Why do properly laid tiles crack?
Release Time:
2021-02-06
Source:
Why do properly laid tiles crack?
Tile cracking typically arises from three main causes: first, quality issues with the tiles themselves; second, problems during the tile installation process; and third, factors related to the substrate and external forces. Below, we will provide a detailed explanation of each of these causes.
I. Tile Issues
Some tiles have a high water absorption rate and insufficient compressive strength, leading to cracking. Additionally, if the tiles are not fully fired during the kiln process, they may crack during transportation, storage, or use. When the quality of the tiles themselves is substandard, the resulting cracks typically form a network pattern—fine, hairline fractures—and such defects tend to occur relatively frequently; in some cases, a single tile may exhibit multiple cracks. This issue is most commonly observed in lower-end products.
II. Paving Issues
1. Use of high-grade cement: For tile installation, ordinary 425-grade Portland cement is typically used, with a cement-to-sand mix ratio of 1:3. However, if the cement grade is too high, the cement mortar will absorb a large amount of water during setting. In this case, excessive water absorption by the tiles can lead to cracking. This usually manifests as multiple cracks in the tiles, with irregular crack patterns.
2. Hollow sounds during tile installation leading to tile cracking: Due to differences in the coefficient of thermal expansion between the hollow and solid areas, as well as between the cement mortar and the tiles, the tiles deform and crack. Typically, the cracked tiles are irregularly distributed, with no discernible pattern in the cracks, which appear linear and vary in length. When tapped, the sound is low, muffled, and dull.
3. If tiles are laid without expansion joints, and the thermal expansion and contraction of the tiles and the substrate are mismatched, thermal cycling can cause the tiles to crack. This typically manifests as chipping at the tile edges and corners, with fine, relatively short cracks on the surface.
4. Cracking of cut and processed tiles: Hidden cracks form during the cutting process, and over time, these cracks propagate due to cement shrinkage and external forces, ultimately leading to tile failure.
III. Grassroots and External Factors
1. Wall deformation and cracking: Due to inherent geological issues, a certain degree of settlement may occur, leading to wall deformation and cracking, as well as tile cracking. This typically manifests as continuous, regular cracks.
2. Breaking walls and other actions that cause wall vibrations, leading to tile cracking.
3. Being too close to heat sources and subject to extreme temperature fluctuations—both excessive cold and excessive heat—can cause thermal expansion and contraction, leading to cracking of the tiles. This phenomenon typically occurs in kitchens, boiler rooms, and similar areas.
