Not all finishing processes can be called easy. The development of technology makes it possible to make them not so physically difficult, and/or reduce the time and improve the result. But since the materials and technologies are new, many conjectures and errors in use arise. Today we will figure out what Concrete Contact is, what it is needed for, and how to use it correctly.
Primer developers
This composition has about a dozen name options: Betokontakt, Beton-contact, Betonokontakt, contact-soil, soil-contact, etc. The inventor of this primer is the German company FEIDAL. In any case, this is exactly what is indicated on their official website, and since no one has yet disputed the information, this fact can be considered true. The original name is Betokontakt, in Russian - Betokontakt. Among the people, “Betonokontakt” has taken root more, since it is most often applied to concrete. So, strictly speaking, the composition of only this company is original.
Feidal was the first to market a primer to improve adhesion to poorly absorbent substrates
However, any company that produces building mixtures has a similar composition with the same or very similar name. Most likely, the changes in the name are deliberate so that charges cannot be brought. In general, for the consumer it is not so important who came up with this composition. It is important that it fulfills its functions.
Compound
Each company adds something of its own to the composition, but Betokontakt in any variation contains the following components:
- Acrylic dispersion (copolymers). The basis of the composition, which is responsible for adhesion. It is this that leaves a sticky layer after drying. The quality of the primer largely depends on the quality of this component.
- Natural fillers. Usually quartz sand, but there are options. Creates a rough coating, which increases adhesion to the next layer.
- Supplements Give special properties (water resistance, antibacterial, etc.).
Some companies add dye. This is to make it easier to control the application and not leave bald spots. By the way, you can add it yourself to formulations without dye.
One of the variants of the name “Concrete-contact”
As you can see, Betonokontakt does not contain harmful substances, has a neutral acidity level, therefore it does not react with alkaline materials and does not contribute to the oxidation of metals. Thanks to this ability, it can be used under both cement and gypsum plasters/putties.
Purpose and scope
Concrete contact is a special type of primer for substrates that do not absorb water. If plaster is applied to such bases without prior preparation, it will most likely fall off when drying, since the surface of these bases is usually smooth and there is simply nothing for the plaster to cling to. To prevent the plaster from falling off, use Beto-contact. And it really works, but you just need to know when it is needed.
Operating principle of Concrete contact
The composition is not cheap, and it is recommended to use it anywhere. In order not to waste your money, you should know exactly its properties and scope of application. In general, information is on each can, but sellers (and some builders) advise a different use. But not everyone needs to be trusted.
What surfaces to apply to?
Concrete contact forms a sticky, rough layer with abrasive inclusions on the surface. Plaster/putty also adheres well to this layer. Abrasive particles - grains of sand or crystals - provide additional support for the finishing layer. In general, the task of Concrete Contact is to increase adhesion to complex substrates. But not to everyone.
What should Betonkontakt be applied to? As already mentioned, it is intended for substrates that do not absorb water. There are not many of them:
That's what Concrete Contact is for. There are no other recommended surfaces. Tips for applying to plaster under putty, under decorative plasters- this is all unnecessary. There is no need for this processing, because only the cost increases, but does not affect the result or only worsens the situation. Putty will work great on fresh plaster, just like other finishing materials.
Option from Prospectors - Beton-Contact
There is one piece of advice: it is better to use concrete contact with coarse grain if you apply plaster and with fine grain for putty.
Moreover, the advice is to apply Betokontakt to wooden and metal surfaces- this is precisely in fragments. For example, beams, protruding parts of structures. This is again the moment where a bookmaker is needed. For plastering wooden walls There are other technologies, and if there is only a fragment, it is advisable to use this composition.
Is concrete contact necessary over oil paint?
Finishers also use Betonkontakt over oil paint. Most people advise removing the paint anyway, because with or without concrete contact, the plaster under its own weight can separate from the paint. If the composition is firmly ingrained and cannot be removed by any means, you must:
In this case, it is also clear why Concrete Contact is needed and how it works. But it is quite possible to stop before the first application of Concrete Contact. If there are notches of sufficient area, both the plaster and the tile will stick. Use a suitable primer to fill any “chips” in the wall and, once dry, apply the next material.
Olimp has designated its Contact-Grunt as a product for decorative plasters and ceramic tiles
Many people assume that the sticky surface that Betokontakt leaves will hold better. In general, it works, but only if you do everything as written. And yes. Drying is complete and final. The expiration date is indicated on the can and differs depending on the manufacturer. The shortest drying period is 3-4 hours for Betonkontakt Fedal, the longest is about 24 hours for some cheap ones.
Where you should absolutely not use the composition
It is important to know not only why Concrete Contact is needed, but also where it is not needed and even harmful. For example, you should not listen to advice to saturate loose or loose substrates with the composition. This requires other deep penetration primers. And Betonokontakt sticks to a smooth surface without particularly trying to penetrate it. It makes no sense to cover whitewash, ordinary fiberboard with a loose structure, gas and foam concrete, plaster, etc.
Betokontakt is often purchased for priming a wall or floor before laying tiles. If the surface absorbs water, you should not do this. And that's why. Look at the characteristics of tile adhesive and BC. The glue has an adhesion of 0.8-0.9 MPa, and BC has an adhesion of 0.4-0.5 MPa. That is, by adding a layer of concrete contact to a normally absorbent base, you are worsening the situation at your own expense, and considerable money at that. Although some manufacturers write in the instructions that the composition can also be used for laying tiles. But the situation with adhesion is similar...
For outdoor and interior work can be used over old paint (written in the description)
If you want to ensure that the tiles do not fall off, take good glue. Yes, it is more expensive, but a pair of BC + cheap glue costs no less, and the result is unpredictable. If in doubt (not too much solid foundation), it is better to use a deep penetration primer and/or a better adhesive. It is usually positioned “for difficult surfaces” and holds tightly, as it penetrates deeply into the base.
The use of Betokontakt will do more harm than good when applied under. Cement ones will have worse adhesion than they could have, and gypsum ones will simply have to be “pulled.” They practically do not spread on the sticky base. The result is cracks, swelling and other very unpleasant moments. These are not the surfaces and cases for which Concrete Contact is needed.
What not to do
If you wish, you can find reviews or videos that say that the plaster/tiles have fallen off from Betonkontakt. To prevent this from happening, apply primer only to recommended substrates. In addition, you should not do the following things:
And for Betonokontakt to work, it must be “real”. There are a lot of fakes, so you have to be careful. And to be sure, you can check. Pre-treat a small piece of wall with BC according to the instructions. Apply the planned layer of plaster/putty. Wait until it dries and try to tear it off. If everything is done correctly, nothing will work out for you. They say that high-quality Betokontakt allows you to apply plaster even on glass. By the way, you can try it.
What to apply
You need to not only know why Concrete Contact is needed, but also how and with what to apply it. It just seems like there is nothing complicated about it, but try it first. The composition is often thick, approximately like kefir, and sometimes thicker. Moreover, it contains grains of sand and crystals, which it is very desirable to distribute evenly over the entire surface, and not collect in one place. In general, it's not that simple. There are some tips:
There is one more trick - attach a brush or roller to a stick about a meter long - and you don’t need a stepladder when working on walls, and keep yourself away from yourself - fewer drops will fly onto your clothes and into your face.
Manufacturers and possible replacement
As already said, from almost any manufacturer building mixtures there is Betonokontakt, Beto-Kontakt, Beton-Kontakt or something similar. If you like other blends from this manufacturer, it makes sense to try this one. There are local companies that good quality products are presented only in some regions. So not everyone is included in the list, but those who have a wider “coverage”. According to reviews, I liked working with Betokontakt from the following companies:
The list includes companies operating in different price segments. The more expensive ones usually apply a little better. Cheaper ones will have to be mixed more often, and they are more difficult to apply. When processing, try not to leave bald spots. If found already in the drying process, apply a layer and wait full time drying. This is better than having to redo the peeled off piece later.
People often ask whether Betonokontakt can be replaced with something. The only one possible variant— primer Ceresit ct-16. She gives similar effect, but the cost will probably be more expensive.
A few words in conclusion
Please read the instructions carefully before purchasing. Some compositions acrylic primers for smooth, dense bases they can be used under both cement and gypsum plaster. Others - only under plaster. Some are only suitable for internal use, others can be used outside. In the same way, there are compositions whose instructions indicate use on old paints, others are suitable for tiles... In general, carefully read the recommendations for use.
It would seem that what could be easier than understanding the principle of operation of a concrete contact and using it according to the instructions? Bought it, mixed it, applied it, and then do whatever you want: plaster, tile, apply any finish. However, practice shows that in reality everything is not so rosy. Repairs using concrete contact soils sometimes turn into real torture. In this article we will tell you which surfaces require the use of concrete contacts, and where you can do without it. We’ll also talk about the cost and economical application of this type of primer.
Among all the materials that are used to prepare surfaces for plastering or gluing tiles, concrete contact occupies a special place due to its versatility and unique adhesion - the ability to adhere to the most different surfaces. With the help of this innovative soil it is possible to carry out such complex connections absolutely different materials, like wood-glass, metal-tile and many others.
When processing dense, non-moisture-absorbing substrates, it simply has no equal. Previously, a special bandage made of fabric mesh had to be glued to a smooth concrete wall to hold the plaster. Now it is enough to treat it with concrete contact, and the surface becomes uniformly rough, capable of firmly holding not only plaster and tile adhesive, but also any other finishing materials. Even environmentally friendly, creating a particularly comfortable microclimate in any room, but very capricious gypsum plaster, will be securely fixed for many years.
Everything that is treated with concrete contact not only connects well, but also acquires special strength - the plaster fastened with it never cracks or crumbles when the hammer is used. You can safely drill holes - they will be very neat, not a single extra piece will fall off.
In addition to strength, surfaces treated with concrete contact acquire high water resistance, thanks to which they can function in conditions of high humidity. Also, a waterproof, uniform primer reduces the consumption of top coats. finishing materials.
Basic composition of concrete contact:
- Acrylic dispersion, which is the basic component that organizes the adhesion of surfaces.
- Quartz sand, which provides surface roughness (coarse-grained - for plaster or fine-grained - for putty).
- Cement.
- Compositions of chemical modifiers responsible for vapor permeability, hygroscopicity, resistance to mechanical and biological influences.
As you can see, concrete contact can be classified as an environmentally friendly, harmless material. Surfaces treated with it do not lose the ability to “breathe”. Bactericidal components prevent the appearance of mold, fungi and insects. The activity indicator of hydrogen ions in concrete contact solutions corresponds to neutral acidity, which indicates that they do not pose a corrosive hazard to metals and do not react with lime-containing solutions. Sometimes coloring pigments are added to the components to make it easy to determine where the application was and where it was not.
The full properties of each concrete contact, as well as the conditions and shelf life, must be described in the documentation attached to it, in support of which a certificate of compliance with the quality established by GOST standards is attached or presented upon request.
Attention! It is prohibited to use concrete contact that has expired its shelf life, as well as one whose structure has become heterogeneous and lumpy.
In practice, when determining which concrete contact is best to use, they rely on the following: specifications, How:
- fast drying time of the treated surface;
- degree of moisture resistance;
- duration of service life;
- cost standards.
If you need a complete description of concrete contact, it can always be found in the instructions
Working with concrete contact primers is very easy, you just need to follow some simple rules:
- The surfaces to be coated do not require special treatment, but dirt, grease, swelling and falling off pieces of old coatings must first be removed.
- Work must be carried out in the temperature range from +5 to +30. But for high-quality operation, the temperature can be from -40 to +60.
- Typically, the conditions for maintaining concrete contact require positive temperatures. However, now you can also find a frost-resistant solution that allows storage and transportation at -15 degrees, as well as a 5-fold freeze-thaw cycle.
- It is better to apply finishing materials on top of the concrete contact layer immediately after drying, before it becomes dusty (dust reduces adhesion). A delay of more than two days is already critical - a fresh coating needs to be applied.
For priming smooth, non-absorbent surfaces there is no alternative to concrete contact.
To prepare for finishing loose, crumbling, porous surfaces, it is necessary to strengthen them by impregnating them to a certain depth, which requires deep penetration soil. It can be used independently or before concrete contact. If you use only concrete contact, the consumption may turn out to be exorbitant.
Complex application or just a primer or concrete contact - which is better must be decided taking into account all the specific conditions separately for each case.
Concrete contact for external work: features and properties
According to their purpose, concrete contacts are:
- for interior work;
- combined - for internal and external.
Specialized compositions only for external use are not yet available. For this purpose, concrete contact is used, the instructions of which directly indicate the possibility of its use for priming the surfaces of the facade or foundation of a building for putty or plaster. At the same time, all the characteristics that determine concrete contact remain unchanged.
There is some disagreement about whether concrete contact should be used under cement plaster. Or why use it for foam blocks - after all, their surface is initially quite rough, and the structure is such that it requires a deep penetration primer more.
More often, for outdoor surfaces, soils containing coarse-grained fractions of quartz sand are used (expanded clay, marble, etc. chips are also successfully used), capable of holding heavy plaster.
When planning plastering and facing work on the outside using fastening layers of concrete contact, you need to remember that it only works at positive temperatures. When the temperature rises to more than 30 degrees (40 degrees for some brands), the properties deteriorate significantly - the uniformity of drying is disrupted. At temperatures below +5 degrees, concrete contact gradually turns into a viscous sticky mass that is impossible to work with (if the “frost-resistant” property is indicated, then it refers to storage conditions).
But when finished, treated with concrete contact and dried (concrete contact dries very quickly), any surface retains its properties in a wide range of temperatures and under any external weathering. That's why he great success used for conservation - when finishing work has to be suspended, for example, for the winter.
The price for universal concrete contact is not too different from the price for concrete contact for interior work.
Concrete contact for interior work: features and properties
Inside the building, concrete contact is applied as a primer for any surfaces:
- To prepare the ceiling for whitewashing.
- For floors - under any screeds, including self-leveling floors. Thanks to increased adhesion, you can make a screed without removing the old, durable tiles. Concrete contact - best processing before gluing linoleum.
- Before covering any walls and partitions with plaster, putty and any other finishing materials.
- To strengthen drywall - reduces its porosity, gives it water resistance, allows you to apply any paint to drywall, glue wallpaper and facing tiles.
For all surfaces to which concrete contact is applied, drying takes an average of 2-3 hours - this is very fast compared to other primers.
What also speeds up the renovation process is that it can be applied to old finishes: paint, gypsum plaster and even tiles. But provided that this finish is very durable. Otherwise, the unreliable layer must be knocked down.
Concrete contact works great in rooms with high humidity and steam formation: in the bathroom, kitchen, basement, laundry room, etc.
Attention! Concrete contact that accidentally gets on the skin can be easily washed off with water. But only until it dries. Therefore, all stains from it must be removed immediately.
Concrete contact primer from different manufacturers
There are not many manufacturers of concrete contacts in the world that produce high-quality products. Each of them has its own characteristics and production secrets.
The most famous is the Knauf company. Knauf Betokontakt concrete contacts with fine-grained and coarse-grained fillers are successfully used in a variety of areas and are very popular among consumers.
Another oldest world-famous manufacturer is Ceresit. Universal concrete contact Ceresit CT 19 among others useful qualities It is particularly effective when used for the tile-to-tile tiling technique.
The European leader is the Feidal concern and, in particular, its plant in Russia “Feidal Paints” produces concrete contact Feidal Super Kontakt combined use, which has proven to be indispensable when renovating old houses with multiple coatings of linseed oil and oil paint.
If there is a need or desire to carry out finishing work in a short time, then it would be correct to use concrete contacts from Bergauf or Starateli with latex additives, which are particularly distinguished quick drying for 50-60 minutes.
Concrete contact can be produced not only as a ready-made solution, but also in dry form. Thus, the universal-use dry concrete contact mixture “Axton” with marble chips instead of quartz sand has technical characteristics no worse than those of liquid soils. Its working technological feature is the possibility of application on unpolished and uncleaned surfaces.
The quality and reliability of concrete contacts is a privilege not only of well-known brands and historical enterprises. Eat modern manufacturers, successfully mastering innovative technologies and producing high-quality products that meet international standards and GOST requirements in all respects.
Depending on taste and financial capabilities, everyone must decide for themselves which concrete contact company is better to choose.
Costs of concrete contacts of different brands - is there a difference?
The consumption of concrete contact from a wide variety of manufacturers depends, firstly, on such qualities of the treated surface as:
- porosity;
- absorbency.
In Table 1 you can see the consumption rates of concrete contact for surfaces of different structures.
It can be seen that any primer per 1 m2 is consumed approximately the same.
There is a way to slightly reduce the consumption of concrete contact for porous surfaces - preliminary impregnation with a deep penetration primer and. Secondly, you need to keep in mind the influence of the size of the sand, expanded clay or marble chips included in the composition:
- concrete contact with fine-grained (0.3 mm) filler is applied in a thin layer;
- compositions with coarse particles (0.5-0.6 mm) - thicker, approximately 1.5 - 2 times larger.
Thirdly, the consumption is influenced by the characteristics of the recipe of each specific manufacturer. You can compare the average consumption values depending on the brand of concrete contacts in Table 2.
As you can see, there is a difference, although not very big.
For precise definition consumption rates using the probe method:
- a certain amount of concrete contact soil and the tool with which it will be applied is weighed;
- stands out (with chalk or adhesive tape) square meter surfaces and covered with primer to the required quality;
- the remaining solution and tools are weighed;
- the difference in the scale readings is found - how much is the consumption rate;
- the resulting value is simply multiplied by the total area to be processed.
How to buy concrete contact and not go broke on construction
Not a single professional will advise saving on priming surfaces with concrete contact. In order for the plaster, glue or topcoat to last long and firmly, the layer of such primer must be applied evenly, without gaps, and have sufficient thickness. The greater the thickness of the concrete contact layer, the better its adhesive properties are manifested. There is no point in saving here - you can lose much more by spoiling, for example, not cheap drywall, tiles and other materials that have fallen off.
Renovation work has its problems. In the first stages, if you are a beginner, many questions may arise. The first question is how to apply finishing materials to the surface? It often happens that after drying plaster mortar, the paint surface begins to peel off, the top balls fall off. It also happens that even the best glue is not able to withstand the tiles.
Thanks to the latest technologies A universal method has been developed for all of the above problems - this is concrete contact (primer - soil).
The material has good strength with concrete. The composition contains polymer materials, cement, sand and additional additives. To some extent, this is soil, which plays the role of a binding substance between the surface of the ceiling or walls and the coating material. Capable of increasing the adhesion of surfaces and finishing materials. Concrete contact has different price, depends on the manufacturer and packaging.
In order to achieve a high-quality repair, the finished plastered surface does not crack, water-based paint did not peel, the tiles did not fall off, the wallpaper did not peel off, it is necessary to use concrete contact.
This material is a primer that can make a smooth wall rough. Has a number of advantages:
- Dries quickly. 2 hours is enough to start the following finishing processes.
- Moisture resistant. Concrete contact is not afraid of moisture, it is a waterproofing substance, and when hardened it forms a waterproof film. Concrete contact primer is also used for floor screed, but in this case the moisture resistance will be unnoticeable. Goes well with lime. Thanks to this, it can be used in rooms with different humidity levels, even in bathrooms, garages, balconies, basements or entrances.
- It is a wear-resistant material. Manufacturers claim that finished coating made of concrete contact can last up to 70 years.
Thanks to such positive quality, this material is popular among specialist builders. For liquid composition sprayers and paint sprayers are used.
Composition and properties of concrete contact
Concrete contact is produced in 2 varieties:
- The filler fraction size is 0.3 millimeters - fine-grained.
- The filler fraction size is 0.6 mm - coarse-grained
The second class of factions is more often used when dealing with rough ones. finishing. Often the composition of the material contains porcelain stoneware or expanded clay. The material plays the role of plaster. The first option is used under the putty mixture. Various manufacturers(bitumen, bolars, vetonita, karoyed, lacr, kreps, rotband, unis, phoenix) produce different mixtures:
- Concrete contact is produced and sold in finished form. We can see this option in supermarkets in different containers (bucket, barrel).
- The second option is dry powder. To use it, you first need to prepare a solution and dissolve it in water.
The primer should not be used under wood (laminate), as it is an absorbent material. Recommended for use on glass, concrete, metal coatings, not all types of coatings, tiles, tiles. Also used for other options:
- For treating the floor before you need to fill the coating or make a screed.
- Before applying plaster or putty mixture to walls or ceilings.
- To reduce porosity, improve quality plasterboard sheets(hl), also use concrete contact.
- Before painting the floor, builders floor coverings cover the surface with concrete contact.
You need to work with the primer under universal conditions: warm temperature from + 5 to + 30 degrees Celsius. The material must be stored in a hermetically sealed package to prevent air from entering under the lid. The finished surface can be exposed to different temperatures. The material is manufactured according to GOST standards (quality certificate). Concrete contact soil can withstand temperatures from minus 40 to plus 55 degrees Celsius. Working with the material is required according to the standards.
In order to decide on the choice of material, let’s compare soil manufacturers.
| Name | Technical characteristics (properties) |
|---|---|
| Betonokontakt prospectors | The prospector brand has a soil composition highest category. Some compositions contain one of the main components - latex. Used for home interior, exterior finishing. Is safe for environment and man. Does not contain toxic components, environmentally friendly. This primer can strengthen and increase adhesion (adhesion) of the finished surface. Cannot be used for wooden (osb, fiberboard) coatings. Often used for old tiles, foam block, foam plastic, dense walls. This material is designed to provide the surface with a moisture-resistant coating. It has economical consumption: 1 square meter requires 200 g of soil. Dries quickly compared to others. It will take 2 or 3 hours to dry. |
| Betonokontakt Knauf | Knauf primer is used for internal, external walls. Goes well with gypsum plaster. It has high moisture resistance, so it is applied to surfaces before coating, which absorbs moisture. Often used for walls made of concrete or cement, painted with oil paint. Less commonly used for plasterboard sheets, aerated concrete blocks, foam blocks, penoplex, and heat blocks. Does not require any time or effort. They are popular among masters and beginners. Therefore, you can make repairs with this material yourself. You can use a spray gun, but you should not make a thick solution. With this method, the material consumption will be significantly less: 1 square meter - 300 g of mixture. The cost price is high. |
| Concrete contact ceresit | The Ceresit brand is in demand for interior decoration Houses. The primer can increase the adhesion of apartment walls to the material. Creates a waterproof coating. The composition contains mineral components, water-based dispersion, polystyrene, and specialized pigments. Often used for monolithic concrete, after which the surface is treated with soil, tile adhesive, plaster. Ceresit primer is a vapor-permeable material. To cover the walls, additional work no need to carry out. Manufacturers produce dry and ready-made mixtures. Ready-made ones are packaged in weights of 5 and 15 liters. It is not harmful to the environment and humans. Can be applied to uneven surfaces. Because of this, the material consumption is different, the maximum can be 0.7 kg per square meter. Compared to the previous brand, it dries a little longer - 3.5 hours. |
| Axton | It has good adhesion, so it can be used on unprepared surfaces. Sanding and priming are not necessary. The composition contains active ingredients: marble chips, quartz sand, acrylic substances, polymer materials. Working with this material is a pleasure, low consumption - 1 sq.m requires 300 ml of mixture. Quick-drying and waterproof. After 2 hours you can proceed to the next fake. Packaged in 3 kg, 20 kg. |
In addition to the above companies, there are analogues: bergauf, ceresit - ct19, knauf, litokol, prof, bettokont - lp55, aquastop, axon, alpina, begrauf, typhoon, eurolux.
Betonkontakt Seresit CT 19 (video)
Material consumption
Concrete contact primer can be used for different coatings. Based on this, the consumption of materials per 1 m2 will be calculated.
| Surface type | Characteristic |
|---|---|
| Low porosity | This type includes: old coating (paint), metal, concrete, ceramics, tiles. To cover the listed materials, the consumption spent will be minimal - 1 square meter / 0.25 liters of mixture. |
| Average porosity | Consumption of deeply penetrated soil. It will be higher than in the previous version. 1 square meter - 0.35 liters of mixture. TO this species include: concrete tiles, cement floors, bricks, monoliths, high quality concrete. |
| High porosity | For this type of surface, the Grant consumption is high, 1 square meter is 450 ml of the mixture. Despite the high consumption, before coating, polished concrete, building bricks, sand concrete are coated with special substances, which also have deep penetration. |
Application of concrete contact
Compared to other materials, concrete contact soil can be worked with without special tools. At the first stage, it is worth cleaning or washing the walls, ceiling, and floor from old coating or dirt. If the walls are painted, you can wipe off the paint using a spatula and water. Wallpaper can be easily removed with water. You need to wet the surface, wait a while and remove the coating. Next you should rub the walls with a wet smile, a rag.
Application of concrete contact When applying concrete contact, it is advisable to treat the walls with a regular primer. This will help completely eliminate dust and improve adhesion. The first layer of material must dry completely so that the concrete contact does not settle on the surface. Some materials are frost-resistant; they are used for the facade so as not to worry about the house in winter.
For the main work you will need a roller, brush or spatula.
For convenience, you can use a paint bath. Pour a large amount of liquid primer into a tray, take a small amount of the mixture onto a roller, and spread it evenly onto the wall in a thin layer with a brush. The finished layer must dry. Drying time depends on the brand of soil. Before use, carefully study the instructions, description, and rules of use. After a certain period of time has passed, the surface has dried, you can proceed to the next steps. There is no need to leave the coated surface on for a long time. During this period, the clean coating may again become dusty, which means that the tenacity of the next material to the surface will be worse.
There are times when, in the process of repair and construction work, it becomes necessary to veneer surfaces that are too smooth. For example, glue ceramic tiles to metal, glass or concrete. In the old days it changed design solution, or cumbersome and complex measures were taken to prepare such surfaces. Good modern technologies came to the rescue.
Was created relatively recently new material- this is concrete contact. Something between glue and primer, or rather an adhesive primer. It makes any smooth surface rough. The task of this material is not to connect the finish with the base, but to create Better conditions to bind them together using traditional glue.
Composition and properties of concrete contact
Each manufacturer keeps the exact recipe of their creation secret. But the main technical characteristics of concrete contact primers of various brands, say Knauf or Ceresit, are similar. The material consists of a polymer binder and fillers, which include quartz sand, talc and others. The primer is usually tinted a faint pink color so that untreated areas can be easily seen during application.
The composition of concrete contact and the ratio of components affects the area of its use. Some primers are designed to treat internal surfaces, others - for outdoor work. But there are also universal compositions that can be used in any circumstances. The material is almost irreplaceable due to its unique ability to improve adhesion. Its main properties are listed below:
- Concrete contact soil is recommended for use on vertical and horizontal surfaces. It is able to create the best conditions for adhesion of any materials to each other.
- High resistance to moisture penetration is due to the formation of thick film. This property allows the soil to be used as a waterproofing material when arranging floors.
- How long does it take for concrete contact to dry? Fast enough. Typically, 4-6 hours are enough for complete drying, depending on the quality of the surface being treated. More porous ones dry longer, denser ones dry faster. The speed of drying is also affected by temperature and humidity environmental conditions. Where humidity is high, it is better to wait a day before continuing work. It is recommended to maintain the same time when using concrete contact for external work. But you cannot leave the treated surface for a longer period. Since it may become covered with dust, adhesion will be reduced.
- Long service life. Practice has established that with strict adherence to processing technology, the surface does not change its properties for 80 years.
- Excellent workability. The consistency of factory-made concrete contact allows you to work with it using a roller, brush, or mechanical devices. It easily lies on the surface and is distributed over it.
Thanks to these characteristics, the primer can be used equally effectively by both seasoned finishers and novice craftsmen.
Material consumption
The theoretical and manufacturer-recommended consumption of concrete contact per 1 m2 of area is 300 grams. However, this figure may change significantly with actual use. Material consumption can increase to 500 g/m2 with:
- The ability of the treated surface to strongly absorb moisture.
- Finishing vertical surfaces with heavy materials. For example, natural stone or large-sized ceramic tiles.
- Treatment of surfaces with high porosity (brick, cellular concrete, wood).
And, on the contrary, the consumption of concrete contact can be reduced to 160 g/m2 when used on low-porosity or dense areas.
The required amount of material for processing a specific surface can be determined experimentally. To do this, you need to take a certain amount of emulsion, for example 0.5 kg. Then apply primer to 1 m2 of wall area or any workpiece. Weigh the remaining soil and calculate the difference. It will determine the actual consumption of material. For a more accurate calculation, you can take into account the adhesion of material on the tool. It must be weighed before and after work.
Application of concrete contact
Despite the fact that the primer is intended to improve the adhesion of any materials, the instructions for using concrete contact recommend pre-preparing the surface. To do this, it should be freed from dust and dirt. Any crumbling or flaking areas must be removed, and uneven areas must be smoothed out with plaster. Perhaps the only base to which the primer does not stick is greasy spots. If such places are present, then they must be washed with soapy water, dried, degreased, dried again and only then covered with emulsion.
If there is a need to save concrete contact when treating surfaces that cannot be thoroughly cleaned, then it makes sense to first coat such an area with a regular deep penetration primer. And after it dries, start working with the main composition. Since it is recommended to apply concrete contact using conventional tools and methods, there are no difficulties in this, but there are some nuances.
- During finishing work, it is necessary to disconnect the room from electricity to avoid accidental wetness of the wires.
- It is necessary to ensure acceptable storage conditions for the primer at positive temperatures and prevent it from freezing.
- Work should be at temperatures above 15°C.
- The primer should be mixed thoroughly before use. It should have a uniform consistency, reminiscent of thick sour cream. If the emulsion is too thick, it can be diluted a little with clean water.
- As the main tool, you can use a roller, a wide brush or a brush. You can work with a large stainless steel spatula or even a spray gun. The choice of tool is not important - the more convenient it is, the more you should act.
The primer is applied in a continuous, uniform layer. A complex surface can be covered with two layers. The next layer is applied only after the previous one has completely dried.
Where is concrete contact used? This is a unique means of providing high level adhesion for all materials. This soil is environmentally friendly, does not emit harmful substances, and therefore is suitable for use in premises for any purpose. But it won’t hurt to ventilate the room after finishing the treatment. Special and universal compositions are also used before cladding external walls. This significantly improves quality facade works, and increases the service life of the finish.
If this is your first time doing renovations, then you should think about the difficulties that await you when doing the work yourself. One of the problems that may arise for you is finishing smooth surfaces, namely ceilings and walls. It often happens that plaster or paint applied, for example, to concrete, falls off after drying. This is a very unpleasant moment that, perhaps, all novice “repairers”, as well as any professional, want to avoid, because this will negatively affect his future work. Concrete contact can help solve this problem. It will save your renovation and protect you from possible troubles, such as fallen tiles or wallpaper coming off the walls. The composition of such a primer includes cement, polymer fillers, sand and special additives. Acting as an adhesive for all kinds of finishing materials, it acts as a binder for them with the surface of a wall or ceiling, or, in professional terms, it increases the adhesion of layers. Therefore, if you need confidence that, after drying, the plaster will not move away from the wall, you should use concrete contact during the repair process.
Used on smooth surfaces such as: drywall, monolith, ceiling concrete plates, blocks, etc., thanks to its properties it improves structural features these surfaces. When they are processed with concrete contact, the wall or ceiling ceases to be perfectly smooth, but acquires a roughness that looks like sandpaper, which allows next layers better to connect with base surface. Also, if the surface of the ceiling is treated with concrete contact, the plaster on it will not crumble for a long time, while on the walls, treatment with concrete contact will allow you to fix the plaster, wallpaper, and tiles. This will allow you not to think about new repairs for a long time, because both the painted ceiling and the glued or plastered walls will retain their original appearance for a long time and will delight you with their durability.
This primer can also be applied to old paint(if, of course, it is not separated from the walls), wallpaper, wood and even glass. This is a universal product, suitable for all surfaces and is very good decision for seemingly hopeless situations. It is moisture resistant, does not have a strong odor, and dries quickly. It is also important that the concrete contact soil has antiseptic properties.
Traditionally, the soil is “concrete contact” Pink colour, and it must be homogeneous. After all, its heterogeneity indicates low quality soil, or even the expiration of its shelf life. Like any other finishing material, the primer is applied to a surface that has been previously cleaned of dust, paint and oil. If the surface is dusty, you can walk over it with a spray bottle of water, and after waiting for the surface to dry, start applying primer. The instructions for applying concrete contact to the surface are simple: apply it to the wall or ceiling with a brush or roller in one layer like any other primer. The average consumption is half a kilogram per square meter of surface and directly depends on the type of surface. The “drier” the surface, the greater the material consumption, accordingly. As a rule, applying one layer is enough, which dries within four hours at room temperature and moderate humidity. It is advisable to apply subsequent layers of finishing materials (plaster, wallpaper, tiles) immediately after the primer has completely dried in order to avoid its contamination and, as a consequence, deterioration of adhesive properties.
As for storing concrete contacts, the conditions for this should be normal - room temperature or positive temperature (garage, utility room). Under these conditions, it can be stored for up to a year.