Plaster for aerated concrete: which should be used
Plastering aerated concrete blocks is quite a responsible matter. Indeed, aerated concrete blocks - an economical and popular building material, which is characterized by high vapor and water permeability.
The vapor permeability of the supporting structure allows the building to "breathe", and the process of absorption of atmospheric moisture is blocked during the plastering of the walls. Therefore, everything must be done according to certain rules. How to plaster aerated concrete correctly, we will consider below. On the video in this article and photo you can see the most critical areas of this work.
The content of the article
Rules for the performance of plastering aerated concrete
The cellular structure of aerated concrete building blocks corresponds to the structure of foam blocks with different technologies for their production. The function of the gas-forming reagent in the composition of the aerated concrete mass is performed by aluminum powder. Thanks to this component, the cells in the finished blocks are kept open, in contrast to the foam blocks that are indistinguishable by appearance.
Attention: For interior and exterior decoration of facades from aerated concrete blocks, plaster is used, which includes slag or blast furnace sand. These components improve the thermal insulation properties of the finished coating.
Specialized stucco for aerated concrete is produced by both Russian and foreign manufacturers. There is not much difference in them.
Qualities that characterize stucco for aerated concrete
Before going to the building mix store, familiarize yourself with the basic characteristics of gas silicate plaster. Studying the basic principles of the choice of mortar will help you acquire plaster, which at a low consumption per unit surface will have high performance and aesthetic qualities. At the same time, the price will remain at the optimum affordable level.
The manufacturer indicates the list of indicators and their value on the container, and their value is listed below:
- Adhesion, or adhesion to the surface. This is one of the main characteristics of dry mixes. It is expressed in MPa (mega pascals) and indicates the strength of the interaction of the wall and plaster. The higher it is, the more reliable the finish is to fix on the surface of aerated concrete blocks. The most common and optimal adhesion index of dry mixes is 0.5 MPa. A number of manufacturers use other units, for example, kilogram-force. The correspondence of these values can be determined using conversion tables.
- The ratio of dry mortar and water in the preparation of the plaster. Normally, 9 liters of cold water are added per 30 kg of dry mixture (see Mortar for plaster: proportions when cooking) The solution is rather viscous and does not spread. It is beneficial if the mixture can absorb more fluid while maintaining a normal consistency. Due to this, a larger amount of the finished solution is obtained at the output.
- The thickness of the plaster determines the consumption of building material and the budget for finishing work. This value varies from 2 to 15 mm. If it is necessary to make a thicker coating, it is performed in several layers by special beacons.
- The time interval for using the finished solution is from 3 to 4 hours. It determines the speed of finishing and one-off volumes of preparation of the mass.
- Consumption per unit area determines the classification of efficiency classes. On average, about 8 kg of dry mix is consumed per 8 m2 with a plaster thickness of 2 mm.
- Price. Subject to the above characteristics, the cost of building materials should correspond to the average price category among similar products.
- The technology of preparing the solution. The proportions and the method of dilution of the mixture are indicated by the manufacturer on the container. In the process of mixing, the dry mass is poured into the prepared container. Water is added and the solution is kneaded. For the rational use of labor resources, the solution is prepared using a concrete mixer or a special nozzle on a drill.
Before buying plaster for aerated concrete walls, read the markings and pay attention to the date of production of the mixture. At the end of its life, the plaster loses its quality characteristics.
Define the application layer
How to plaster aerated concrete is determined by the volume of application of the solution. Its thickness is important to us. To do this, we stretch the line along the diagonals of the plane and look at the deviations of the plane. Do you need to plaster aerated concrete blocks on which layer you will immediately see.
- If the layer thickness is up to two centimeters, then you can simply apply the composition to the wall. In this case, you just need to make a primer on the surface and fix the mesh. This will make the coating strong enough;
- If the coating layer is more than three cm, then it will be necessary to do the installation of beacons. They will allow to withstand the plane when applying the solution.
Caution: Plastering walls of aerated concrete video will show you the application of the composition in one plane. So this will need to be determined before starting work.
The technique of plastering an external aerated concrete wall
When carrying out facade works, stucco on aerated concrete for external surfaces is used. After all, there will be increased humidity and temperature changes.
These materials are characterized by high wear resistance, resistance to external atmospheric factors and biological pollution. Everything can be done completely with your own hands.
Note: An important role is played by the aesthetics of the finished coating. Indeed, finishing work is carried out not only to improve performance, but also to improve the aerated concrete wall.
Plastering aerated concrete walls begins with the preparation of the desired composition. The mass must be uniform. For kneading, it is best to use a construction mixer or a drill with a nozzle.
Dry the mixture and mix until smooth. The viscosity of the plaster should be optimal for easy and quick application, distribution and fixing on the surface without smudges and stratification.
The sequence of applying plaster when ennobled facade of aerated concrete:
- Block surface preparation. At this stage, the wall is thoroughly cleaned of construction debris, mortar particles and adhesive materials, dirt and grease deposits on the surface of aerated concrete are removed. To strengthen the porous mass and improve hydrophobic properties, the wall is covered with a primer emulsion in one or more layers.
- Wall reinforcement. As a reinforcing base for the plaster, a special fiberglass building mesh is used (see Fiberglass plaster mesh - types and scope) With its help, craftsmen provide reliable adhesion of the plaster layer to the supporting structure. In addition, small mesh cells allow you to evenly apply a thin layer of finish. Due to this, the consumption of building materials and the costs of the owner are reduced.
- Application of rough plaster on aerated concrete wall.
- Finishing the building. Thanks to the introduction of fine sand into the finish, the surface is smooth and smooth.
- Painting of the plastered facade. Coloring improves esthetic characteristics of the house. For this purpose, breathable paints and varnishes are used for outdoor work.
- Application of additional water repellent held a year after the end of the whole complex of finishing works.
When performing finishing work on aerated concrete withstand temperatures from +5 to + 10 ° C. To comply with this, weather factors are taken into account when applying the external plaster.
Seasonality of work is an important rule in professional construction. Thanks to the special composition of the plaster and the technology of its application, the aesthetic and functional properties of houses made of aerated concrete blocks are improved.
Interior decoration of aerated concrete blocks
The process of plastering rooms in a house from aerated concrete includes the same operations as finishing the facade. Due attention is paid to the quality and consistency of the plaster.
Plastering the internal surfaces of aerated concrete has a number of distinctive features:
- The thickness of the rough and finish plaster is on average two times less than on the outer wall;
- Fine dispersion of the mass reduces the number of defects, bumps and dents on the finished coating;
- Use a regular cement-sand mixture (see Let's consider how to plaster cement-sand mortar) not recommended: special plaster is used for aerated concrete building blocks based on cement grade with a high water resistance index;
- It is easier to maintain the necessary temperature conditions in the room, which means that work can be carried out at any time of the year.
Aerated concrete quickly absorbs moisture from the solution, which is why cracks form on the surface during drying, breaking the strength and aesthetics of the coating. Additional wetting of the surface or adding to the mass of excess water does not solve the problem.
These measures lead to the formation of condensation in the cells of the blocks. The room becomes damp and unfit for living. Therefore, for plastering a surface from aerated concrete, it is necessary to use a specialized mortar.
Plastering on aerated concrete is extremely necessary, because you will protect the room from moisture. Video wall plaster of aerated concrete and instructions will help to complete the job quickly and efficiently.
