At the dawn of a new summer, it is difficult not to realize the reality of climate change. Even our homes bear witness to this.
The magazine 60 Million consumers this month devotes a special issue to the damage caused by the drought on the habitat of the French. Amin Meslem, section manager at the magazine, details for franceinfo the details of this survey published in June.
franceinfo: Can you tell us how many houses are already affected? Are we talking about one out of two?
Amine Meslem: Yes, it’s even a little more. Out of a total stock of 20.3 million individual houses, 11.1 million houses are threatened, which is more than 50%. In fact, they are built on clay soils that are susceptible to shifting, due to droughts that harden and shrink when dried out. And conversely, they swell and become malleable when the rains return.
This can cause cracks in the facade, distortion of doors and windows, which can no longer open or close normally, but also a dislocation of paving and partitions, and sometimes even the rupture of buried pipes. And the damage is sometimes considerable, and requires repairs that reach 200,000 or even 300,000 euros.
Really a big blow, and all regions are affected?
Faced with these problems, nearly half of metropolitan France is concerned. There are six departments in particular, which are very impacted, with more than 50% of individual houses, exposed to a high risk. So there is the Gers, with 90% of the houses concerned, the Bouches-du-Rhône, the Lot-et-Garonne and the Alpes-de-Haute-Provence, the Tarn and the Haute-Garonne. In fact, you can see if your home is affected by going to the government’s Geohazards site.
Over the years, it gets drier and drier. As a result, the risk increases everywhere. The problem is that the compensation does not follow. What are the obstacles to, for example, having your municipality recognized in a state of natural disaster? This is a problem that many mayors see.
More than half of municipal requests for natural disaster classification were refused between 2010 and 2020. Because it is not the number of cracked houses or the extent of the damage that determines the classification, but technical criteria.
For example, the Commission, the State services which are therefore responsible for processing these files, these requests from mayors, will first check that the soils are indeed composed of clay. Then, they will look at the weather data, and for the state of natural disaster to be declared, for example, the episode of drought observed must be the most important or the second most important of the last 50 years. Which is no longer very logical, while droughts have nevertheless multiplied in recent years.
And in addition, this criterion is evaluated by comparing a given season. That is to say, for example, if the mayor indicates that the drought occurred during the last weeks of summer, but in fact the Météo France records note that the intensity of the drought was noted at the beginning of the fall, then the application will be rejected.
So we will have to review the way we build our homes, the robustness, think about new materials, for example be more vigilant in the construction areas?
So yes, already for new constructions, the law, there are regulations that have been in force since 2020, which means that people who have a house built on land exposed to a high or medium risk of shrinkage/swelling of clay , must respect certain rules, for example, the foundations of the houses must have a minimum depth of 80 cm to 1m20.
It is also necessary to avoid having a basement, to limit the risk of compaction. Architects also advise using wooden frames, for example, which are less heavy. Here, there are some solutions, but they mainly concern new buildings, for current houses, the solutions are still relatively limited.
Our gardens too, we will have to adapt them. You say, for example, in this special issue, that grass is outdated. Are some trees also threatened today?
Yes, grass is very fragile, it takes up too much water. Fortunately, it is possible to change your lawn, for example by mixing grasses, which are more resistant, such as clover or dandelions, with your seedlings. And as for the trees, it is sometimes necessary to replace species which prove to be unsuitable, for example, it is possible to opt for bushy species, such as dogwoods or junipers, or even fruit trees, which are capable of survive in arid areas, such as the Atlantic pistachio tree.
Our special issue gives many ways to adapt your garden, but also, if ever unfortunately, you are affected by problems that damage the house. We give all the leads to precisely support people in their fight with insurers, all the steps to return to their rights and obtain satisfaction.