vary locally.

Red zones generally indicate those with the highest risk of flooding, dark blue suggests a significant risk, while light blue denotes a moderate risk.

Green zones are generally undeveloped areas that are used as flood plains, while white zones are considered outside the identified flood-risk perimeter. 

“Red is the highest risk where new construction is prohibited and existing properties are subject to very strict restrictions. The advice would be to avoid buying in a red zone,” he said. 

Even if the property is not located in a red zone, it may still be subject to regulations that could affect renovations or other work buyers hope to do to the house.

“The other zones would have restrictions which would also limit extension possibilities on existing buildings and either prohibit new builds or impose design conditions,” Mr Corpe said. 

Research by insurance brokers has also found that it is becoming increasingly difficult to insure homes in areas designated as at risk of flooding. 

Government subsidies are available to help adapt properties to flood risks, with financial aid of up to 80% for modifications such as doorway flood barriers. 

Homeowners can apply through the Fonds Barnier, a scheme established in 1995 to help people exposed to major natural disasters.

Ahead of possible floods, the government recommends homeowners designate a ‘refuge’ area on an upper floor, away from the floodwater.

It also suggests preparing a 72-hour emergency kit in advance, including water, food, copies of ID and medication, and keeping it in a place that is easy to access. 

* Early 2026 saw the longest period of consecutive rainy days since records began in the 1950s, according to state weather agency Météo France.

Rain and storms caused widespread flooding, with residents evacuated in Brittany, and heavy flooding along the River Garonne.