Stucco for concrete: decorative wall decoration
Prefabricated reinforced concrete and technologies for casting walls using fixed formwork allow you to build buildings of any number of storeys. Moreover, not only the strength of the supporting structures, but also the speed of their construction is of great importance. Indeed, in the final analysis, the price per square meter of area depends on the time spent on construction - and this is the main goal of the developer.
Concrete, as a wall material, is popular in private construction. In this regard, the question: "How to plaster concrete walls?" - It is regularly asked not only by the inhabitants of the panel high-rise buildings, but also by the owners of the land plots planning to finish the walls of the newly built house with their own hands.
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Concrete texture in room design
For many decades, stucco has been the main way to protect concrete from moisture and corrosion, but with the advent of hydrophobic impregnation of deep penetration, this issue resolved by itself. Of course, when it comes to facades, decorative stucco for concrete always remains relevant.
- But inside the buildings, it is now performed solely for the purpose of decoration or alignment (see Alignment of walls with plaster according to all the rules) - when there is a need to close the joints between the panels, and the walls are planned to be lined, prepared for painting or wallpapering. The mentioned types of interior wall decoration can be called traditional, but they are by no means the only prerogative in this matter.
- The texture of concrete itself is very attractive, and modern designers, as usual, have adopted it. For example, stucco walls made of concrete slabs can be made so as to not only leave in sight, but also highlight their joints and fasteners, emphasize small sinks on the surface, which, by and large, are manufacturing defects.
- Moreover, the plastering of the concrete wall may not be carried out at all - the concrete surface is simply covered with protective impregnation, and, as in the photo above, is left in sight as an accent. A similar design is typical for loft-style interiors, for modern art nouveau, hi-tech, industrial and techno styles.
- Surfaces are left unfinished in full or in fragments, creating an emphasis on only one wall. This goes well with masonry, smooth wooden panels - and even with the same plaster. Such a design most often involves not only walls, but also ceilings - all the more so in apartments, cottages and townhouses (see. Modern decoration of townhouses), they are almost always concrete.
- It all depends on the concept of style, taken as the basis for the design of the room - so whether to plaster or not, ultimately, decide the owner. We do not impose our opinion on any account - we simply inform the reader about new fashion trends, which, as in the case of clothes, are changeable, although based on unshakable rules.
Plaster for concrete
Many people are interested in how plaster is made on GOST concrete, and what requirements apply to its application with current standards. Let's look at the main types of mortars used for leveling and decorating concrete surfaces.
- Plastering inside living quarters is done mainly by plaster (see Gypsum plaster: use technology) or gypsum-lime mixtures, since their white color greatly facilitates the decorative finish. Before plastering a concrete wall, it is necessary to assess its initial state, and, accordingly, choose the right leveling material.
- Compared to brickwork, concrete walls are always smoother - in any case, when they are built from large-format prefabricated reinforced concrete panels. Therefore, in their preparation for further decoration, most often you can do without using the basic composition, and immediately use finishing putty.
In basic, or as they are also called, starting mixtures, fillers have a larger dispersion, which allows you to close up more significant defects. These include the differences in the planes of two adjacent plates, which is most typical for ceilings, joints between panels, bumps, cracks in concrete with an opening of more than 2 mm.
Sand concrete mixes
To seal such significant defects, a better material than sand concrete, simply can not be found. This is a dry building mixture consisting of Portland cement, washed fractionated sand and additives that regulate the plasticity of the mortar and the time of hardening of the screed. Most often, carbonate lime is used as an additive for stucco mixtures.
Depending on the brand of cement and the size of the sand, the finished solution has different technical characteristics, and may have brands M150, M200 and M300. In general, sand concrete mixtures are conventionally divided into three subgroups: with a small, medium and large fraction of the filler. For mixing plaster mortars, a fine-grained mixture is required in which the sand fraction does not exceed 1 mm.
- In principle, to level the surface of a concrete wall, the strength of the screed corresponding to the M150 brand is sufficient. But when plastering some structures, the strength of which is subject to particularly stringent requirements, M300 sand concrete may well be used.
In private construction, such mixtures are most often used for plastering basement walls (see Cellar, underground or basement plaster) and facades. Inside the house, it makes sense to plaster the walls with sand concrete where the surface needs to be leveled with heavy material: large-format tiles, natural stone, fiber cement or ceramic panels with glue.
Warm plasters
Speaking about how and with what to plaster concrete, one cannot ignore the options for warm plasters. This is also a dry mixture, only in their composition instead of sand, light porous fillers are used.
Most often, they add granules of expanded vermiculite, balls of foam glass, perlite, expanded polystyrene. The filler occupies more than half of the total volume of mixtures, due to which the heat-insulating properties of the material are ensured.
- White cement or lime is used as an astringent in such compositions, or both. Their formulations are thought out to the smallest detail: in addition to the main components, there are many more additives that provide vapor permeability of the screed, water-repellent properties, and plasticity of the solution.
- Most often, warm plaster is used as an auxiliary method of wall insulation, and is applied not to the base base, but to a surface already insulated with plate material. Such plaster will help out in the case where it is not possible to use other types of insulation.
- The heat-insulating properties of such a screed with a thickness of 5 cm correspond to the properties of a layer of expanded polystyrene of the same thickness.This is an undoubted advantage of this material, but no less importance is attached to the decorativeness of the finished screed, which due to the large filler has an interesting grainy texture.
- That is why granular fillers are included in many types of decorative plasters: both facade and interior, and they can be not only dry, but also ready to use. When using granular mixtures, decorative stucco for concrete with your own hands turns into sheer pleasure, since there is no need to perform some technological operations.
- When plastering the surface, the solution is leveled along it with a trowel, and that’s it. It is not required to smooth and grind the surface of the screed, as is done when plastering with gypsum mixtures, since the granularity perfectly hides all the minor defects of the base base.
- To add decorativeness, the wall plastered with warm plaster is simply painted with vapor-permeable paint. So, the simplicity of applying the mixture to the surface to be trimmed can also be attributed to the number of positive qualities of the material.
But the most important advantage of warm plasters is their ability to let steam through them. It is this quality that makes them ideal for walls built from cellular concrete: aerated concrete, gas silicate concrete and foam concrete, of which the vast majority of private houses are built today.
Imitation of concrete texture
At the beginning of the article it was said that some modern styles of interior design suggest the presence of surfaces that are not plastered at all. We want to clarify that the room as a whole should correspond to these styles.
For example, the loft style design, in which this trend originated, is mainly used for spacious houses on two levels or large studio rooms.
- There, unplastered walls or ceilings look quite harmonious, which is balanced by expensive flooring, chic furniture, chandeliers and textiles. In standard rooms of a small area, with a ceiling height of less than 2.8 m, this will not look.
- Therefore, it is better to plaster a concrete wall or ceiling, which you have to admire from close range. This is also necessary from the point of view of room comfort, because even a simple screed has certain thermal insulation properties, improves acoustics.
- Let it be plaster imitating the same concrete, but you can put on it such a picture as you wish. In the process of decorating walls or ceilings, it is possible to smooth out all defects in the surface of concrete, or vice versa, to emphasize them. You can spray, cover the wall with mother of pearl - all that your soul wants.
The main role in this finish is played by gray color with a great variety of its shades. It is neutral, and combines wonderfully with almost any other color.
That is why concrete texture has become so popular! Its color is determined by the color of gray cement, and in order to ennoble an existing concrete wall, there is no better way how to use microcement-based plaster.
Plastering technique
There are no special difficulties in comparison with conventional plastering. On the contrary: in the process of preparation, only significant surface imperfections are closed: joints, cracks, potholes. Minor defects in the form of shells and small chips can not be touched, as they will participate in the design.
So:
- The main thing is that there are no soot, rust, oil, mold stains on concrete. This is important, since it is impossible to cover them up - after a while they come out. Recommendations for removing stains of one origin or another can be found on the Internet.If this is all right with you, you just need to remove dust from the concrete surface and soak it with concrete contact.
- After the impregnation has dried, plaster can be applied. If you purchased exactly the option to simulate the texture of concrete, then it will most likely be ready for use, and already tinted in gray. Although it is possible to make a coating with a texture similar to concrete using any texture plasters.
- They are usually sold in white, which makes it possible to show imagination and color the mixture. Before you make any texture on the surface, first apply the first layer of plaster, tinted in accordance with the main background of the picture.
- It is applied to the prepared surface with a Venetian trowel, smoothed thoroughly, and then, until the layer maintains plasticity, it is machined. To do this, use a "1000 lines" metal brush or other improvised tool with which you can make small sinks on the screed.
- Now you need to give the plaster a little time to set, then the structured layer is compacted with the same trowel. On the surface, barely visible shells remain - almost exactly the same as on real concrete. After about six hours, you can do directly decorating the surface.
- First, a transparent Venetian wax is taken, which, after diluting 1: 1 with water, is applied with a mclaw brush to the plastered wall. It will dry in two hours. The next layer will already be colored, also gray. It is applied with a brush, and then rubbed well with a sponge and left to dry. Now you can directly form a concrete pattern.
- It can be stripes, streaks, stains, splashes - all that is enough for your imagination. Decorative material is tinted in a more saturated color, and applied with narrow stripes with a regular dishcloth. Using a large, large-pore sponge, shade this strip, creating the effects of aging or scuffing. At the end of the finish of the fragment, it is polished with a light touch and lingering movements of the trowel.
- Such decor can be performed not only on panel concrete, but also on block masonry. Moreover, when plastering, the joints between the blocks do not close, but are left in sight. You can go the other way. If the base surface has too many irregularities that require a thick layer of plaster, it is easier to sheathe it with drywall, and already decorate its surface with concrete.
Many do just that, highlighting the joints between the sheets, making round or square holes in them that simulate fasteners. At the same time, the wall or ceiling looks like a drawn sheet, and it seems that it is mounted from flat concrete slabs of a small format.
