Pathology of dampness. Coated walls in the building sector

Glaser diagrams have enabled us to take a scientific, quantitative approach to natural climatic stresses (heat and water acting separately or together) on components:

• or a single wall (see files [C 7 130] and following);

• or the wall clad with a :

  • D2 decoration: "Pliolite"-type paint,

  • impermeability: class "I4",

  • thermal insulation: interior or exterior.

The aim of the single-wall study was to understand the potential causes :

• in rehabilitation, which are at the origin of the proven pathology, or ;

• in new work, which can give rise to the pathology to come.

The purpose of studying the lined wall is to be able to decide on the solution applied (or planned), the aim of which is to eliminate the cause(s) of this pathology, and thus eliminate its effects.

It enables us to assess the performance of the applied (or planned) solution, but also, and above all, to pinpoint its limitations.

In other words: the hygrothermal study, prior to the implementation of the solution whose aim is to eliminate the cause(s) of the pathology in order to eliminate its effects, must demonstrate, on the one hand, that the problem has been solved, and, on the other hand, that the solution envisaged (or applied) must not be the cause of a new, latent and/or potential pathology.

Here are some recurring problems that can affect simple walls:

• cracks with or without water infiltration ;

• soiling ;

• detachment of exterior or interior plaster ;

• concrete shattering ;

• mould on the inside of the wall.

The mechanisms behind these potential problems are described in [C 7 132] , § 9.2.

Analytical analysis of Glaser diagrams of walls successively coated with different products or systems should enable the builder to assess their curative properties in the face of the potential disorders listed above, while highlighting their performance and limitations.