Why the grout is cracking

It happens that after a week after laying your grout (it is possible, expensive and branded) begins to crack and crumble. Why is this happening and how can I avoid it?

It should not be forgotten that grouting is primarily a mixture of cement. A cement requires special conditions for a better understanding. The ambient conditions affect the curing process in all cases, and they can weaken the grout, whereby cracks occur in the grout.

Therefore, first consult the manufacturer's instructions to ensure that the grout has cured properly.

The most common causes of grout, made from Portland cement:

1. Excessive amount of water in the trowel. (Cracks occur due to loss of water during evaporation, which in turn leads to a reduction in the weight of the trowel).

2. In case the tile absorbs too much water from the grout occurs, stop cement hydration process required for normal grouting, troweling and reduced weight.

3. The base for laying the tile is not leveled or is walking with stilts. Such a situation is often encountered wooden houses, where the boards curl or are not tight together. Even if everything is done correctly, most likely an external change in temperature and humidity will help to change the characteristics of the wood and, consequently, the movement at the base.

4. Does not correspond to the type of Grout for tiling installation conditions. If the width of joints greater than 4 mm, the usual grout is not suitable, you must use sand. In any case, in the manufacturer's instructions, the grout width is suitable for grouting.

How to repair the cracked grout made from Portland cement

The cracks in the grout will only increase with time. If it is cracked in the bathroom, you run the risk that the water gets through the cracks and gradually destroys the basics of style and materials that can damage the tile installation and appearance. Therefore, it is best to repair the cracked grout.

If the grout is white

you can gently scrape the grout with a construction knife in the cracked areas and fill in the seams with a new white trowel. This method is not suitable for color grout because the colors can be mixed, superimposed on each other, and no one will guarantee the grout color you will get at the end. Instead of applying a new grout on the crack, which may cause discoloration, it is best to use a construction knife or punch and remove the damaged grout. Keep in mind that grout, made from Portland cement, becomes harder over time and reaches the highest degree of hardness (about 98%) 28 days after laying the tile. Be very careful when replacing the grout to avoid damaging the tile! Change the grout only if necessary.

Mix the slurry, gradually adding the dry ingredients to the liquid,

pouring only about ¾ of the total amount of liquid needed. After mixing all the dry ingredients with the liquid, gradually add the remaining liquid, in small portions, checking the consistency of the grout each time. Just as in the preparation of any other solution, the amount of liquid needed is influenced by many factors, including temperature, humidity, the products used and, in the case of the trowel, it is taken into account, he is colorful. For these reasons, the proportions for the dry and wet components of the mixture will vary. When mixing the grout or other solution, you often have to experiment and make mistakes. If a dry polymer is already added to the grout mix,

To mix the grout, use a rectangular trowel or electric stirrer.

If you use an agitator, it must be immersed in the solution, and then the air will not enter the mixture. Otherwise, air bubbles can weaken the solution. For the same reason, the speed of rotation of the blade must not exceed 300 rpm (air bubbles form at a higher speed). After all components are mixed, and most pieces are broken, let stand for 10 minutes. Meanwhile, the remaining dry pieces should thoroughly wet with the liquid. Then mix the grout again so that there are no more lumps. If you have to prepare several portions of grout, you must make sure that they have the same composition. (When buying more than one grout pack, make sure they all have a serial number).

When mixing new portions, it is necessary not only to observe the same proportions of the components of the mixture, but also to observe the same order in which they are combined and to mix them during the same period of time and at the same time. rotation speed. To ensure that the color of grout facing large areas is constant, when mixing a new portion, add grout from each bag. observe the same order in which they are combined and mix them for the same period of time and at the same speed of rotation. To ensure that the color of grout facing large areas is constant, when mixing a new portion, add grout from each bag. observe the same order in which they are combined and mix them for the same period of time and at the same speed of rotation. To ensure that the color of grout facing large areas is constant, when mixing a new portion, add grout from each bag.