Preparation of walls for decorative plaster. Rules for applying a primer for decorative plaster Requirements for puttying

Decorative plaster is a modern way to protect and decorate buildings, however, at the same time it is a very responsible job. If the material is applied with high quality, then the appearance of the house will be attractive, in addition, the consumption of the composition will be minimal, and its durability will be maximum. In order for the mortar to adhere very firmly and efficiently to the surface, before applying decorative plaster, it is necessary to use a special primer that is processed by the building. Experts in the field of construction and finishing say that a primer for decorative plaster must be applied, moreover, it must be applied correctly, in accordance with the technology.

Service life extension

In order for the plaster layer to have a maximum service life, it is necessary:

qualitatively level the surface vertically and horizontally;
apply the finishing type of putty to close up all cracks and irregularities;
apply a special primer to the surface of the walls, thanks to which the decorative finish will hold well;
make the base surface strong enough for further finishing work.

To perform all of the above work, you first need to find out what materials the building was built from and assess the technical condition of the walls. For example, if the base is porous, made of brick, concrete or wood, and also if it is an internal surface, then it must be treated with a deep penetration primer. This composition allows the surface to be vapor-permeable, and at the same time, the finishing material adheres well to the base coat. To perform external facade finishing works, completely different types of soil are used.
It is advisable to purchase primers containing antiseptic additives, due to which mold and fungi will not appear on the surface of a building finished with plaster.
If the walls are loose, then primer compositions with a strengthening effect are used. Thanks to them, the density will be significantly increased, the adhesive characteristics will increase significantly. These types of soil can even be used for application to the lime layer, because if this is not done, then after a few years the finishing material will begin to collapse.

alignment

Before carrying out finishing work, the area must be leveled. This can be done in various ways, but the method of hanging is considered the most effective and efficient. First, the section is marked diagonally with dowels, then a measuring thread is pulled between the driven dowels. Then, along this thread, you can see where you need to level the surface and how much.
Before plastering, you can even out the gaps with putty. When it is completely dry, it must be primed. If there are large protrusions and excess mortar, they can be knocked down with a hammer or chisel. Thanks to high-quality and scrupulous leveling, the consumption of expensive decorative plaster will be significantly reduced.
In the event that the surface is very uneven, when the gaps are 4-5 centimeters or more, then experts recommend leveling not by plastering, but by other methods:

creating a smooth metal frame;
upholstered walls with wooden shingles.

The metal frame, of course, significantly increases the bearing capacity of the wall area, but it is used less frequently than wooden shingles. Why? Because the metal is much more expensive, besides, it needs to be coated with an anti-corrosion compound to extend the service life.

Primer selection

The primer applied under decorative plaster can be divided into several categories:

alkaline, acidic or neutral;
various indicators of adhesive properties;
different viscosity of the composition;
suitable for a certain type of plastering.

If there are many external defects on the walls, such as rust spots, salt deposits, and others, then you need to purchase a primer with a high alkaline composition, the pH of which is 8 or more, to hide these defects, you need to use a deep penetration primer. This mixture will neutralize any salts, even very deep ones. Rust must be removed, as it reduces the adhesion index, destroys the wall and primer, if the mixture is not selected correctly.
Soils with a low pH value are suitable for application inside a building where the air humidity is low. In this case, the soil consumption will be much less than outside the house.

Puttying

When the walls are plastered, they must be puttied, whether it be external or internal surfaces. It is necessary to select putty depending on the type of plaster or the type of building materials used to build the building.
In order for decorative plaster to be durable and hold tight, you need to choose the right primer mixture, otherwise the plaster layer will completely or partially peel off. To prevent this from happening, it is necessary not to use putty, consisting of highly viscous substances, as well as those that do not absorb moisture well, for example, you should not use oil putty, glue, as well as primers based on alabaster.

Proper priming

Before applying a layer of decorative coating, the following conditions must be met:

prime the area at least twice, the thickness of the layers should be approximately 1 centimeter, or more. If primed with a thin layer, then such protection will be insufficient, it will not hold heavy plaster on the wall well. Naturally, the thicker the layer, the greater the material consumption;
The primer can be applied either with a wide brush or with a roller. You should not use narrow brushes, because the soil layer will lie unevenly, and it will be difficult to maintain the same thickness. Also, experts do not recommend using a spray gun, a vacuum cleaner or an airbrush, because due to the use of these devices, the quality of the coating will suffer, soil consumption will increase. In addition, deep penetration soils will not be able to penetrate deep enough into the walls if spraying devices are used. The consequence of this will be the delamination of the decorative coating some time after application;
upon completion of priming, it is necessary to wipe the treated areas. This operation must be performed for external and internal work. Thanks to grouting, the soil layer is significantly compacted, this will enable the decorative coating to adhere well to the surface;
the soil should not be allowed to dry out, so it is periodically moistened before plastering. This can be done with ordinary water, which can be applied with a spray bottle. Decorative types of plaster are much better and easier to lay on slightly damp walls. It is very important to do this, especially for interior walls.

Decorative plastering of surfaces is a very responsible way of finishing walls. Not only the appearance of the wall, but also the consumption per 1 m² of surface and the durability of the composition applied to it will depend on the quality of applying such plaster. To ensure the required quality of adhesion of the working solution to the coating base, before starting work, it is necessary to use various types of primers for decorative plaster, as well as the right technologies for their practical application.

For high-quality wall covering with decorative plaster, you need:

Carefully level the surfaces both vertically and horizontally.
Use finishing putty to seal all irregularities.
Ensure good adhesion of decorative plaster to the base.
Ensure the strength of the original surface, on which further work will be carried out.

To solve these problems, you need to know what material the walls are made of and what is its technical condition at the time of priming. For example, for continuous porous coatings (concrete, brick, wood) of internal surfaces, deep penetration primers must be used. It is they who provide the vapor permeability of the treated areas and good adhesion of the plaster to the base.

In addition, deep penetration primers often contain antiseptic components that prevent the formation of fungi and mold, which are almost impossible to remove from internal walls finished with decorative plaster.

In the case of loose surfaces, primers with a strengthening effect are used. They help to increase the density of the walls and, like deep penetration primers, improve adhesion performance. Such primers are recommended for use on lime plaster, since after several years of operation it begins to destroy the original surface of the wall.

Leveling the surface before work is carried out by several methods, but the most practical and giving stable results is the hanging method. The part of the wall to be decoratively plastered is marked diagonally with dowels, after which a measuring cord is pulled between them using a plumb line. By the sag of the cord, they judge where and how to level the wall.

The size of the gap before plastering can be partially eliminated with putty, after which the surface is primed. Surplus can be knocked down with a chisel or scraper. The primer consumption per 1 m² will increase, but the need for more expensive decorative plaster will decrease.

It happens that the gap is too large and exceeds 40-50 mm. In such cases, leveling and subsequent priming of the wall will not give the desired result. There are two options - before processing:

to upholster the surface with shingles;
arrange a metal frame.

The latter, although it increases the bearing capacity of decorative plaster, is used much less frequently in practice. The reason is considered to be increased costs, as well as the need to use steels with an anti-corrosion coating or an aluminum strip.

Priming compositions for decorative plaster are classified:

in terms of acidity pH: acidic, alkaline and neutral;
according to the degree of increase in the adhesion characteristics of the primed surface;
by the viscosity of the composition;
if possible, work with certain types of decorative plaster.

The first indicator is important for the ability of the primer to hide or, conversely, highlight the characteristic surface defects on the wall. These include rust spots and salt deposits, which are especially common after lime treatment of exterior walls.

With a significant number of such surface defects, it is necessary to use only alkaline primers, the pH of which is the highest (from 8 units or more), moreover, deep penetration compositions. In this case, when priming, salts are neutralized, as a result of which even deep spots disappear.

The same goes for surface rust. It most negatively affects adhesion, since it destroys not only the surface of the wall, but also the primer itself, if it is chosen incorrectly.

A primer with reduced pH values is suitable for interior wall surfaces in rooms with normal or even slightly reduced relative humidity. For such premises, the specific consumption of primer per 1 m² is reduced.

After plastering, any internal and external surfaces are puttied. The composition of the putty is also selected according to the degree of its affinity with the plaster material.

An important parameter that determines the durability of decorative plaster is the compliance with the chosen primer. Otherwise, after priming, partial or complete peeling of the plaster composition may occur. In order not to run into such a nuisance, it is necessary to exclude the use of putty, which includes highly viscous substances with little absorbency (for example, oil putties, putties based on alabaster, adhesives).

Features of priming walls for applying decorative plaster are as follows:

An exceptionally deep, two-layer priming is used, and the thickness of each layer must be at least 10 mm. A thinner layer will not hold heavy material on the wall. At the same time, the consumption of the composition per 1 m² will increase.
As a working tool, you need to use a wide paint brush or roller: the use of thin brushes will not provide the primer layer with the necessary uniformity and thickness. It is not necessary to use a vacuum cleaner, spray gun or spray gun for the purpose of imaginary acceleration of work: the primer consumption per m² will increase, but the quality of the coating will deteriorate. This is due to the fact that for a deep penetration primer, it will not be possible for the components to penetrate deep into the treated surface. As a result, decorative plaster after application will begin to flake off the treated surface.
After priming, the treated surface is immediately grouted. This operation is performed for both internal and external walls. As a result, the layer is compacted, providing a good basis for decorative plaster in the future.
So that the primed surface does not dry out, it must be moistened during the entire time before plastering. A regular flower trimmer or spray gun will do. The reason is that decorative plaster is easier and better to lay on a slightly damp surface. This is especially important for interior surfaces in residential areas.

The primer for work before applying decorative plaster provides the finish surface with the required durability. Its consumption per 1 m² is about 200 ml and depends on the wall material and the condition of the original coating.

Preparing the walls for decorative plaster is an important point, because the final result will depend on the quality of the preparation of the base. Today we will tell you how to prepare the walls for decorative plaster and at the same time provide for everything. Also on the video in this article and the photo you can see the individual moments of the work and this will help to carry out the work correctly.

Preparing the wall for plaster is done in a certain order. Everything is time-tested. It must be remembered that the application of plaster is the stage that completes the finishing work. Plastering is started after all windows and doors are in place, the flooring is fully laid (see Floor tiling with ceramic tiles - correct cladding).

Surface preparation is carried out in the following sequence:

First, the surface to be trimmed must be cleaned of the old layer of putty and paint., remove the remnants of the old wallpaper;
Next, the surface of the wall is treated with a special primer mixture., which performs a restorative and strengthening function;
If the humidity in the room is very high, then along with priming, it is necessary to additionally treat the walls with an agent that has an antifungal effect;
If there are cracks in the walls, then they are embroidered and filled with a special composition for repair. Very large cracks are filled with a repair compound in several approaches;
Only after complete priming of the walls should a putty layer be applied to them., which completes the stage of their alignment and is the basis for finishing the surface with a decorative plaster coating.

Attention: If in the future it is planned to apply a thick layer of plaster coating with a clearly defined structure, then wall putty is not necessary in this case.

If the decorative coating will be applied in a thin layer, then the preparation should include all stages without exception. Otherwise, it will not be possible to hide all the errors of the base under the decorative layer. This will also lead to an increase in the consumption of finishing material.

When all puttying work is completed, you can start sanding the surfaces of the walls (see How to sand the walls after puttying and how to do it right), using fine sandpaper for this.

Wall surface priming

Preparation of walls for decorative plaster is done on a primer. It significantly enhances the adhesion of surfaces and ensures the durability of the coating. Here everything is done by hand and therefore the price of the work will be reduced to the cost of the material.

Attention: This stage is very important, because a good primer mixture can save the repair for a long period of time. In this case, you can not be afraid that the plaster will crumble.

The primer for plastering is an opaque liquid that does not have a characteristic odor, priming is the work of applying and distributing the primer over the surface of the treated area. After drying, it becomes like a film, which provides a strengthening of the surface, and an improvement in the setting of the plaster.
The primer penetrates into the depth of the wall, improving its adhesive properties and preventing metal corrosion. Waterproof film prevents the penetration of moisture, provides protection against bacteria, preventing the formation of mold and rot on the drywall surface. Under it, you can hide small spots and traces of streaks. Applying a primer mixture in several layers enhances the properties of the composition.
It is desirable to buy a mixture of high quality and deep penetration, this will reduce the cost of finishing materials. It is good if the brand of the primer matches the brand of the plaster mix. Each manufacturer manufactures its products in whole lines, where all components fit perfectly together.

What soil to choose

Preparing the walls for plastering the video will show you the entire progress of the work. But the soil must also be chosen correctly. According to the structure of the coating. Today, on the shelves of hardware stores you can find a huge range of primer mixtures. In order to make the right choice, you need to know which primer is suitable for certain surfaces.

The alkyd primer is perfectly applied to the untreated wood, leveling its structure and creating a smooth surface for plastering. The advantages of this mixture include quick drying. You can use a polystyrene primer, it can also be applied to plastered surfaces. But it should be noted that it contains substances that are harmful to health.
For metal surfaces, a primer is used, which is produced specifically, based on the type of metal. Usually these are mixtures with zinc additives. It is possible to use an alkyd primer mixture with zinc additions, which provides anti-corrosion protection. The use of glyphthalene mixture is difficult because it has a long drying period.
The use of perchlorovinyl primer mixture is recommended for concrete and brick surfaces. It dries quickly, but has a pungent odor. Therefore, it is better to work with open windows.
Acrylic and emulsion primers can be applied to any surface. They are practically odorless, and their drying period is 5 hours. Acrylic primer can even be applied to the old layer of plaster, thanks to its composition, it provides its strengthening. Also, the acrylic mix is \u200b\u200bperfect for drywall surfaces.

The method of applying the primer mixture

The technology of preparing walls for plastering includes high-quality ground application. Having bought all the necessary materials, you can start priming the walls before plastering them. It is worth noting that primers are sold in three different states: dry, concentrated and diluted.

Diluted mixtures can be used immediately. Before starting work, the diluted primer is thoroughly mixed so that the entire sediment rises from the bottom and is distributed throughout the entire volume of the mixture.
Dry and concentrated mixtures are first diluted according to the proportions recommended in the instructions.
Before starting work on priming, you need to clean the surface of the walls. Grease and oil stains should be removed, all dust and dirt should be wiped off.
To avoid getting the mixture on the painted areas, they must be sealed with a special film or tape. The primer leaves glossy spots on the paint.
On drywall surfaces, it is necessary to seal the joints with a special mesh. Work should only be done with gloves, because these mixtures have a detrimental effect on the skin and are not easily washed off.
Now consider the priming technique itself.

Preparation for plastering walls with a primer includes the presence of a certain tool and the following equipment will be needed to complete the work: a brush for areas with difficult access, rollers with a long and short handle, a container for soil and the primer mixture itself.

First you need to use a long-handled roller to apply the mixture to easily accessible sections of the wall. Next, with a smaller roller, evenly distribute the primer, moving it up, down and in both directions.
Then you can move on to hard-to-reach places, corners and joints. To do this, you need to use a construction brush. Once you have finished applying the primer, let it dry. Drying time is indicated in the instructions for the solution.

Attention: Preparing the walls for plastering the video will show the rules of work, but if the plane is large, then it is better to purchase a spray gun for work, this will greatly speed up the work and you will be able to make a uniform coating.

Don't limit yourself to just one coat of primer. To enhance its properties, it is necessary to re-apply the mixture. You need to carefully examine the surface of the walls, so as not to miss even a small area. As soon as the second layer of the primer mixture dries, you can start plastering the walls.

When preparing walls for plastering, it is necessary to take into account a number of important points that affect the quality of the work performed:

All applied putty layers must be thoroughly dried. Drying time should not be less than 2 days;
to prevent the formation of cracks, you can use a special self-adhesive mesh. In another way, it is called "serpyanka";
after the putty layer has dried, it is recommended to prime all wall surfaces with an acrylic primer mixture, due to penetration far into the wall, ensuring good interaction with the decorative coating;
it is possible to increase the strength of the primer and protect it from separation into layers by using a special impregnation. It should be noted that the selected putty mixture must have good absorbent properties. Oil and alabaster bases are not allowed.

When applying a primer mixture for decorative plastering, you should use the advice of specialists:

The primer layer is applied to the surface of the wall with a thickness of about 2 centimeters, its smaller thickness will not allow to obtain a decorative coating of uniform composition and high quality;
When rubbing the primer layer, it is imperative to carry out measures to compact it.;
After completing the priming work, it is necessary to moisten the treated surface periodically.. This should go on for a week. Moisturize with a sponge dampened with water.
After carrying out all the above procedures, decorative plaster can be applied to the treated surface.

Decorative Coating Testing

After completing the preparatory work, it is necessary to apply a test layer of decorative plaster. This is necessary to check the readiness of the wall surface.

To do this, choose a small section of the wall, located next to the corner of the room, and apply a layer of plaster. This will make it possible to see what quality the decorative coating will be, its structure and color scheme.
Particular care must be taken to ensure that the transitions between smooth to textured surfaces of the coating are sufficiently smooth.
Also, if you use stamps, then immediately check the embossing, it should be of high quality.

You now know how to prepare a wall for plastering, and the preparation of walls for decorative plastering video and the above instructions will not allow you to make mistakes when doing work.

One of the ways to decorate the walls in the house in an original way is to use decorative plaster. It is her who is considered by many to be an excellent alternative to wallpaper or tiles. Like any type of final finish, decorative plastering requires a primer to be applied to the surface first. In this case, it is even more important: a quality primer is one of the most important components of success. The use of a special primer is due to the characteristics of the coating: decorative plaster requires good adhesion. In addition, it is important that the surface is not dusty, and the coating falls on it evenly.

Important parameters

Before you buy a primer for decorative plaster, you need to understand what kind of composition you need. The mixtures available on the market are different:

by pH balance. This parameter is especially important when coating defective surfaces. For damaged walls, where rust stains or lime deposits are visible, and in damp rooms, primers with the highest pH should be used. If there is no damage, and the humidity is low, you can buy a decorative primer with a lower pH for processing;
level of adhesion and viscosity. It all depends on what characteristics the plaster itself requires;
compatibility with various materials. This parameter determines if the primer you have chosen is compatible with other compounds you have purchased for the repair.

Features of working with the material

Features of priming surfaces for decorative plaster are quite specific. So, plaster is best laid on a damp surface, so you should not wait for the soil to dry. It is best to moisten it little by little if you notice that the coating is starting to dry. It is necessary to prime in two layers and deeply, otherwise heavy plaster will simply crumble from the walls, so it is advisable to use deep penetration compounds. For better plastering, the primed surface must be rubbed - so the layer will become more dense and smooth.

The price of a decorative primer depends on its composition, quality and brand. You can buy a suitable product in our store. To do this, contact us by phone or through the order form, and we will help you purchase the product that you need.

Long term coverage conditions

For high-quality wall covering with decorative plaster, you need:

Carefully level the surfaces both vertically and horizontally.
Use finishing putty to seal all irregularities.
Ensure good adhesion of decorative plaster to the base.
Ensure the strength of the original surface, on which further work will be carried out.

Pre-alignment is an important point

It happens that the gap is too large and exceeds 40-50 mm. In such cases, leveling and subsequent priming of the wall will not give the desired result. There are two options - before processing:

to upholster the surface with shingles;
arrange a metal frame.

Features of the choice of primer

Priming compositions for decorative plaster are classified:

in terms of acidity pH: acidic, alkaline and neutral;
according to the degree of increase in the adhesion characteristics of the primed surface;
by the viscosity of the composition;
if possible, work with certain types of decorative plaster.

The same goes for surface rust. It most negatively affects adhesion, since it destroys not only the surface of the wall, but also the primer itself, if it is chosen incorrectly.

A primer with reduced pH values is suitable for interior wall surfaces in rooms with normal or even slightly reduced relative humidity. For such premises, the specific consumption of primer per 1 m² is reduced.

Putty requirements

After plastering, any internal and external surfaces are puttied. The composition of the putty is also selected according to the degree of its affinity with the plaster material.

Priming technology

Features of priming walls for applying decorative plaster are as follows:

An exceptionally deep, two-layer priming is used, and the thickness of each layer must be at least 10 mm. A thinner layer will not hold heavy material on the wall. At the same time, the consumption of the composition per 1 m² will increase.
As a working tool, you need to use a wide paint brush or roller: the use of thin brushes will not provide the primer layer with the necessary uniformity and thickness. It is not necessary to use a vacuum cleaner, spray gun or spray gun for the purpose of imaginary acceleration of work: the primer consumption per m² will increase, but the quality of the coating will deteriorate. This is due to the fact that for a deep penetration primer, it will not be possible for the components to penetrate deep into the treated surface. As a result, decorative plaster after application will begin to flake off the treated surface.
After priming, the treated surface is immediately grouted. This operation is performed for both internal and external walls. As a result, the layer is compacted, providing a good basis for decorative plaster in the future.
So that the primed surface does not dry out, it must be moistened during the entire time before plastering. A regular flower trimmer or spray gun will do. The reason is that decorative plaster is easier and better to lay on a slightly damp surface. This is especially important for interior surfaces in residential areas.

Categories

Popular