White stain, peeling paint… all signs that saltpeter is attacking your wall. This problem often comes from a room that is too humid and poorly ventilated. It must not be neglected: it threatens the solidity of the building and the health of the occupants. Fortunately, there are effective ways to eliminate it.
In some houses, especially older ones, we sometimes see saltpeter appearing on the walls or ceiling. This is a sign of excess humidity which is gradually eating away at the structure of the building. If left untreated, it can also cause respiratory problems.
What is saltpetre?
Also called stone salt, nitre or even nitrate of potash, saltpeter is born from mineral salts, and more particularly from potassium nitrate, present in groundwater. With a whitish appearance, it happens that a house is subject to it when it is constantly exposed to a high humidity. Thus, it is not uncommon to see traces of saltpeter in cellars. But not only that. An individual house or even a condominium can also be affected. Condensation, infiltration, capillary rise, leaks… there are many factors that can lead to its appearance.
Note that saltpeter does not distinguish between the materials used in the construction of the building. Thus, stone, brick, plaster, mortar and even wood, which it causes to rot, are affected by this scourge.
Although it mainly attacks underground cellars, it is common to see saltpeter appear in the bathroom or kitchen – damp rooms in the house. It settles inside the walls and causes the partitions to crumble. Its very fine crystals take on the appearance of a whitish powder which gradually contaminates each room.
The paint and plaster crumble into powder, the wallpaper becomes stained with large damp marks and peels off, the woodwork darkens and then rots… so many signs which should alert you to the presence of saltpeter in your home.
The risks due to saltpeter
The proliferation of saltpeter in all the rooms of a house weakens the entire infrastructure of the building.
It is also dangerous for health. Saltpeter can in fact cause asthma and other more serious respiratory problems.
For all the reasons mentioned here, it is essential to do what is necessary to treat, stop and eliminate saltpeter from a home.
To do this, it is imperative to determine the cause. Defective pipes, wear of seals in a bathroom, poor ventilation of a room, infiltration through the roof, stagnant water, sloping ground and water pressure on the foundations… call a professional to establish a complete diagnosis of your home.
He will then perform a anti-saltpeter treatment by injecting waterproofing barriers into the walls. Depending on the causes of the saltpeter, he may also recommend drainage of the land in order to stem the problem. Other additional devices can also be installed to dry the air in the house, such as installing a waterproofing membrane at the foundation level.
Finally, it is recommended to equip damp rooms with a Single or double flow VMC, a VMR (distributed mechanical ventilation) or positive ventilation by overpressure.
