Rising humidity is a problem that should not be underestimated, as it affects the masonry works from the inside, undermining their integrity. Let’s see what the possible solutions are.
In new buildings the problem of humidity is literally solved at the root, because the buildings are waterproofed and insulated starting from the foundations; however, most of the existing buildings, especially the old ones, are not properly insulated, which is why rising damp is an extremely widespread scourge.
If you think the term plague is exaggerated, know that it is not at all; the rising of water from the bottom, in fact, is completely different from the phenomenon of condensation humidity that is generated following thermal bridges or sudden changes in temperature.
The condensation humidity is deposited on the surfaces of the walls, in fact, and slowly penetrates inside them only if no action is taken immediately; moreover, the stains generated by condensation humidity are mainly due to mold and therefore are of organic origin.
To solve the problem of condensation humidity, in the worst case it is necessary to improve the thermal resistance of the building by applying insulating panels to the walls; in the best of cases, however, it is sufficient to subject the wall to a treatment with suitable products for internal walls humidity , such as sanitizing cycles based on detergents and anti-mold paint .
Rising humidity causes
Even walls in direct contact with the ground, or which are in any case at ground level, are attacked on the surface; in their case, however, the humidity penetrates inside them extremely quickly and completely saturating them to the core.
The causes can be different: the presence of an underground aquifer or the stagnation of rainwater which cannot be completely drained due to the composition of the soil; whatever the reason, the walls in direct contact with the ground are much more exposed to the humidity problem and in a more pernicious way, especially if the waterproofing of the walls is completely missing or badly done.
In masonry works there are hygroscopic salts , which tend to naturally absorb water particles, thus favoring the phenomenon of rising damp , which in some cases can even lead to water infiltration from walls and floors.
With the subsequent seasonal temperature changes then, the water evaporates, but since dissolved salts are present in it, these begin to crystallize inside the masonry, emerging under the plaster layer, causing it to swell first and then split and detach from the wall exposing the efflorescence.
At first glance, these might seem molds but in reality it is saltpetre, easily recognizable by its white color, while the color of molds generally varies from yellow to black through different shades of green, purple and gray.
The further difference between molds and saltpetre lies in the fact that while the former are organic substances, saltpetre is a mineral, and as such inorganic; consequently the sanitizing treatments based on detergent and paint have no effect.
Damage caused by efflorescence
Molds caused by condensation humidity are undoubtedly harmful to human health, as they can cause respiratory problems, allergies and in extreme cases even poisoning and tumors, but to reach this degree of danger they must be neglected to such an extent. that this eventuality is only possible in an abandoned building in an advanced state of decay. In most cases, however, mold is dealt with and eliminated in time, before it can expand further to the point of becoming a health risk.
The efflorescences of saltpetre, on the other hand, do not pose any serious problem from a biological point of view, being inorganic, but since they are formed inside the masonry works and only after having completely saturated them do they begin to emerge, they carry out a disintegrating action on the walls seriously undermining their structural integrity.
Just as the plaster crumbles and detaches under the action of efflorescence, so the concrete and bricks tend to flake, first slowly and then more and more quickly, and if the problem is neglected then the wet and saltpetre-impregnated walls end up with yield under the weight of the healthy ones, leading to the structural collapse of the building or a substantial portion of it.
Moisture from the floor what to do
We reiterated that rising damp mainly affects floors and walls in contact with the ground and those of basement rooms and cellars; furthermore, the phenomenon can be accompanied by possible water infiltrations.
In this case it is not possible to intervene simply by applying waterproofing panels and using anti-mold products; in the case of walls at ground level, an effective remedy against rising damp consists of injections of resin to be made at the base of the same, while for the walls of cellars and basements it is first of all necessary to try to isolate the surfaces of the direct walls contact with the ground by means of suitable products, such as polyurethane foams and waterproofing gels, always through the method of injections through the walls after having drilled them with a drill.
Once injected, the polyurethane foam tends to expand, creating a buffer space between the ground and the wall; the space that is created is then filled with the waterproofing gel, which prevents the humidity contained in the ground from permeating the walls again.
After treatment with injections, it is necessary to wait from 6 to 12 months for the humidity present in the walls to dry completely, after which it will be possible to remove the saltpeter using a special product.
Since these operations are more complex than the sanitizing cycles that are carried out to remove molds, it is advisable to contact a specialized company to have the guarantee that the intervention is performed in a workmanlike manner.