Concrete is one of the most ancient building materials, the earliest examples date back to the sixth millennium BC. In those days, clay and lime were used as binders. Modern concrete with cement has been known since 1844, since then it has become the most used building material. He has a lot of advantages, but there is only one drawback - an unpresentable appearance. To improve design indicators, various mineral additives are used during the manufacture of concrete or its surface is painted.
We will not touch on additives, but let's talk about wear-resistant concrete paints for outdoor use.
Wear-resistant concrete paint for outdoor use
Outdoor concrete structures are exposed to various negative influences: precipitation, ultraviolet radiation, mechanical stress, cyclic freezing / thawing. In addition, it is a hygroscopic material that absorbs a large amount of moisture from the air or earth. And most paints react negatively to high relative humidity of surfaces.
Monolithic concrete walls
Due to such features of the operation of concrete structures, special paints for external work are subject to increased requirements.
Before applying paint, the walls are primed
Constantly high concrete relative humidity values complicate the operating conditions of coatings. During the development of new durable paints, manufacturers take this feature into account and take a set of special measures to increase the moisture resistance of paints. Various innovative additives are used, paints are made on the basis of polymers, etc.
It is important that the paint is moisture resistant
are made of concrete. Mechanical loads on such elements can reach high values, paints must withstand the effects of abrasive elements. The requirements for all other designs are not so stringent, which expands the range of possible dyes.
The paint must have good mechanical resistance.
This means not only ultraviolet, but also infrared. They also have a negative effect on all paint materials.Ultraviolet rays destroy intermolecular bonds, paint loses its plasticity and cracks and peels off at the slightest load, and infrared rays change its original shade. The problem is solved through the use of innovative additives. Heat rays change the original color of the paint.
Mineral-based dyes are used to increase stability.
Resistance of paint to sunlight is no less significant characteristic
Do not use oil paints to paint concrete surfaces; after drying, they become completely sealed. As a result, it is rare to see structures painted with oil paints, without cracks and delamination.
Water vapor permeability and water resistance are important properties that a paint should have.
Less dust accumulates on smooth surfaces - the development of vegetation slows down. In addition, they are easy to clean with ordinary running water. Strictly speaking, this characteristic is conditional. Much depends on the place of use and purpose of the concrete structure, and not on the properties of the paint.
The paint must be resistant to dirt
Outdoor paints can not be exposed to rain, drying time should be optimal. The longer it dries, the more likely it will be exposed to rain.
It is important to choose a paint with a low consumption
The choice is not very large - either quality or price. The fact is that the cost depends not so much on the manufacturer's brand as on the list of components. And it is almost the same for the same types of dyes from different companies.
Choose a quality paint, not forgetting about its cost
Due to this, not only the design characteristics are improved, but also the consumption is reduced. This advertising of manufacturers is rarely confirmed in practice. Concrete is such a difficult material for painters that they consider it a great success to paint it with high quality in two layers. In most cases, you will have to do at least three coats of paint.
Paint in saturated shades
Modern paints satisfy the requirements of consumers, now you can find materials in the sale that match operating conditions of concrete products.
If strict environmental requirements are imposed on concrete paints for interior work, then materials for exterior use may contain harmful chemical compounds. Due to this "relaxation" of requirements, manufacturers are able to create coatings with improved performance.
Depending on the base used and manufacturing technology, all concrete paints are divided into several types.
|Paint type||Brief performance data|
| They are made on the basis of polyacrylates and polymer derivatives, they dry quickly, they are resistant to prolonged direct contact with water. Do not emit toxic substances into the air, universal use.
Service life up to ten years, the material is elastic - it is not afraid of thermal linear changes in the dimensions of concrete structures. They have high indicators of wear resistance. The disadvantage is a negative reaction to low temperatures.
| A combination of primers and colorants, universal, are distinguished by increased moisture resistance. Two-component, have high adhesion to most building materials, including concrete.
Disadvantage - with prolonged exposure to sunlight, a slight change in color shades is possible.
|New materials differ in increased operational characteristics. They can be used in a wide temperature range, resistant to chemical compounds, including aggressive ones. Disadvantages - high cost and long drying time.|
| Has a rich color, most concrete surfaces can be coated in one layer - time and cost of painting work is saved.
Although practice shows that one layer is not enough. The paint can be applied in any way possible.
| Combine all the advantages of acrylic and silicone dyes, can be applied to concrete surfaces both indoors and outdoors. By cost, refer to the middle price segment. Due to the use of innovative additives, they are not afraid of harsh ultraviolet rays.
Silicone concrete paint
No matter how expensive and high-quality paint on concrete for external surfaces, if you do not adhere to the rules for performing paintwork, then it will not live up to expectations. And the manufacturer is not to blame for this situation. What recommendations should be followed in order for concrete painting to be reliable?
A very important criterion, the final results depend on the correct choice. Before buying material, carefully read the instructions. At the same time, pay attention to the following points:
Quick-drying paint for concrete "Unicom"
If you live in difficult climatic conditions, then the paint should be expensive and high quality. Don't skimp on the cost, repainting concrete will be significantly more expensive than purchasing paint at a high price. Additionally, familiarize yourself with the dye preparation technology and temperature conditions under which you can perform painting work.
Paints for concrete
Elements of fences, garden paths, details of facade walls and landscape design are made of concrete. Concrete paths are used in the most difficult conditions; only deep penetration dyes should be used to stain them.
For other designs, you can use paints that form only the top layer.
Practical advice. If you plan to make concrete paths in the garden, then the issues with their painting should be resolved even at the stage of preparing the solution. Various mineral dyes must be added to the mass, this is the only way to guarantee the long-term operation of concrete without changing the original characteristics. To reduce the cost of construction, fill them in two layers.
The first layer is made of ordinary concrete, and the second with dyes. The thickness of the second layer is within three to five centimeters. This is quite enough to achieve the required strength, and a three-centimeter layer of colored concrete has not been erased for many decades.
Freshly poured concrete paths, first coat without dye
Filled color layer, the drawing was made using a stencil
Painted concrete path
This method is considered optimal for another reason - concrete paths constantly absorb moisture from the ground, and the presence of moisture has an extremely negative effect on the adhesion performance. There are, of course, modern primers that make it possible to more or less reliably waterproof paint from wet concrete, but in terms of their effectiveness they are much inferior to the above recommendation.
All other concrete structures are operated in more gentle conditions, painting requirements are less stringent, it is allowed to use any dyes for external work.
Concrete has a negative property - insufficient strength of a thin top layer. Even after running a hand over the surface, microscopic particles of material remain on it. This characteristic does not negatively affect the strength values, but can create problems during dyeing. To minimize negative effects, concrete surfaces should be carefully prepared before painting.
Scheme of repairing concrete walls with repair mixtures
Embedding reinforcement in concrete walls
If it has oily stains, it is a big problem. Detergent will not get rid of them, as some inexperienced craftsmen promise. Why? First, the oil penetrates very deeply into the concrete; it is almost impossible to "get" it out of there. Secondly, effective detergents contain acids or surfactants. Both the first and the second have an extremely negative effect on the strength of the material.
In these places, it becomes brittle, gradually crumbles under light loads, as a result, the paint will surely fall off in the cleaned area. This means that it is impossible to clean the oil from the thickness of the concrete layer, and the remaining oil will constantly rise to the front surface due to the capillary effect. The consequence is the same negative - the paint in these places will certainly peel off. If an oily stain is found, then it must be removed together with concrete to a depth of 2-3 centimeters. Next, seal the depression with fresh mortar, wait a few days until it completely hardens, and only then continue painting.
Applying repair mortar
How to prepare the surface? First of all, let's say that pure concrete is very rarely painted; the top leveling layer is subjected to such actions. And it is made from a cement-sand mixture. It needs to be prepared "greasy", the proportion of cement and sand is about 1: 2. By increasing the amount of cement, the sand is held much stronger. After the screed hardens, it should be thoroughly rinsed with high pressure water.
Cleaning the wall
Do not be afraid that a high pressure can wash the grooves, if this happens - you are in luck. This means that we managed to find a weak point and we can take timely measures to eliminate it. Otherwise, it would have manifested itself anyway, it would have been necessary not only to close up the depression, but also to renew the paint. And it will not be possible to make the patch invisible, it will differ significantly from the old paint for many reasons.
Applying a primer on concrete
Be sure to use good quality special primers.
On concrete surfaces, primers perform two tasks: they bind together the smallest particles of material and prevent moisture from entering between the concrete surface and the first layer of paint. There are two types of primers depending on the substrate:
Unlike polyurethane, they do not penetrate very deeply, but have better indicators of physical strength. For the price refer to the expensive segment.
Choose a primer according to its characteristics and the specific application of the paint.
Acrylic deep penetration primer for indoor and outdoor use
Deep penetration primer
Do not violate the manufacturer's recommended preparation technology. As for the consumption, it will be significantly more than what is written on the packaging, buy paint with a margin.
Instructions for painting concrete walls
During the application of paint, it must be rubbed very carefully into the surface. The best option is to use a pneumatic gun. Particles of paint fly out of the nozzle at high speed, hit the surface hard and fill all micropores.
Painting with a compressor
An acceptable option is paint brushes. With their help, paint can be applied with force, which will also provide a reliable adhesion.
Disadvantage - work takes a lot of time and physical effort.
She is also a problem of painting concrete with brushes. During the rubbing of the material into the surface of the structure, grains of sand may peel off, you will have to remove them. To do this, you need to wash the brush in a clean solvent, which takes time. And the percentage of solvent in the paint is constantly increasing, a little liquid will always remain on the villi, the new place must be covered with an additional layer, otherwise the difference in shades will be noticeable.
How to paint the facade
The worst option is to use rollers. The paint does not rub into the concrete, but only spreads over the surface. Of course, it is faster and easier to work with rollers than with brushes, but professional painters strongly advise against painting concrete surfaces with them, and not only those located outside the building.
Painting the concrete facade with rollers
The general purpose of all paints and varnishes is not only giving the processed surface a certain look and color, but also its isolation from adverse external influences
Nuances of painting concrete surfaces
In many cases, there is no need to buy expensive concrete paints for outdoor use, you can make them yourself. In terms of reliability and durability of operation, they will not differ in any way from the factory ones, and in terms of cost, significant financial resources will be saved.
How to prepare the paint yourself?
Step 1. Take any primer, an obligatory requirement - it must penetrate deeply into the top layer of concrete. The optimal depth is 2-3 mm, but the deeper the better.
Proacryl-Primer - universal penetrating facade primer
Step 2. Use colored pigments, the proven Sniezka Colorex brand, but another one is possible, if there is confidence in its quality.
Pay attention that the manufacturer guarantees that the pigment is resistant to sunlight. The cost of the pigment is much lower than the cost of the finished paint. And you still have to buy a primer, otherwise the paint will fall off the concrete surface in a few months.
Color map Colorex
Colorant Sniezka Colorex
Making paint for concrete
Step 3. The first layer can be made a little thinner - it will be absorbed deeper.
Let it dry well; in good weather, two to three hours are enough for this. Do not be alarmed that, after drying, the external will be unattractive. After the second layer, the color will become more saturated. If this is not enough, make a third layer. There will be no shine on concrete surfaces, but don't be discouraged.
The main thing is not to have to repaint the concrete structures regularly.
Painting the facade of a house with a roller
This is a proven method of painting parapets, fence hats, decorative elements, paths, etc. All factory materials in 5-6 years (and this is at best) begin to flake off, complex repairs are required. It is difficult to remove old dyes; you need to use hand-held metal brushes. If you work with an electric grinder with a round brush, then there are great risks of surface damage.
Repairing them is not as easy as it seems. A thin layer of cement-sand mass does not stick to the surface, you will have to hammer the concrete to a depth of several centimeters and only then close up the hole. And then there is a chance that the joint between the new and old material will crack. We advise you not to rush to purchase factory dyes, but use the above recipe and make the paint yourself.
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