Many remember well the times when there was practically no choice of adhesives for tiles. The usual cement-sand mortar was used, to which experienced tilers for better adhesion to the surface added PVA or Bustilat glue. True, this did not always help, so the tiles could still fall off over time..
Most modern adhesives for ceramic tiles and porcelain stoneware are still based on the good old sand and cement, but various modifiers have been added to them. It is they that increase adhesion, adhesion of the adhesive to the base and tiles, increase plasticity, water resistance, and extend the service life..
Cement adhesives are traditionally sold in dry form and diluted with water at the work site, they have the widest scope of application and are distinguished by an acceptable price. Other options include ready-made dispersion acrylic adhesives, as well as two-component reactive epoxy compounds, which are also sold ready-made in plastic containers..
The first moment when choosing an adhesive is where exactly it will be used. If outdoors – frost resistance is a very important factor! Therefore, when finishing the facade, for example, with clinker tiles, you should use glue specifically for external work. This is understandable, you say. But adhesives for indoor use are also divided into those intended for the kitchen, bath, hallway …
In general, all adhesive mixtures can be divided into three groups:
- Conventional cement-based adhesive mixture – class C1 according to EN 12004. Adhesion not less than 0.5 MPa. Can be used in dry and damp rooms.
- Class C2 according to EN 12004. Adhesion is not less than 1 MPa, elastic characteristics are increased. More durable adhesives with improved elasticity.
- The third group includes all specialized adhesives, including heat-resistant adhesives for lining stoves and fireplaces, epoxies for laying tiles in the pool, mosaic glue, which has a smaller fraction.
Note that tile adhesive is usually gray in color. But there are white options that are suitable for laying, for example, glass or translucent tiles, marble, which tends to absorb the color of the base, mosaics. In general, the rest of the characteristics of white glue are the same as those of gray compounds..
Experts distinguish two types of glue:
- Thin layer. It is used on almost perfectly flat surfaces, where errors do not exceed 10 millimeters.
- Thick-layer. Accordingly, they are used on surfaces with unevenness exceeding 10 millimeters..
Important!The maximum thickness of the adhesive must be indicated by the manufacturer on the packaging, like all other characteristics.
Of particular note is the fungicidal adhesive for tiles, which has additives designed to prevent the appearance of mold and mildew. An important quality for an adhesive that will be used in wet areas, such as decorating showers and bathrooms.
Let’s talk separately about the glue, which is intended for use on the underfloor heating system. Such glue must be elastic! This composition, after drying, exhibits the properties of low mobility. It is not rubber, but when the tile expands when the warm floor is heated, the glue will not crack, coping well with the linear expansion of the screed. Elastic glue can also be used for tiles that do not absorb moisture, but they are more expensive and are usually used on warm floors or “walking” surfaces that have not yet shrunk, for example.
The most important indicator for tile adhesive is the level of adhesion. We admit that the higher it is, the more expensive the composition will be. Glue with a relatively low tenacity indicator, the first group, can be used on surfaces that tilers call light: concrete, brickwork, aerated concrete wall, on a sand-cement screed. A glue with a higher adhesion level will be required for finishing drywall, wood, glass, metal and plastic surfaces.
In this regard, you should also pay attention to the weight of the tiles. For a relatively small tile on a kitchen apron, you can choose a simple adhesive mixture with an adhesion of 0.5 MPa. But for large tiles used on the wall in the bathroom, or thick terracotta tiles, you should choose a more reliable glue, because they weigh much more.
Important! Average consumption of tile adhesive is 5 kg per square meter. That is, a standard bag of dry mix weighing 25 kg should be enough for laying 5 m2 tiles. However, the consumption will depend both on the skill of the tiler and on the surface itself – the glue will have to be applied in a thicker layer on an uneven surface..
We state: for ordinary tiles of a standard size inside the house, you can use the simplest glue, gray and inelastic, therefore inexpensive. White, flexible, specific adhesives with high adhesion are used in more difficult cases and are much more expensive.
As for specific brands, there are positive reviews about Ceresit CM11 glue, Mapei Keraflex, Knauf, UNIS, LUGATO, IVSIL CLASSIC products. The price of a 25-kg bag can vary from 130 to 1500 rubles.