Primer consumption Betonokontakt Knauf per 1 m2

Preparing walls for painting, plastering or other processing always implies the maximum leveling of the base. If, formally, according to the descriptions of the compositions, it turns out that they can also lie on uneven surfaces, it is not worth the risk once again. When finishing concrete, concrete contact primer comes to the rescue.


The adhesion between two different types of materials is often a serious problem in finishing.. Primers such as concrete contact increase adhesion, even if the substrate does not absorb moisture well. The composition of such materials includes sand, cement and some special additives (they are determined by the recipe of the mixture). The rough outer layer of the contact primer is formed by sand and the cement helps it adhere better to the surface.

In production, only environmentally friendly materials are invariably used that do not emit bad smells and do not spoil the appearance of the walls.

Application and characteristics

You can use the material once after shaking.. It is recommended to use it to:

  • prevent paint degradation on dry plaster;
  • facilitate plastering;
  • improve the adhesion of tiles to concrete walls;
  • close seams and cracks;
  • reduce premature shedding of finishing materials.

The Knauf brand primer contains acrylic, which makes it highly resistant to moisture. At the same time, the quality of surface preparation is not worse than that of most other auxiliary materials (and sometimes even better).

Issued by:

  • both a universal mixture and adapted directly for interior work;
  • both coarse and fine.

Carefully thought out formulation and production technology allows the primer to remain unharmed for many decades.

After applying on the wall, it is enough to wait a few hours, and then immediately proceed to the main surface finishing.

The German concrete contact is colored pink. It is designed to impregnate substrates that are not able to absorb glue or leveling compound. The polymer dispersion composition helps even in cases where the previous finish is not dismantled, but overlapped.

The concrete contact is suitable for lubrication:

  • tile tiles;
  • expanded polystyrene;
  • drywall.

The leveling mortar, placed on the primer, dries evenly. Thanks to pre-treatment, it will be possible to reduce the amount of plaster or paint used. Concrete contact has antiseptic properties. It effectively suppresses the emergence of foci of any pathological microflora. When using it, the permeability of the intermediate layers of finishing increases, and because of this, ventilation of the premises, their exchange of air with the outside world is facilitated.

Knauf has a neutral acid-base balance. It retains its positive characteristics even in freezing temperatures of -40 degrees, and in temperatures up to +60 degrees.. Due to the absence of toxic components, Knauf concrete contact can be used even where ventilation is unsatisfactory – there will be no harm to the health of household members.

In a container of the most practical capacity (5 or 20 kg), the primer retains its characteristics for up to 1.5 years, unless the tightness is broken.

More about primer concrete contact Knauf – in the next video.

Consumption of the mixture

The consumption of high-quality concrete contact Knauf per 1 m2 is a very important and urgent issue. Professionals, and even those who have worked with such compositions at least once, will say for sure that this indicator is determined by the type of surface, its initial state and the level of moisture absorption..

When analyzing construction practice (on average), the following figures were obtained:

  • Consumption for brick, sand concrete and porous concrete is 500 g per 1 sq. M. You can reduce costs if you use impregnations that deeply penetrate the material.
  • First-class cast-in-place concretes are primed in the amount of 350 g per 1 sq m, provided that the pore size is medium.
  • When there are few pores or the surface is already covered with paint, you can spend only 150-250 g of primer to cover 1 sq m.

In order to fully ensure adhesion, the condition of the original wall surface must also be taken into account. If in the process of work gaps are found or the base very greedily absorbs the finishing material, you can cover it again, but only after the initial mixture has dried completely.

Determining exactly how much primer will have to be spent is not so difficult. Its small volume is weighed in a pallet and distributed over an area of ​​1 sq m on walls and ceilings.

Such a test facilitates the calculation, allowing you to avoid both the purchase of unnecessary material and its sudden end in the midst of work..

Home craftsmen and even experienced professionals are naturally interested in whether it is possible to deviate from the recommended numbers, to use a smaller amount of concrete contact. As practice shows, this is a big mistake: the cost of buying a primer is relatively small, and its lack worsens the quality of preparation. The created layer will be fragile – it can crack and delaminate. The worst thing is that later it will not be possible to achieve a normal level of adhesion with the main finish..

It is extremely important to take into account the peculiarities of drying individual materials.. If the sand concrete is dried at the wrong temperature and not moistened, the wall will dry out. Then even the best primer will not be able to prevent plaster shedding or cracks in the paint. We’ll have to redo all the work, re-invest in the purchase of finishing and preparatory materials.

The conclusion is simple: only strict adherence to the manufacturer’s instructions helps to avoid cost overruns..

At first, concrete contact can be mixed with deeply penetrating mixtures, and then it is permissible to use it only in its pure form.. When using a spray gun, the total consumption of primer increases slightly. The manufacturer recommends waiting for drying for 12 hours (this time is the maximum). If the temperature and humidity conditions are favorable, you can wait only 3-4 hours. When using hand tools, the concrete contact should not be diluted with water, but if it is sprayed mechanically, the solution is made in a 2: 1 ratio.

You can learn how to prime the walls before painting with your own hands by watching the video below..

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