The defects discussed in this chapter are “mechanical” damage to the lined surface that occurs after a certain period of time, usually too short (usually after a year or two, sometimes after a few months). The defectiveness lies in the durability of the tile, i.e. indicators such as the strength and durability of ceramic tiles should be quite high. Defects are scratches or cuts or even abrasion of the surface, i.e. more or less visible peeling of the surface layer due to wear. In this case, the consequences are both aesthetic (abrasion of tiles, in particular, is noticeable, such a surface loses its original shine, color changes are possible, etc.), and functional, i.e. negative impact on such properties of tiles as impermeability, hygiene, etc. With regard to aesthetic consequences, it must be taken into account, especially in conditions of intensive surface exposure, that the durability and strength of unglazed tiles is generally significantly higher. Since unglazed tiles are uniform in composition and color, in this case the abrasion of the tiles is not so noticeable and does not greatly affect the tiled surface (although it does damage its hygiene). Glazed tiles, on the other hand, have differences between the body of the tile and the glaze in composition and color. That is, peeling off the glaze layer inevitably leads to a change in the tile itself, and consequently to a deterioration in its properties.
Cause
This defect can also be a consequence of a number of reasons. First of all, it is necessary to compare the strength and wear resistance characteristics of the tiles with the Standards and pre-agreed requirements. To do this, you will need samples of the tiles used. If the results of the inspection indicate that the tile does not meet the requirements, it can therefore be assumed that poor quality of the material caused the defects, the tile is “defective”.
However, if the tiles are not defective, then the cause should be sought at the planning and design stage. Most often, it turns out that the tile was incorrectly selected, that is, it does not correspond to the operating conditions of the given surface.
In this regard, it is necessary to highlight the following point, which must be taken into account at the planning and design stage: measuring the abrasion resistance of tiles, glazed and unglazed, in accordance with established standards, allows for a qualitative assessment, but does not provide accurate and documented grounds for making assumptions about durability of tiles. The durability of tiles depends on a number of factors, some of which are quite difficult to characterize, especially those related to certain environmental conditions. Neither the tests nor the concept of abrasion itself reflect such a factor as time, which is fundamental for assessing the durability of the tiles. For this reason, even if the necessary inputs are available at the planning and design stage, there are many uncertainties. For example, for rooms subject to intense exposure, you need to choose glazed tiles with Abrasion Class IV, however, this may not be enough, since different types of tiles with Abrasion Class IV may have different durability indicators under the same conditions.
Another cause of the defect can be excessive, improper care of the facing surface.
Thus, the tile user himself may be responsible for the occurrence of defects if he uses inappropriate methods for cleaning the tiles (for example, using abrasive steel bristle brushes, cleaners and powders with chemically aggressive substances), or if he does not carry out proper regular maintenance of the surface, due to why dirt, waste, etc. accumulate on the tiles.
Prevention
The occurrence of a defect can be avoided if, at the planning and design stage, you carefully select tiles and correctly assess the expected operating conditions. Naturally, when choosing tiles, especially for interior and exterior cladding of public spaces, as well as in industrial areas, you should rely on the highest indicators, including the durability and strength of both unglazed tiles (uniform throughout the entire thickness) and glazed ones, while not taking into account only the quality of the glaze, but also its thickness. It is worth noting that the surface of unglazed tiles, unlike glazed ones, can be polished. Surface polishing helps restore the aesthetic qualities of tiles lost due to abrasion. Private and regular surface care will help prevent dirt from accumulating on the surface, and, therefore, avoid intensive cleaning using aggressive cleaning agents that are unfavorable for ceramic tiles.