An important step in preparing the walls for further finishing is plastering the walls. It is used in major or cosmetic repairs to align the walls or as a finishing coating. Plaster facades creates a layer that protects them from the negative effects of rain, wind, ultraviolet. In addition, the coating provides additional thermal insulation effect. This reduces energy consumption for air conditioning in summer and heating in winter. For this purpose, use different types of plaster, different composition, characteristics, features of application.
Classification of plasters carry out on several indicators. By location, they are facade and interior. The first is used to work on the street, and the second – in the middle of the building. The facade is more exposed to mechanical stress, so the plaster should create a strong, stable, durable coating. To the materials inside the room there are more requirements for decorative properties. Modern mixtures for plastering can often be used both inside and outside the house. The choice of material depends on the type of base, the desired effect. Different types of plaster have common advantages:
- increase sound insulation;
- allow you to insulate the room;
- improve fire-fighting condition;
- protect walls from moisture, temperature changes.
Plastering of walls is a time-consuming process that requires high qualification of the master. For functional characteristics of plaster are common, thermal insulation, acoustic, waterproofing, special, decorative. Let's see what features are inherent in each species, and how they affect the use of the material.
CONVENTIONAL PLASTER
The main objective of its use is the alignment of the walls in preparation for further finishing (painting, laying tiles, panels, wallpapering). The result is a monolithic layer, resistant to mechanical stress and the influence of weather factors. The composition of the mixture is isolated such types of plaster:
- Lime. It is used for roughing the walls inside the building. It can not be used on gypsum surfaces, in areas with high humidity.
- Cement-lime. Their basis is cement, lime mixed with sand and synthetic additives. This view is used inside and outside the house. Cement provides the solution with strength, resistance to moisture, and lime – plasticity.
- Lime-gypsum. It can be applied to the walls of wood, stone, plaster, but not on concrete surfaces. The advantage of the coating is its resistance to moisture.
- Cement-sand. This is a traditional type, proven strength and reliability. Its disadvantage is the possible dampening of the surface, which contributes to the appearance of mold.
The advantages of conventional plaster are durability, versatility, efficiency. The disadvantages include the complexity of the execution, the need to withstand the time for drying each layer.
INSULATING PLASTER
It can be applied inside the house or on the outside of the walls. Its peculiarity is the presence of a binder component (cement, lime or gypsum) and various fillers in the mixture. Due to the porous structure of the fillers increase the thermal insulation ability of the material. As fillers used:
- Foam glass. Obtained from foamed quartz sand. Under the influence of high temperatures, a porous material is formed, with low water absorption, non-combustible. Glass balls inside the foam glass do not shrink.
- Vermiculite. It is formed from swollen mica at high temperatures. The filler is able to withstand large temperature changes. Its disadvantage is the high hygroscopicity, which helps to reduce the application of the finish coating.
- Perlite. During the firing of volcanic glass, air bubbles are formed in it. They give the material heat and sound insulation properties. The lack of perlite absorbs water much. It must be covered with a protective layer.
- Foam polystyrene. It has excellent thermal insulation properties, but is a combustible material. This limits its use.
Sawdust. Cheap and quite effective filler that can be prepared independently. It is used for interior work.
Warm plaster is used as an additional thermal insulation layer. Apply it can be a layer of up to 50 mm, otherwise under its own weight it will slide off the wall. If it is necessary to achieve good thermal insulation, it is possible to apply plaster from inside and outside of walls with a total thickness of up to 100 mm.
The advantages of warm plaster are its fire (except Styrofoam) and environmental safety, practicality and functionality. It fits perfectly on any base, creating a single structure with it. The technology of applying the solution is practically no different from plastering with a conventional mixture.
ACOUSTIC PLASTER
To reduce the influence of external factors on the atmosphere of the house, use special formulations. They are indispensable in the complex configuration of the walls, the inability to use other methods of sound insulation. It is often used for decoration of industrial buildings, concert halls. In an apartment or house, it will make your stay more comfortable, especially when decorating rooms with hard materials (marble, tiles).
A feature of the acoustic mixture is the presence of sound-absorbing additives. These include expanded clay, pumice, vermiculite, perlite, slag. It can be applied to any pre-primed surface in several layers. The final layer is leveled poluterkom. Hardening of the solution should take place with warm dry air. The coating should not be painted, so as not to deteriorate its sound insulation properties. Therefore, it is tightened with a cloth or covered with grids. The advantages of this type are the lack of joints, the ability to pick up any color, damage is repairable.
WATERPROOFING PLASTER
For finishing of rooms with high humidity ‑ basements, bathrooms, balconies ‑ use plaster compositions with waterproofing properties. The mixture consists of mineral binder (cement), filler, mineral and polymer additives. It is closed with water, mix thoroughly.
The surface of the walls before applying should be cleaned of dust, debris, grease. Apply the mixture should be at positive temperatures. During the hardening process, the solution must not be frozen, dried or moistened. It should be protected from damage.
SPECIAL MIXTURE
Often, for wall decoration is necessary to use a mixture with unusual properties. Such materials include x-ray protective plaster. Its main component is barite concentrate. Such a solution is much cheaper than a lead shield, which is a reliable protection against electromagnetic radiation. The plaster is applied to a layer up to 50 mm. For best protection, use of barium plate. Application of barite plaster is carried out at a time, as the surface should not have joints. The air temperature should not fall below 15 degrees.
Another variety ‑ acid-resistant plaster. It is used in rooms exposed to aggressive chemicals. The basis of the mixture is a liquid potassium glass with the addition of stone flour and quartzite. To protect the coating from damage, use skim
A LAYER OF CEMENT-SAND MORTAR, OVERWRITING IT WITH CEMENT MILK (DRY TOPPING).
DECORATIVE PLASTER
To make the walls not only functional, but also beautiful, use decorative plaster. The coating can be structural, textured and Venetian. The first two can be used outside and inside, and the Venetian – only inside the building. There are several types of mixtures that differ in the binding component:
- Acrylic. Due to the acrylic resin, it is highly ductile. Due to the pigments it gives the desired color. Plaster has high strength, creates a smooth coating. Its disadvantage is low vapor permeability, exposure to ultraviolet light.
- Mineral. The main component in it is cement. It is relatively inexpensive, the strength of the coating increases over time. Does not fade in the sun, but does not tolerate mechanical stress.
- Silicone. Due to the synthetic resin plaster has acquired resistance to moisture, good plasticity. It is easy to apply, varied in color.
- Silicate. The binding component of the solution-liquid glass-gives it strength, makes it resistant to moisture. Plaster is suitable for all surfaces. It is fireproof, has a long service life - up to 50 years.
The basis of mixtures of structural plaster are silicates or acrylic with the addition of granules of different sizes. Due to this, the coating acquires volume. With the help of different application techniques create different decorative elements on the surface. Used for facades and interior works.
The peculiarity of textured plaster is its high plasticity, which allows to form any pattern on the coating, to create an imitation of natural materials. To do this, use a variety of rollers, spatulas, sponges. Added to the mixture of fiber, small stones, stone dust. Due to this, the coating hides minor flaws of the walls, does not require their prior alignment.
Venetian plaster has a unique decorative effect. It perfectly imitates the marble surface, conveying its inherent brilliance and depth. This is achieved due to the unique composition, including marble flour and astringent component (acrylic or lime). The solution is applied in a thin layer in several stages. This type is the most expensive and time-consuming, but for decorative properties it is difficult to find a finish that would look so luxurious and unusual. The final stage of application is waxing, which gives the coating a glossy Shine and protects it from damage.