Aerated concrete blocks are a masonry material that is increasingly chosen by consumers as a building material for the construction of buildings and structures. This is true for individual construction, and for industrial. It cannot be said that aerated concrete is a novelty. It is a kind of cellular concrete and is an artificial stone, characterized by a uniform distribution of spherical pores throughout the volume. The material has a solid operational resource, however, it requires mandatory certain protection from external influences. Facade plaster on aerated concrete is a great way to increase the durability of structures, giving them a presentable pleasing look. In our opinion, a masterful homeowner can handle such work on his own. Whether it is within the power of you specifically, we propose to decide after reading this information and recommendation material.
What you need to know about aerated concrete
To understand the essence of facade plaster on aerated concrete, you need to know the technical parameters of this masonry material. So, we have already focused your attention that it has a porous structure, and any pore can be 1 to 3 mm in diameter. This feature of aerated concrete gives it both positive and negative properties.
Important! Vapor permeability is another very important parameter of aerated concrete. It can be used both for the benefit of the structure and for harm. So, this quality can serve as the basis for creating a favorable microclimate in the house. If, however, the exterior finish is not done correctly and the vapor permeability of the walls increases in the direction from the outside to the inside, then this will inevitably lead to the opposite result.
Also, one more aspect cannot be ignored - aerated concrete is characterized by low bending strength. With this in mind, if it is chosen as a material for the construction of walls, then the following measures are mandatory:
- monolithic foundation device;
- reinforcement of both the masonry itself and the ceilings, as well as the truss structure.
These technical subtleties are most directly related to the topic of facade plastering on aerated concrete, since only when they are taken into account can one count on obtaining a durable beautiful exterior wall finish.
What should be the plaster
Another factor that should be emphasized when considering how to plaster the facade of a house from aerated concrete is the characteristics of the plaster mixture. The modern market provides the consumer with unlimited freedom of choice of finishing materials, including facade plaster.
However, whichever brand is preferred, plaster that is “suitable” for application to aerated concrete should have the following qualities:
- High compressive strength.
- Resistant to temperature fluctuations.
- Resistance to external factors.
- Excellent adhesion.
- Frost resistance.
- Vapor permeability.
In principle, these are general requirements that most special mixtures for application on surfaces made of aerated concrete and other cellular materials meet. To understand what is "what you need" when choosing, you must carefully study the packaging of the goods. If there is a corresponding marking, then everything is in order.
By the way: high-quality facade plaster will be accompanied by certificates of compliance with the highest European quality standards. This will also be reported to the consumer by a special designation on the packaging.
Before plastering the facade of a house from aerated concrete, you need to understand what budget you can allocate for such an event. If we make a comparative analysis of plasters, then it will be obvious that the compositions for applying specifically to aerated concrete are somewhat higher in cost. We want to warn you, this is not a reason to save money and purchase cheap analogues of a dubious "reputation". In practice, it has long been proven that both the appearance of the facade and its performance will suffer, including the following:
- violation of air exchange;
- crack formation;
- high humidity;
- plaster peeling, etc.
Facade plaster on aerated concrete: an algorithm in a nutshell
When applying plaster on a porous material, the following sequence of operations must be observed:
- High-quality exterior finish of aerated concrete walls necessarily involves priming the surface with a special composition.
- Using self-tapping screws on the facade, you need to fix a reinforcing mesh made of fiberglass resistant to alkali.
Important! The use of a special reinforcing mesh is a very important factor, since the traditional one will collapse after a very short time, which will cause the formation of cracks in the plastered surface.
- A special porous plaster mixture is applied to the walls, characterized by high vapor permeability. It is important to take into account that the thickness of the outer layer of plaster should be twice as thin as the thickness of the interior finish.
- A fully stabilized plastered surface is given a decorative finish by painting with a special vapor-permeable paint in a chosen color. As an option for facade finishing - applying a special three-layer external coating.
- After 1.5-2 years, a well-aged layer of plaster on aerated concrete in order to increase the service life of the facade should be subjected to hydrophobization.
Attention! Plaster mixtures with the help of which surfaces of increased vapor permeability are arranged involve the inclusion of light perlite sand, as well as slaked lime, in the formulation.
Tools and technology - "classics of the genre"
Plastering on aerated concrete does not require any special tools, everything is as usual:
- container for mixing the solution;
- construction mixer or drill with a special nozzle;
- trowel or trowel, or plasterer's ladle.
The dry mix according to the manufacturer's instructions (do not forget to carefully study what is written on the package) is kneaded with the addition of water and brought to the desired consistency. The resulting composition is applied to the wall with a "throw", leveled and rubbed with a grater. To remove excess plaster from large surfaces, a half-ter is used. The leveling of the wall surface occurs with the use of beacons - the same as in the classical plaster technology. The contraction of the solution between the guides occurs through the rule.
Important! The final stage of the work is a quality control check. For these purposes, a rail commensurate with the height of the ceilings of the room is suitable. It is applied to the surface both horizontally and vertically, which allows you to highlight possible defects. Permissible non-critical error - 6-7 mm.
If we talk about obtaining an absolutely even surface of freshly plastered walls, then an additional procedure is smoothing approximately 24 hours after applying the plaster. Pre-work area must be wetted - slightly. And only after that, as we have already indicated above, is the paint specially designed for aerated concrete painted.
The most common mistake in the design of the facade
Practical experience shows that often construction work during the construction of a house, including from aerated concrete blocks, ends closer to winter. Further, according to the logic of things, the design of the facade should be carried out, and already in the winter period it is the turn of interior transformations. This working scheme will be correct in many cases, but not applicable to buildings made of cellular aerated concrete blocks.
Attention! Facade plastering should be carried out only after all “wet” interior finishing works have been completed without exception - plastering of structures, pouring screeds, puttying.
In short, it is possible to “make” a facade only after excess moisture has been completely removed from the premises. In order to understand the importance of this moment, it is necessary to know the "physics" of the processes.
- So, in any case, if the decoration of the walls, ceiling or floor cake is associated with solutions in the room, which means that one of the main ingredients is water.
- It gradually evaporates and is removed through the ventilation system and through the pores in the walls.
- If these mechanisms are launched at a time when the external environment is in a low-temperature regime, then water in the vapor state will begin to condense in the wall structure or at the border of the outer area of aerated concrete and facade plaster.
- Further, freezing of the collected moisture will inevitably take place and, accordingly, the destruction of the facade finish. Moreover, it is worth noting that a similar fate awaits even plaster of the highest quality.
- As in any business, it is not enough to use only high-quality materials, a prerequisite for success is the exact observance of the work technology, taking into account the climatic characteristics of a particular region.
In principle, that's all the information that a "handy" homeowner needs to give a building made of porous masonry material a presentable and functional look. We hope that the topic of how to plaster the facade of an aerated concrete house for our readers is now clear in all aspects. Also, we recommend that you familiarize yourself with the thematic video.
