The Deux-Sèvres department is particularly exposed to “wood cancer”.
A prefectural decree of February 2024 provides that in the event of sale of all or part of a building located in demarcated areas, “information on the presence of a risk of dry rot must be provided in the technical diagnosis file”.
Twelve other departments, including Corrèze and Indre, have issued similar decrees.
What is dry rot and why is it so feared?
Read also Housing: these towns in the Oise at war against the invasion of dry rot, a fungus that is devastating to wood
Dry rot is a fungus that feeds on cellulose and lignin, materials present in wood.
The pest therefore destroys everything that contains wood, paper and cardboard.
For it to proliferate, a high level of humidity, darkness, poor ventilation and a moderate temperature are required, specifies a document from Ille-et-Vilaine, also affected.
As dry rot is barely visible at an early stage, clues can still reveal its presence.
If the removal of wood or cardboard materials gives off a strong smell of undergrowth, for example, in the event of damp spots or “cubic rot” in the wood.
The only way to remove doubt is to have a diagnosis established by a professional.
Health dangers
Once established, the fungus spreads throughout the house like cancer.
It can advance by one centimeter per day, hence its nickname “wood cancer” or “housing cancer”.
Its other nicknames are “house leprosy” or “brown rot”.
The pest can, over time, cause a weakening or even collapse of the frame, floor and staircase.
In addition to the risk for the building, breathing dry rot can be dangerous for your health.
Inhaling the mushroom can trigger asthma, allergic rhinitis, bronchitis, cough, breathing difficulties or even sleep disorders.