Plasters

Plasters are nothing more than a special type of building mortar. Their properties depend mainly on the nature of the mineral binders, the proportion of ingredients and additives.

There is an opinion that the main function of plaster is to give the walls aesthetic characteristics by changing the color and texture of the surface. In fact, aesthetics is of secondary importance. Correctly selected and laid plaster on the external wall helps to protect the building from various weather conditions, and in the interior it creates a favorable microclimate and allows you to decorate the walls with paint and varnish coatings, wall accessories, ceramic overlays, wallpaper, etc.

Classification of plasters

Currently, the plaster mix market is so rich that every consumer can find a product that would best meet their needs. Leaving aside obvious issues such as choosing the type of mortar in terms of its use outside or inside the building, the products available on the market can be divided into several groups:

• traditional plaster based on mineral binders;
• mineral plaster with specific properties such as water resistance or acid resistance;
• decorative plaster (including colored);
• "noble" plaster based on white cement, various pigments or marble;
• "noble" plaster for "special tasks" - creating special decorative effects, for example, imitating marble finishing.

Construction industry experts have also developed a classification that distinguishes different groups of materials in terms of the methods of direct application of plaster:

• single-layer and thin-layer plaster;
• two-layer plaster consisting of a base and a top layer, usually decorative;
• Three-layer plaster – a combination of traditional and decorative plasters.

For each of these groups, mineral, silicate, acrylic or silicone mixtures can be used. The choice of one or another material largely depends on the needs and tastes of the customer.

Plasters for special tasks

In addition to the main types of building solutions, there are plasters that can perform special tasks. Using lightweight fillers, you can get a lower density of the solution (less than 1.4 mg / cubic meter), which will have a beneficial effect on the thermal conductivity coefficient (0.3 W / (m • K)). Plasters of this type are used in finishing concrete blocks and other similar elements to protect walls from the formation of so-called "cold bridges". Low thermal conductivity of the plaster in this case is achieved by introducing fillers based on expanded clay and perlite (foamed volcanic rock) into the solution. You can also find plasters on the market in which polystyrene granules play the role of filler.

Repair plasters are the only mixtures that can be applied to damp walls. This type of plaster is characterized by high porosity (25-40% by volume) and good vapor permeability. Due to this, moisture evaporates directly inside the plaster layer. Water vapor also does not remain in the plaster, which helps to avoid the appearance of stains typical of old, damp walls.

Plaster that has stood the test of time

Despite the wide range of products available on the market, traditional cement-lime plaster remains one of the most popular types of mixtures. Although the solution does not contain any additives, it is one of the most "tenacious" methods of finishing the facade. The durability of cement-lime plaster is estimated at 60-80 years. In addition, traditional cement-lime plasters are very versatile. They can be used to finish walls inside and outside buildings, used in dry and damp rooms, plastered without the need to apply a primer. Well-applied several layers of traditional plaster protect the walls from erosion. This is achieved by changing the grain size of the plaster in successive layers. The first layer is coarse-grained plaster, then medium-grained, and the process is completed by fine-grained plaster. This arrangement of layers creates a system that literally "pulls" moisture from the walls, which has a positive effect on the durability and quality of the walls.