Surfaces lined with ceramic tiles can only be practical and beautiful if quality materials are used and the right installation method is chosen. The durability and reliability of the tiled coating to a greater extent depends on the selected adhesive.
To date, many manufacturers offer a wide range of adhesives for laying ceramic tiles. Although the process of laying tiles, at first glance, is quite simple, but various manufacturers are constantly improving consumer qualities and compositions of adhesive mixtures.
So, on sale there are special adhesive mixtures for solving both specific, narrowly limited tasks, and those that are highly versatile.
The choice always remains with the consumer.
It’s no secret that ceramic tiles can be laid in two ways: with cement mortar and with glue.
The first method, the so-called “former traditional”, is now practically out of use. It consisted of laying tiles on a mortar prepared by hand from cement, lime, sand and water. Using such a mortar, it is good to perform leveling, cover up cracks in the base of the surface, etc. Before laying the tiles on this mortar, it must be moistened so that the ceramic tile does not draw water from the masonry mortar during the laying process. Due to the fact that the masonry mortar is prepared directly on the site, it cannot have an exact dosage of components, each portion of it will differ from the previous one, and, consequently, its physical and technical properties will vary slightly. In this case, the quality of masonry work will mainly depend on the qualifications and experience of the work executor. In any case, a self-prepared solution will be an order of magnitude inferior to industrial tile adhesive.
The second method, the most common at present, is to glue ceramic tiles with a special adhesive. In this case, before laying the tiles, it is necessary to properly prepare the base, level it with leveling masses and prime it with special primer emulsions, since laying is not a small layer, usually 5 – 10 mm. On sale there are also adhesive compositions that are applied with a thickness of up to 20 mm and allow not only to glue tiles, but also to perform minor leveling and elimination of small surface depressions. In such compositions, leveling and adhesive properties are combined. When using such compositions, performers also require certain experience and appropriate qualifications. The main advantage of ready-made adhesives is the constancy of the composition and the ease of its preparation. If you strictly follow the manufacturer’s instructions, then portions of the mortar prepared at different times will have the same properties and have similar characteristics, which especially affects the overall quality of the entire facing surface.
The very rapid development and spread of the technology of mounting on adhesive mixtures and the almost complete rejection of the cement-sand mortar was caused by the emergence of new building and facing materials, innovative construction technologies. Now, more and more, the usual leveling and finishing of the wall using cement-lime plaster is being replaced with fibreboard and gypsum boards. In addition, the requirements for the surface on which tiles are laid have been significantly simplified – it has become possible to perform masonry work on top of old ceramic tiles, on floors with electric or water heating, etc.
Different types of bases require the use of solutions of different types and compositions. When choosing the necessary adhesive, it is necessary to pay attention to the fact that it can provide long-term adhesion of the ceramic tile to the base, as well as meet its certain characteristics (hygroscopicity, deformation, etc.). The classic cement-sand masonry mortar does not meet these requirements.
Over the past few years, the latest trends in construction have influenced both the range of tiles and the improvement of surface cladding methods. Along with the usual standard glazed tiles, many manufacturers now offer unglazed tiles (homogeneous), as well as having different sizes, shapes and thicknesses. Modern tiles have become less hygroscopic, more reliable and durable.
In order to choose the “right” adhesive, it is necessary, first of all, to understand well how its composition affects performance. Depending on the components that make up the adhesive, it is divided into several types:
- cement-based adhesive. This type of glue is the most popular. The dry mixture is simply diluted with the required amount of water indicated on the package. It can have any elasticity. The only drawback is its fast setting in the open air, which requires a certain skill and speed of work when working with it;
- cement-based adhesive with the addition of a plasticizer. The presence of a plasticizer in the adhesive solution makes it more plastic, and also increases the duration of work with it;
- one-component adhesive. These adhesive solutions are produced already in the form of ready-to-use pastes. They do not need to be mixed independently, which eliminates errors in their preparation. A distinctive feature of one-component adhesive is good elasticity, long drying time and ease of work;
— two-component glue (epoxy, polyurethane). Two-component adhesive is sold in the form of several components, which must be mixed before use. During mixing, a chemical reaction occurs, which gives the adhesive properties of this mixture. These adhesives can have different elasticity. Their main advantage is the possibility of using not only as an adhesive, but also in the form of a grout. Two-component adhesives are recommended for intensively used and wet rooms.
In addition to high adhesive power, high-quality glue must have high elasticity. Due to sufficient elasticity, the adhesive is able to easily withstand various deformations and stresses during deformation of the tile or base, which makes it possible to ensure the reliability and durability of the surface when a load occurs without damaging the integrity of the coating. When choosing an adhesive, it must be taken into account that the greater the mobility of the tile and base is required, the greater the degree of plasticity the adhesive must have. If the plasticity of the adhesive is not enough, then cracking of the tile is possible.
Be sure to use highly flexible adhesives when tiling the following surfaces:
- walls built of lightweight concrete (cellular concrete),
- plasterboard walls
- walls built of gypsum blocks and cinder blocks,
- floors with any type of heating,
- walls in panel houses erected from reinforced concrete slabs,
- floors covered with old ceramic tiles or filled with a cement mixture with natural stone chips (terrazzo),
- floors covered with a waterproofing elastic membrane.
In addition, adhesives with high elasticity must be used when tiling various surfaces with glazed tiles, since low elasticity can cause fine capillary cracks to appear on its surface.
Adhesives with maximum elasticity are recommended when tiling in places with the most extreme operating conditions (in swimming pools, on open terraces, etc.), as well as when laying large-size tiles.
Please note that, in general, glue with increased plasticity is not much more expensive than conventional adhesive solutions. When using them, you can be sure that the laid tiles will not crack over time and will have high performance characteristics for a long time.
So, which glue to choose?
Currently, many hardware stores offer a wide range of different adhesive solutions from different (domestic and foreign, well-known and not so) manufacturers. What exactly, what moments, you need to pay attention to? Do not be guided by the price, as it will always be overpriced for products of well-known brands. When choosing an adhesive, first of all, you need to pay attention to the following points: – on what type of base the ceramic tiles will be laid,
- whether this base has irregularities (deviations in the vertical or horizontal plane, swelling, pits, etc.).
If you are dealing with a complex surface, then it is best to select an adhesive that allows you to lay on both thin and thick layers,
- pay attention to the hygroscopicity of the tile, which depends on its type. So, for example, porcelain stoneware (gres tiles), which has low hygroscopicity, is by no means recommended to be placed on an adhesive solution with a high moisture content, since the evaporation of moisture through it in this case will be difficult and the solution will ultimately be bad. bind the tile to the base,
- the size of the tiles to be laid.
Depending on the size of the tile, the consumption of the adhesive mass also depends, so for mounting a large tile, a thick layer of glue is needed, and a small tile is placed on a thinner layer. Some adhesives allow you to lay only small tiles on a thin layer, while others, on the contrary, only large-format and only on a thick layer,
- Place of laying tiles. Depending on the place of laying the tiles (humidity, temperature, etc.), it is necessary to select a specific adhesive with properties characteristic of these operating conditions. So, when laying tiles on the floors in the bathroom over the “warm floors” it is necessary to use a special glue that allows the tiles to shrink or expand depending on the degree of heating of the base,
- installation time. There are cases in which it is necessary to quickly put the premises into operation. In such cases, it is necessary to select an adhesive that can quickly, within a few hours, dry and set.
Currently, many manufacturers offer universal adhesive mixtures that are equally suitable for both natural stone and ceramic tiles, both for mounting on walls and for the field, both for indoor and outdoor work. Along with this, there are also adhesives that are designed exclusively for indoor use on the floor, or that are recommended for laying on a floor equipped with a “warm floor” system. Now the range of adhesive mixtures includes more than a dozen types. Some adhesives are a stand-alone product, while others are part of a whole range of products for preparing and laying substrates. Such complexes may contain various leveling masses, ground solutions, grouts, etc. There are also special adhesive masses with increased plasticity or fluidity, which allow you to perfectly fill the entire inner surface of the tile, preventing the formation of air bubbles under it. A special place in the offered assortment is occupied by quick-setting mixtures, which can withstand operational loads already 3 hours after laying the tiles. Also, there are special adhesive mixtures with very low flow, which are ideal for working on walls, ceilings and when working with mosaics. In addition, some manufacturing companies offer special plasticizer additives for cement-based adhesives, which increase its water resistance, elasticity and setting. They are most often used as a binder with water, and sometimes instead of water. For high-quality performance of facing works using artificial and natural stone, sensitive to efflorescence and pigmentation, adhesive masses were also specially developed.
As you can see, there is currently a wide range of special adhesive mixtures available. Using the principles described in this article, adhering to our advice and carefully reading the recommendations of the manufacturers on the packaging, you will be able to choose the right adhesive for a particular facing tile, perform high-quality facing work and get not only a beautiful, but also a reliable and durable surface.