The cement mortar on the back of the tile is very uniform, why does the whole piece of tile fall off?

The cement mortar on the back of the tile is very uniform, why does the whole piece of tile fall off?

1. Material issues

Speaking of materials first, whether it is home improvement or tooling, wall tiles are generally divided into two types in terms of texture: glazed tiles and polished tiles. Both have different textures and different construction techniques. As the name implies, glazed tiles are coated with a layer of glaze on the bottom of the blank. The bottom of the blank may be a porcelain body or a ceramic body. The ceramic body needs to be soaked in water. The polished tile body is a porcelain body, and the surface is polished by a machine. It has a high density and absorbs water Rate ≤0.5%, no need to soak in water during construction.

For glazed tiles, either the degree of soaking is inappropriate, or there is dust on the back of the tiles. If the soaking water is too light, the cement slurry cannot be completely immersed into the brick base body, premature water shortage will absorb dry, and the setting will not be firm. Too much water is not enough, and the water layer is easy to form when the brick is saturated and the adhesion is not strong. There is another situation that needs everyone’s attention, that is, the backside dust. This situation generally occurs at the corners, mainly because when workers first soak the tiles and then chamfer, dust will stick to the back of the tiles, and the tiles will easily fall off after condensation. A similar situation occurs in every large project.

Polished tiles. The polished tiles are all porcelain and do not need to be soaked in water, but the cement slurry will not penetrate into the base of the tiles and the adhesion is not enough. Therefore, polished tiles generally require a tile adhesive to increase the adhesion between the tiles and cement mortar.

2. Grassroots issues

There are also several types of attachment bases for wall tiles: aerated block plastered walls, concrete plastered walls, and cement pressure plates plastered walls. Among them, the plastering of aerated blocks and concrete walls requires the traditional construction process shotcrete, but problems will still occur after about a year. (Currently, the surface plastering of concrete, aerated blocks, and cement pressure plates in the construction market is usually used The WHAOS construction interface treatment agent can be directly plastered on the base layer that needs plastering to ensure “0” hollowing, saving time, trouble and money).

3. The ratio of cement sand is wrong

Generally, wall tiles are 1:2, that is, 1 part cement, 2 parts sand, and then paste it after mixing. In many cases, there is no accurate control, 1:4, 1:6 pasted on, very unstable. It seemed to be pasted at the time, but it was easy to fall off after a long time. It was not the quality of the tile paste!

4, the wall foundation is not watered

The wall foundation is not fully moistened before paving, causing the water in the cement mortar and brick body to be sucked away. The mortar does not have enough humidity during the setting time to fully bond the tiles. Before paving, water the base layer with water and control the humidity at 30-70%.

5, the tiles are not enough

Ceramic tiles are ceramic products made from natural clay, which will expand and contract with temperature. The tiles do not leave seams, and the tiles will squeeze off each other. Generally, 1~2mm seams should be left, just like the concrete pavement must be cut to leave seams.

6, the second tap

Many people find that the tiles are not flat after paving, and will be flattened by a second strike, which will cause the mortar that has lost part of its moisture to loosen.