MOISTURE

The “health” of walls is seriously jeopardized by moisture. Not only does it cause spots and spalling in wall plaster, but it can also insidiously affect the structure of the materials since its effects are not visible. This phenomenon also places human health in jeopardy since rising damp creates an unhealthy environment which may be the cause of several disorders and health problems.

MAIN CAUSES: RISING DAMP

The wall can be attacked mainly by moisture that flows vertically through the wall structure due to capillary action, the so-called rising damp (i.e. water rises from the soil to the wall by capillarity), by weather-related moisture, caused by penetration of rain water into the wall through the external surface, by moisture due to water infiltration in the case there is ground water or a sudden water presence such as sewage disposal and pipe breaks, and by moisture due to condensation, which originates when the difference in the temperature between the internal environment and the wall is remarkably high.

Almost all the types of moisture mentioned above are sporadic and occasional, except for rising damp, which on the contrary is always present.

We talk about rising damp when the wall draws water from the soil it is in contact with, typically the soil on which the wall is built, but sometimes it also comes from the soil on which the wall rests, the so-called retaining wall. The water rises capillarily after penetrating the wall from the side in this case as well.

EFFECTS: DAMAGE CAUSED BY RISING DAMP

One of the most serious problems the water can cause in walls is surface deterioration when the water freezes. Under these conditions the volume increases, thus exerting enormous pressure on the surface of the pores, making the increasingly deeper surface portions of wall bricks, stone or binders detach. The phenomenon is particularly active when frost-susceptible materials are present.

The same effect, made more evident by dark spots and blooms, is caused by salts, which are always present in the materials constituting the wall and in the water coming from the subsurface. Salts are often highly hygroscopic, i.e. capable of retaining great quantities of water, so their volume increases up to nine times the usual value.

Moisture retained inside walls also produces effects which are less important as far as decay is concerned, but are all-important as far as habitability is concerned. One example of this is resistance to the transmission of heat, which drops to below half with respect to the amount of water contained, leading to well-known economic and health problems (molds, heating costs, etc.).

THE SOLUTION: PROPER AND PERMANENT RESTORATION

The effective restoration of any wall must therefore attain three critical goals:

• prevent water from rising from the soil
• dry the wall, which had been humid for years
• treat salts effectively, preventing their solution into water

The ELO SYSTEM method is the permanent solution to rising damp. Proper restoration is achieved not only by eliminating the water inside the wall (forcing it to go back to the soil following the rise path in the opposite direction), but also by preventing it from rising again (by keeping the system operating) and by neutralizing the salts that are generally present, thus preventing rain or condensed water from re-hydrating them.

After applying the ELO SYSTEM, the wall can be left exposed or it can be plastered with a traditional lime-based plaster that allows the wall to transpire.