How to solve the moisture in walls?

How to solve the moisture in walls. Sergio Sanchez
How to solve the moisture in walls

Before painting a wall, or any other interior and exterior surface of a home, we must ensure that it does not have any moisture that prevents the proper adhesion of the paint.

Some options to eliminate moisture are simple, but in most cases it is necessary to hire specialized professionals or companies to solve the problem.

Basically there are three types of moisture according to their origin. The different treatments to eliminate moisture are applied according to each of them:
  • Moisture by condensation, is carried out by the condensation of water vapor on the different surfaces, including the walls. Excess moisture causes fungal growth and spots that are difficult to remove.
  • Another type occurs because of the absorption and retention of water. Mostly occurs in houses built directly on the natural soil, the so-called capillary moisture. Water rises through the foundations and walls deteriorating not only the paint, but also the structure
  • And another important problem is the “humidity by filtration”. That has its origin in the penetration of water from outside through the walls. Mostly in constructions below ground level, by rains, some source of water from outside, or from breakage of a pipe.


Ventilate the environments

Daily to avoid excess environmental humidity. Bring in sunlight with open windows. In areas without ventilation use extractors to remove moist air and odors. It usually comes from excess steam in areas such as the bathroom or kitchen; so adequate ventilation in these environments is necessary.

Use dehumidifiers in humid areas or climatic zones of abundant natural humidity. A dehumidifier absorbs the water contained in the air preventing it from condensing on the walls.

Install a mechanical ventilation system by insufflation (VMI) which in addition to avoiding condensation on walls and ceilings. Filters the air, evacuates internal gases, and distributes the temperature in the environments. It requires specialized professionals for installation.


Inject into the walls an emulsion based on resins that forms a barrier; so that moisture does not continue to rise through the capillaries of the masonry or the constituent material of the wall. Requires specialized labor.

Apply breathable mortar, which allows the evaporation of the water contained inside the wall towards the exterior surface. It has a greater resistance to moisture than ordinary mortar. In some cases its structure also stops the passage of salts that deteriorate the paint.

Use an electro-osmosis apparatus. Which from a physicochemical process prevents water of the ground from ascending through the capillaries of the walls. There are different types according to need.

How to remove moisture by filtration.

Nothing better than detecting and repairing the source of moisture; such as broken pipes, etc. Which allows rain drops to enter. 

In addition, the deterioration of the structural materials of the house is avoided. Before repair, they should be sufficiently ventilated until there are no signs of contained moisture. That prevents or deteriorates the mortar and the final finish of the paint.

In the event that the origin of the moisture cannot be repaired it can be coated by means of the Coating system. Which through the use of mortars, resins and special additives creates a completely waterproof or water-tight surface or surface.

For more information: How to paint with compressor?