The water absorption rate of a tile refers to the ratio of the weight of the tile itself to the weight of the water after the suction, which reflects the adsorption and penetration ability of the tile. The water absorption rate is closely related to the strength of the tiles, and the water absorption rate is low, which indicates that the compactness of the tile is higher and the strength of the tiles is higher, and vice versa.
Water absorption is a crucial indicator of the quality of a tile, but it is not an absolute indicator. Pursuing a low water absorption rate may also cause problems. Different spaces have different requirements for water absorption, and the way of paving will differ.
Ⅰ. Why the water absorption rate should not be too high?
In the quality sampling of tiles, water absorption is a vital test index, which affects the properties of tile hardness, strength, and wear resistance to a large extent.
Within the standard range, the lower the water absorption rate, the higher the density of tiles, the better the hardness and strength of the product, and the higher the inherent stability.
If the water absorption rate is higher than the national standard, the tile absorbs too much water, and the quality defects such as discoloration, hollowing, falling off and cracking easily occur after the tile is paved, thus causing consumer disputes.
Ⅱ. The lower the water absorption, the better?
Increasingly, consumers are paying attention to the tile water absorption rate, and lots of manufacturers will also use low water absorption as a selling point.
However, this doesn’t mean that the lower the water absorption rate of all tiles, the better. On the contrary, some products and locations need a higher water absorption rate to ensure the paving quality.
Actually, tiles are still coated with cement mortar as the main binder. The way of paving is through the water contained in the cement slurry, which can be absorbed into the tile and solidified, thus forming the grip of the tiles on the wall.
Therefore, if the water absorption rate of the wall tiles is too low, they may miss one another, resulting in insufficient adhesion.
Ⅲ. How much water absorption is acceptable?
According to the latest revised “ceramic tile” (GB/T 4100-2015) standard, ceramic tiles can be divided into:
Porcelain tiles(water absorption E ≤ 0.5%), tantalum tiles (water absorption 0.5% ≤ E ≤ 3%), enamel tiles (water absorption 6% ≤ E ≤ 10%), ceramic tiles (water absorption rate 10% the above).
It can be seen that there is no uniform water absorption standard for tiles. Different products have different standards depending on the applicable space. Generally speaking, the floor tiles are mostly porcelain or enamel.
The national common standard is 3% ≥ floor tiles have a water absorption rate of ≥0.5%. They are qualified; wall tiles are generally fine tantalum tiles, enamel tiles, or ceramic tiles. The national common standards are: 12% ≥ wall tile water absorption ≥ 3% is qualified.
Ⅳ. Which space has severe demands on water absorption?
Bathrooms, showers, kitchens, balconies, etc., have high humidity, are easily becoming dirty, and require frequent cleaning. Commonly, it is recommended to choose tiles with relatively low water absorption.
The toilet has been wet for a long time and is prone to water stains. If the water absorption rate of the tiles is too high, discoloration, mildew, empty drums, etc., may easily occur. Because the kitchen is affected by fumes, the tiles must be resistant to oil and scrub, as well as tiles with low water absorption.
When purchasing, you can check the instructions on the tile packaging to understand the water absorption. A simple water absorption test can also be done by placing water droplets on the back of the tile and observing the diffusion of water. Faster diffusion tiles have higher water absorption, whereas water absorption is lower.
Ⅴ. What should we focus on when applying low water absorption tiles?
Before paving, tiles commonly need to be treated with water soaking. If the water absorption rate is less than 0.5%, it will not affect the water before soaking. For tiles with a low water absorption rate, you should choose to paste more strength materials.
When paving porcelain tiles with low water absorption, tile layers must know in advance the strength of pasting materials to avoid the situation caused by non-tile quality problems.
★ There are 2 methods to determine the water absorption of the ceramic tiles:
🔺 Boiling method
The boiling method is used to classify the tiles and involves drying them out and then boiling them in water for 2 hours, followed by cooling them to normal temperature over four hours.
The mass of the tiles is weighed both before and after the water immersion to determine the percentage of water absorption.
🔺 Vacuum method
The vacuum method evacuates the air from a chamber with the tiles inside and immerses the tiles in water.
Once again, the tiles are weighed before water immersion to determine the apparent porosity, relative density and bulk density.
In general terms, if the tile has low water absorption, its durability and strength are increased. Low water absorption restricts the amount of water that may cause failure by the cyclic salt attack and freeze-thaw.
As long as the method of testing the tile water absorption, you can know more about the tile material and properly choose the tile to pave in different space requirements. The above is about tile water absorption, and I hope it will be helpful to you. If you want to know more, please continue paying attention to us. As a tiles supplier, will provide you with better service and better prices. If you are interested, please contact us at any time. We have professional teams that can answer your questions patiently.