While weeding your garden during this summer’s heat waves, you may have noticed how cracked the soil was. A few days later, your shoes sank in the ground made muddy by torrential rains. This natural phenomenon of shrinkage-swelling of clays (RGA) has been accentuated in recent years by the climate changecausing the multiplication and rapprochement of episodes of very high heat, followed by intense precipitation.
To the point of “weaken thousands of individual houses in France, RGA causing the appearance of cracks which can compromise the solidity of buildings», alerts the Ministry of Ecological Transition, on the occasion of the launch, this month of October, of a experimental help to finance the prevention of RGA in 11 departments which are very exposed to it. Namely Allier, Alpes-de-Haute-Provence, Dordogne, Gers, Indre, Lot-et-Garonne, Meurthe-et-Moselle, Nord, Puy-de-Dôme, Tarn and Tarn-et-Garonne.
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3 million houses affected by the shrinkage-swelling of clays
It must be said that, out of a total of 21 million houses in France, “more than three million are exposed to a high RGA risk”specifies the ministry. The figure even climbs to 10 million taking into account houses moderately exposed to RGA, according to the Qualitel association. A risk which has already materialized for many houses: “Over the last five years, 70% of the cost of compensation Cat Nat (natural disasters) linked to buildings result from the RGA”underlines the Ministry of Ecological Transition. “Particularly vulnerable homes are those built between 1950 and 1990before the entry into force of the latest environmental regulations, in particular RE 2020”which take into account the risk of shrinkage-swelling of clays, specifies Capital Fabio Rinaldi, chairman of the board of construction materials distributor BigMat.
Although this risk is already widespread, and likely to become even more so with the accentuation of climate change, the shrinkage-swelling of clays is mentioned by only 12% of people questioned by Qualitel on their awareness of climate risks for housing, according to the results of a survey published on October 8 by the association. However, a house whose structure is weakened presents a danger for its inhabitants. And impossible to resell to buy another one, no one will want it!
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Possible generalization of public aid in the face of RGA
Hence the State initiative launched this month in the 11 departments most affected by the RGA, in order to allow owner-occupiers of houses to benefit, subject to resource conditions, from a subsidy to finance a diagnosis and preventive work. “The objective is to test and evaluate the most effective solutions, with a view to possible generalization of this device»indicates the Ministry of Ecological Transition. To benefit from it, you must create your account on the platform Simplified Procedures. You can then put together your subsidy application file, attaching the necessary supporting documents, such as your tax notice and your insurance certificates. For carrying out the vulnerability diagnosis of your home, you will be able to benefit, depending on your resources, from assistance representing up to 90% of its cost, within the limit of one spending limit of 2,000 euros.
Once the diagnosis has been carried out, you will submit a second application, to request a grant financing the carrying out of the recommended work. Always depending on your resources, this aid may also reach 90% of the expenses incurred for project management (support by an architect, for example), within the limit of an expenditure ceiling of 2,000 euros, and up to 80% of the cost of the work, capped, at 15,000 euros.
