Glue wallpaper without a primer. Is it necessary to prime the walls before wallpapering? Why prime the walls

Primer for walls under wallpaper is available in retail, and they themselves make it quite often. But many are wondering if it is necessary to prime the walls before wallpapering, and if so, then how to prime the walls before wallpapering.
This topic will be the focus of our article. You will be able to see photos and videos on this topic and do the job correctly.

Before you decide whether you need to prime the wall before wallpapering, let's figure out why you need to prime the walls before wallpapering. After that, you can decide whether it is necessary to prime the walls before wallpapering in your case.

If you are not sure that you can correctly assess what kind of work is required in your case, you can invite the master. He will draw up a work plan, outline them and complete them in a short time.

Whether it is necessary to prime the walls before wallpapering is probably always decided by the room itself. If this is a millet utility room and almost no one is there, then it is quite possible to think why the walls should be primed before wallpapering.
But this is far from correct. After all, the wall is part of the frame of the house and the fungus can then expand throughout the structure.
So:

The primed wall is made even and dry, the primer increases the reliability of the adhesion of the adhesive to the surface. A good primer ensures that the bottom layer remains intact and does not crack, in addition, it will not allow moisture to soak into the walls.
The primer applied to the wall allows it to "breathe", thereby creating a good microclimate, and preventing the fungus from spreading. Do not think that the wallpaper will stick well on the wall without a primer, this is a huge misconception.
Wall primer strengthens the outside of the wall and penetrates the inside. It simply fills the cracks and pores of the surface. It enhances the bonding of surfaces and prolongs the life of the wallpaper (see Wall decoration with wallpaper in the correct design). This is one of the main parameters why a primer is made for wallpaper.

Training

Now we will figure out how to properly prime the walls before wallpapering. Like any job, this one requires preparation. From this will be in many respects the envy of longevity.
So let's take a look at how to prime the walls for wallpaper:

Wall priming is carried out after all the initial stages of work, including the removal of nails and old plaster.
The primer is applied after applying the putty, which has had time to dry.
The primer for walls under wallpaper begins with the fact that the wall is moistened with a special impregnation. This is necessary in order to wash off the dirt and dust that remains after a rough surface treatment, because wallpaper cannot be glued to a dirty wall.
Everyone knows that newspapers were first glued to the wall and wallpaper was already on them, but now the primer has forever replaced printed materials.
After the primer dries, the wall does not get dirty and becomes stronger than before. Thus, the wallpaper lays flat on the wall and holds firmly and for a very long time.
If you got a wall that was previously covered with wallpaper, you need to remove them and wash off the glue. This is done with a metal spatula or scraper and water.

Attention: If the wallpaper does not absorb moisture well and does not lag behind the wall well, then cuts should be made on the wallpaper for better moisture penetration. These days, stores sell a special liquid that quickly removes wallpaper.
This liquid is added to a bucket of water, and wet the wall, leaving it soaked for half an hour. After half an hour, wet the wall again and easily remove the old wallpaper from the wall.

When the wallpaper is removed, it is necessary to properly wash the wall with warm water and clean the surface of the wall with a wide spatula from glue and whitewash.
Often in rooms with high humidity, such as a kitchen or bathroom, mold collects in the corners. This mold must be removed so that it does not appear on the newly repaired wall.
Places where mold has settled should be treated with bleach. As a rule, 200 grams of lime are required per liter of water. It should be noted that when pasting places where there was mold, glue must be bought with a fungicide content.
After removing old wallpaper, glue and mold, it is necessary to meticulously inspect the surface of the walls. Found cracks and irregularities must be puttied. If your apartment is not warm enough, you can make it warmer with a thin layer of Styrofoam. This method will not only make the apartment warmer, but also hide wall defects.
Before you prime the ceiling, you need to get rid of the hook, holes and cracks properly by filling them. If the ceiling consists of drywall, gypsum or other porous surface, then it must be primed in any case.

Primer work

Now we decide how to prime the walls before wallpapering. There are many materials in retail.
Some do it just with pva glue. The walls are also primed before wallpapering with the glue that will be used when gluing the material itself, for this it is simply made more liquid.

Dilution of the primer

Therefore, it is up to you to decide how to prime the walls under the wallpaper. Just before that, the instructions for using the primer should be carefully studied, it can simply be for different surfaces. Although all of it is applied and completely with your own hands.
So:

The primer composition is best diluted in a bucket. The primer is different and before diluting it, you need to read the instructions that are written on the package.
Stir the mixture well so that there are no lumps left. To stir the solution, you can use a drill with a mixer nozzle, in this case a very good composition is obtained. Manually, this quality of the composition is difficult to achieve.
The primer is applied with a wide brush. This is very similar to whitewashing the ceiling (see Ceiling lining: types of material). Having spread an even layer of the composition on the wall, avoiding irregularities and untreated areas.
After you have primed the wall for the first time, you need to give it time to dry. Drying time is usually written on the package. Even if by your standards the surface of the wall after the first primer looks perfect, you still need a second coat of primer.
A lot depends on the quality of the wall on which the primer is applied, which can be impregnated differently on the same wall. When re-priming, the quality will be excellent and there will be no differences. On a completely flat wall, you can work with a paint roller, it is much more convenient and smoother than working with a brush.

Soil types

Before deciding how to prime walls for wallpaper, let's just look at a couple of types of mixtures most commonly used for priming a surface.

acrylic primer

This type of primer is able to work with putty, plaster and concrete. Acrylic primer always does its job.

Attention: If the wall surface is poorly treated, then a "deep penetration" primer will work just fine, but a regular primer does its job well too.

So:

The primer for wallpaper should be of good quality, and in order to avoid trouble, you should buy a primer from well-known companies. You should not look at the inscription "for wallpaper", as this is nothing more than a marketing ploy.
In the store you can still find a substance called “wallpaper primer”, which is actually just diluted PVA glue. But you need to know that this composition is several times more expensive than the PVA glue itself.

Attention: Before buying an acrylic primer, be careful and see what would be written on the package that the primer consists of a mixture of acrylic polymers, and not PVA glue.

Acrylic primer per square meter will need 100-200 milliliters. This may depend on how porous the wall is.
The primer is applied with a paint roller, but if there are hard-to-reach places, then for this it is worth working with a wide brush. The primer should dry for about three hours, after which you can start wallpapering.

Primed walls with wallpaper paste

Many are familiar with the option of priming the walls directly with wallpaper glue. Only with this option you should not rush. You need to know that not just any glue, but only a few brands of wallpaper glue is suitable for priming walls before wallpapering.
So:

If the adhesive is intended for priming walls, then this must be written on the package.
On the same package, it should be written how to dilute the glue in order to use it as a primer. If you did not see such an inscription, then this glue is intended only for wallpapering. Maybe this option is suitable in some cases, but still it cannot be compared with an acrylic primer, because working with it is much easier and more pleasant.

Thus, we can safely say that you should not save on a primer for your home and you should not “reinvent the wheel”, because acrylic putty has already been invented and will make your home better. Although it is up to you to decide whether it is up to you to prime the walls before wallpapering.

Tsugunov Anton Valerievich

Reading time: 3 minutes

Repair always requires a lot of time, effort and decision-making, on which the result will depend in the future. One of the main tasks during the repair is the decoration of the walls: if everything is carefully thought out, the room will look perfect and please the eye for a long time. Wallpapering a room is one of the easiest and most convenient ways, but some questions may arise here, in particular, whether it is necessary to prime the walls before wallpapering.

Do you need a primer on the walls?

And yet, do you need to prime the walls or can you save time and do without pre-treatment? In fact, in theory this is possible, but in practice it is better not to skip this stage, because the result suffers because of this. And especially its durability, because if you do not prepare the walls, then after a while the wallpaper can literally slide off them. It happens that the material begins to bristle and peel off the very next day after the repair work.

The cause of the problems is too low adhesion. Small cracks and voids do not allow the wallpaper to stick well, and no matter how much glue is used and what quality it is, they will not stick very well. Therefore, it is necessary to prepare the walls in advance and create the most convenient conditions for work.

When applying a primer, its composition penetrates the surface of the wall and fills all the pores and voids, thereby increasing adhesion, so the wallpaper sticks better.

Work on a flat and smooth surface is much easier, and the appearance of the finish coat looks better with a primer mixture than without it.

Advantages of priming

In addition to making the wallpaper stick better and look more attractive due to the primer, there are a number of other advantages of wall pretreatment:

The primer mixture strengthens the surface layer of plaster and putty, thereby preventing its premature destruction, the appearance of all kinds of defects and chips. This is especially important if the wall will be covered with wallpaper.
If the surface is not primed, then for high-quality gluing of wallpaper, you will have to spend a lot of wallpaper glue, and preferably of high quality. It turns out that if you simply use the soil, the costs will be much lower.
Many primers contain antiseptic agents that help protect walls from mold and other fungal growths.
The wall will not absorb unnecessary moisture from adhesives.
The primer allows you to even out the color, this is especially necessary when pasting a room with thin wallpaper. If you first apply a primer, then after that you don’t have to worry that the surface may acquire an ugly yellow or gray tint. In addition, the composition will hide stains on the walls and streaks.
Wallpapering primed walls is much easier. Sometimes the material does not want to stick to the surface in any way or begins to fall off if priming is not done first. Without a primer, the glue on the wall dries quickly, and you have to apply it to the wallpaper again, because of which they get wet and tear. Much easier to prime the wall in advance. By preparing the surface, you can save time, effort and nerves.
Priming is a guarantee that the glue will be distributed evenly and there will be no dry spots on the wallpaper.

Primer selection

In the store it can be difficult to choose the necessary material, since the choice should be made individually. As for brands, for the best result, it is certainly better to give preference to well-known and proven companies.

Some manufacturers, under the guise of a primer, sell diluted PVA glue, which, although it can be used for priming, is inferior in efficiency to specialized primers. In addition, PVA sold in cans labeled "primer" is unreasonably expensive.

Alkyd primer is suitable for treating wooden surfaces before applying any type of cladding to it, from paint to wallpaper. It is quite easy to use, the applied composition dries completely after 15 hours. But there is one caveat: such a composition cannot be applied over plaster, especially one that is based on gypsum, as well as on drywall.

Glyphthalic primer mixture has proven itself well when working with metal and wooden surfaces. Unlike an alkyd primer, this type can be applied to both plaster and putty, the main condition is that the room is not too humid. This coating dries for about a day.

Acrylic primer is best suited for processing walls under wallpaper. This composition does not smell of anything, it can be applied to any material except metal. It dries incredibly quickly, within 5 hours. Suitable for wall decoration made of brick, wood, plywood and cement.

Acrylic primer composition is of two types:

ordinary;

The first is a universal option for those who do not know which primer to choose. Such soil looks cloudy, almost colorless.

The deep penetration primer lives up to its name - it penetrates deep into the surface to be coated, strengthening it. Such a composition is absolutely necessary if you are going to paste over an unprepared wall without prior puttying.

Do not buy a primer that contains silicone. Wallpaper glue will not stick to it, and hence the wallpaper itself.

In preparation for priming and wallpapering walls, use the following tips.

Not everyone knows how many times to prime the walls. It is enough to apply a high-quality primer on a well-prepared surface once. On porous, heavily crumbling and moisture-absorbing substrates, primer should be applied in 2 layers.

Inexperienced finishers often ignore the process of properly preparing surfaces before wallpapering, believing that it is enough to eliminate irregularities, but in reality everything is more complicated.

It is easy to understand whether it is necessary to prime the walls before wallpapering, evaluating the advantages that this procedure brings:

walls treated with a primer do not support the spread of mold and mildew;
impregnation provides better adhesion - the wallpaper will stick firmly to the wall;
the treated surfaces have a higher moisture resistance, which also ensures a strong adhesion of the wallpaper to the wall even at high humidity;
the primer levels small irregularities of the wall and eliminates excessive porosity of the surface.

The listed useful properties of the primer make it possible to perform work on gluing walls with a higher quality, ensuring the durability of the coating, which is especially important when installing expensive products.

Types of primers and their characteristics

When choosing a certain type of primer, you should consider the material that is the basis of the product. Manufacturers have developed special formulations that are best used for heavy and light materials. The composition of the soil is divided into several types:

Acrylic. These impregnations are used for the treatment of concrete surfaces, drywall and wood. Great for living rooms, as they are odorless. The term of complete drying is up to 24 hours. Impregnations of this type are classified as universal.
Alkyd. Used to prepare wooden and metal surfaces for subsequent painting or pasting. Dries quickly enough - up to 12 hours. Cannot be used to protect plastered walls.
Glyphthalic. These impregnations are designed for metal products. It will take at least a day to dry.
Perchlorovinyl. Prohibited for application in living rooms. Designed for coating mineral substrates and metal products. Drying time - up to 4 hours.
Polyvinyl acetate. For high-quality impregnation under standard conditions, 30 minutes is enough. It is used to cover walls before gluing with PVA-based products.
Polystyrene. Also not recommended for interior protection. Designed to protect wood and plaster walls.
Phenolic. Designed to protect wood and metal elements.

Which is better to use depending on the surface

The undeniable advantages of wall impregnation using a primer prove that a primer under the wallpaper is necessary to obtain high-quality pasting. Which impregnation to choose depends not only on the composition of the roll material, but also on the type of surface.

handle concrete surfaces are best with universal acrylic or alkyd impregnations. These solutions, getting into the structure of concrete, create a slightly rough coating, which provides excellent adhesion when sticking both paper and non-woven wallpaper.

If the owners decide to paste over the ceiling, then these types of primer should also be applied to the surface of the floor slabs. Proper processing will not only increase adhesion, but also give water-repellent properties to the surface. H

It is impossible to apply impregnation on concrete painted with water-based paint. To prepare such a wall, they clean off the old water-based emulsion, putty, level the base and only then treat it with a primer.

When to paste wooden walls, use primers for painting based on oil solutions. For processing plywood or fiberboard suitable acrylic primer.

For sheet materials (GVL, drywall, OSB), which are often used in new buildings, it is recommended to use universal acrylic solutions with an antiseptic. Such a base will be poorly impregnated due to the characteristics of the material, but vinyl wallpaper and glass wallpaper can be reliably placed on the treated surface.

When choosing a primer, you should first of all focus on the material from which the wallpaper itself is made. So, the primer for liquid wallpaper can be either acrylic or quartz. For paper products, it is enough to treat the base with a latex composition. A special vinyl acetate primer has been developed for vinyl products.

Necessary materials and tools

To prime the walls before wallpapering, it is recommended to acquire some material base. You will need:

primer suitable for the surface to be glued;
a container for preparing a solution;
a bath with a cuvette for rolling out a roller;
brush 150 mm;
a roller with a fur skin on the handle, 50-70 cm long;
damp cloth to remove primer smudges.

Use a stepladder or any other elevation, you only need when processing corners at the top of the wall, which must be processed with a brush. Applying a primer to the main surface is easy to do with a roller on a long handle directly from the floor. Using the listed tools, it will be easy to do the soil protection of the base with your own hands.

Preparation of a mixture for priming

The primer before wallpapering is prepared using the instructions that the manufacturer places on the package.

Primer in factory packaging is most often supplied ready-made and already prepared for use. Mix this mixture well enough. If necessary (for the treatment of reinforced concrete foundations), the walls are primed for wallpaper with less concentrated compositions, for this, acrylic primers are diluted with water, and alkyd primers with white spirit.

Concentrated primers are adjusted to the desired consistency according to the manufacturer's recommendations.

To dilute the dry concentrate, you will need a deep container, a mixer and the solvent provided for in the instructions. The powder is poured into water and brought to a homogeneous state; a properly prepared primer should not have lumps.

Flow calculation

Primer consumption is affected by many factors, so you should not rely solely on the value of the norm per square meter recommended by the manufacturer. Increases cost:

increased air temperature in the room;
surface structure (degree of porosity).

When calculating the required volume of material, the manufacturer's recommendations should be followed, but there are average primer consumption rates for various surfaces:

concrete surfaces - 350 g / m 2;
drywall, GVL, OSB and GKL sheets - 120 g / m 2;
plaster for painting - 100 g / m 2;
wooden surfaces, including plywood - 120 g / m 2;
metal surfaces - up to 120 g/m2.

The indicated standards are indicative indicators, but in the absence of accurate data, they can be used to determine the required amount of priming solution.

How to prime walls for wallpaper

Preparing the surface of the walls for pasting is quite simple. This task will be mastered by any beginner in construction, the main thing is to follow the recommended sequence of actions:

For successful treatment of walls with impregnation, it is recommended to ensure the temperature and humidity conditions in the room. Temperatures from +5 to +30°С, and humidity up to 75%, are allowed for work.
All tools are prepared before work begins.
Before priming, the walls should be cleaned of old wallpaper and paint. To do this, use a spatula and hot water. If the old coating is difficult to remove, you can use special solutions to remove wallpaper.
The cleaned surface is checked for cracks and irregularities, which are corrected with putty, followed by the application of leveling solutions.
In a bucket or other container, thoroughly mix (with a mixer or manually) ready-made solutions or prepare a primer according to the instructions. If it is planned to paste over the walls with wallpaper for painting, it is allowed to add appropriate pigment compositions to the soil, which will create a better base that does not contrast with the main color of the coating.
With the help of a brush, the finished solution is first treated with hard-to-reach places (corners, adjoining walls to the ceiling).
The main area is covered with a roller. For convenience, the primer is poured into a bath with a cuvette.
Re-treatment is possible after the final drying of the previous layer. For high-quality preparation for gluing, it is enough to process the surface twice.

How long does the primer dry

The drying period for different types of material is different and can vary from half an hour to a day. Many finishers prefer not to wait the due date and start work 20-30 minutes after applying the primer.

Such haste is not welcome, but in conditions where the room temperature is above + 25 ° C, the primer dries really quickly, which allows you to apply wallpaper paste without fear.

Under standard temperature and humidity conditions in the room, the drying times for different primers are as follows:

Acrylic - up to 8 hours.
Oil or contact - up to 24 hours.
Alkyd - up to 12 hours.
Special quick-drying - up to 7 hours.

It should be remembered that high temperature and low humidity reduce the drying time of the solution, and vice versa, in more humid conditions at temperatures below +16 ° C, the process of absorption and drying is slower.

How long can wallpaper be glued

In order to set the exact time frame for gluing the wallpaper after the primer, it is necessary to determine the drying time of the primed surface. Roll materials can be glued only after the last layer of the solution has been completely absorbed.

To ensure the completion of the polymerization process of the composition, it is imperative to wait at least a day after applying the finishing layer, this time is enough to calmly stick the wallpaper on the prepared walls of the apartment.

How to prime the walls before wallpapering? Is this operation required? Why is she needed? How to prime plaster, drywall and concrete? Let's try to answer these questions.

General concepts

First, let's find out what the surface for pasting should be.

durable. The universal rule of finishing work: the base should always be stronger than the coating. Otherwise, we will quickly get a delamination of the fine finish along the border between it and the base.
Moderately absorbent.

Let us clarify: both excessive hygroscopicity, leading to excess consumption of glue, and the complete absence of pores are equally harmful: in this case, reliable adhesion between the coating and the base will not be discussed in principle.

Relatively flat. Wallpaper will hide minor defects; but serious irregularities will still be noticeable. Note: matte, textured and contrasting wallpapers hide irregularities; glossy, smooth and monochrome - emphasize.
devoid of dust.

The role of the primer

Why prime the walls before wallpapering? What role does soil play in foundation preparation?

To answer this question, it is necessary to have a good understanding of the processes occurring, for example, in a layer of plaster after treatment with deep penetration soil.

The plaster is a grain of sand cemented with fairly large gaps; primer is an aqueous dispersion of acrylic resins.

Water, together with the smallest droplets of a binder - acrylates - penetrates into the pores of the plaster to a depth of 1-2 to 10-15 centimeters. The greater the amount of soil applied to the surface, the generally greater the penetration depth; hence the instruction to prime weak plaster at least twice.
When water evaporates during the drying of the soil, the smallest droplets of resin stick together into long chains leading deep into the plaster. As a result, a kind of three-dimensional web is formed, penetrating the base.

Result? Partially filled pores (namely, partially: the glue will be able to penetrate to a sufficient depth to ensure reliable adhesion to the base) and, most importantly, plaster particles reliably connected to each other: the polymer cobweb duplicates the binding role of cement. At the same time, the primer will reliably stick the dust remaining on the walls to their surface.

In addition: even a perfectly smooth surface coated with acrylate provides better adhesion to most adhesives. This feature is associated with the structure of the resulting polymer film itself.

Soil selection

So, what is the primer on the walls before wallpapering?

Acrylic Penetrating Primer

How this composition works - we have already found out. The price of a primer depends on its manufacturer, secondary additives and place of production: it is clear that the final consumer will pay for delivery from a remote region; on average, it is 50-100 rubles per liter.

Acrylic primers are the most versatile and are used not only for wallpaper:

They are used in order to ensure better adhesion of the putty to the base - drywall and concrete.
The primer for painting will greatly reduce the consumption of the dye.
Finally, acrylic dispersions with specific additives are often used as water repellents: they reduce the absorbent properties of walls and thereby prevent their accelerated destruction by water crystallizing in winter cold.

What should you pay attention to when choosing a primer?

The presence of fungicides (antiseptics) in its composition is welcome. These additives not only kill mold, but also prevent its occurrence in the future. However, antiseptics are sold in the form of water-soluble additives and can simply be mixed into soil that does not contain them.

Please note: if you are going to wallpaper a room in which a fungus has wound up, a primer on top of the plaster is not enough. Mold spores will remain underneath. The affected walls will have to be cleaned to concrete or masonry, treated with an antiseptic and re-plastered.

Hydrophobic compositions with the addition of silicone are absolutely not suitable for us. Why?

Counter question: have you ever tried to paint a seam sealed with silicone sealant? Silicone does not adhere to any dyes and adhesives; the wallpaper just fell off.

Wallpaper glue

How to prime the walls before sticking non-woven wallpaper? As you know, they differ from other types of wallpaper in that the glue is applied only to the wall.

If the plaster of the walls does not look loose, does not crack or crumble when you run your hand over it, you can use the same wallpaper paste for priming. It is diluted to a more liquid than usual consistency. Glue differs from specialized primers in that it only fills the pores and improves the adhesion of the wallpaper to the surface layer of the base; the mechanical properties of the wall change insignificantly.

PVA

If you are doing DIY repairs in a high humidity area, it is better to use PVA instead of traditional wallpaper adhesives. It favorably differs from them in the water resistance of the adhesive seam.

However: you can no longer remove the wallpaper after wetting it. It is better to glue thick vinyl on PVA: if necessary, you can remove the vinyl film itself from the walls; the glued backing peeled off from it will remain on the walls.

With the same PVA, only diluted with water to the consistency of milk, the walls are primed.

Technology

The priming process itself is ridiculously simple: all that is needed is to wet the walls once or twice with the composition of our choice. Tools can be a medium pile roller, brush or sprayer.

There are a few subtleties here:

Do not forget to pre-dust the walls with a whisk or vacuum cleaner.
It is better to wash the tool with water immediately after use.
The floor and furniture should be protected with polyethylene.

In the photo - a primer of a plasterboard wall.

Conclusion

As you can see, there are no special difficulties and secrets. Materials are common and inexpensive; the process of priming the walls is extremely simple and does not require rare tools.

As usual, more information can be found in the video in this article. Good luck!

Wallpaper among finishing materials has taken a height inaccessible to competitors. And there are many reasons for this:

a variety of types and types (paper tapestries, non-woven, glass, vinyl, liquid, etc.);
all kinds of design solutions;
a range of prices available for different categories of buyers, literally from cheap to very expensive, when one tube costs several thousand rubles;
simple gluing technology, which allows you to do the finishing yourself.

And it’s very disappointing when a work done by one’s own hands after a couple of years needs to be redone - the sheets began to fall off, dark spots appeared in some places, etc. The reason is not in bad glue and not in the lack of experience of home finishers. Just a primer was not applied to the surface of the walls before wallpapering.

Do I need to prime the wall before wallpapering?

Thousands of skeptics will object: "fathers and grandfathers did not know what a primer was, and the wallpaper hung on the walls for decades." In part they are right. Indeed, a few decades ago, if walls were primed, they did it either with very liquid home-made glue, or they used diluted PVA glue.

However, this statement ignores the fact that at that time the wallpaper was paper, and therefore light. Therefore, glue based on starch or flour easily kept them on the wall for a long time. In addition, the types of walls did not have a variety: brick, wooden, which were necessarily plastered with cement-sand mortar, and concrete. Their adhesion (adhesion) with the adhesive was good.

With the advent of new types of wallpaper (heavy, with different bases) and types of wall material (aerated concrete, gas silicate, etc.), as well as the start of using GKL (drywall), GVL (gypsum fiber sheets), OSB (oriented strand board) for dry plastering and plywood, it has become very difficult to achieve good adhesion of walls with wallpaper with glue. The primer for the walls under the wallpaper was able to solve the problem.

A primer (another name is “primer”) is a special liquid composition that is applied to the surface to be glued to create a reliable adhesion between the wall and the wallpaper adhesive. Do walls always need to be primed before wallpapering? Almost always. There are three exceptions when this type of work is inappropriate:

temporary repair, for four to five years;
bought light paper wallpaper;
pasting is done in the utility room.

In other situations, applying a primer allows:

improve adhesion between the wall and the adhesive mass;
bind dust microparticles that could not be removed during the preparation of the wall for wallpapering;
increase the resistance of the wall surface to mechanical damage and protect it from the occurrence of microcracks during operation;
protect the walls from damage during the subsequent removal of old wallpaper (especially true for drywall);
prevent the appearance of fungus and mold on the adhesive due to the preparations added to the solution;
hide darker spots on the surface of the wall (a special pigment primer is used to level out the high contrast in the color scheme), which are visible through light or thin tapestries;
reduce the consumption of wallpaper glue due to:

filling with a primer composition of microcracks, pores and small irregularities (having a high dispersion of particles, primer solutions penetrate deep into the wall material and stop pores and cracks into which glue would get);
creating a water-repellent layer on the wall, as a result of which concrete, plaster, fillers, drywall do not draw moisture from the adhesive mass: as a result, premature drying of the adhesive is prevented and, therefore, it is not re-applied.

Types of primers and their characteristics

The choice of a primer for wallpaper is completely determined by the type of material on the surface of which it is planned to apply the primer. Unfortunately, in various articles on this topic, the authors of popular and educational works mislead buyers, claiming that there is a special primer for non-woven, vinyl, paper wallpapers.

Why is there no primer for a specific type of wallpaper? Let's figure it out. For each type of wall material in the wallpaper adhesive, there must be a special component responsible for the adhesion of the adhesive mass to this particular surface. There are about 12 types of such surfaces. For convenience, round up to 10.

Then the manufacturer of glue, for example, for paper wallpaper, is obliged to produce 10 varieties of it (for each surface). There are also about 10 wallpapers with different bases. As a result, it turns out that at least 100 types of adhesive mass should be present on the building materials market. It is irrational neither for manufacturers, nor for sellers, nor for buyers.

With the advent of the primer, which acts as an intermediary between the wall and the adhesive, it is necessary to produce 10 types of primer, for each type of surface and 10 types of adhesive mass, for the corresponding base of the wallpaper.

The whole variety of primers on the construction market can be sorted according to the form of release, type of solvent, purpose, type of soil. Such knowledge will facilitate the search for the necessary goods.

Release form. On sale you can find:

liquid solution ready for use;
concentrate to be diluted;
dry mixes that require preparation.

By type of solvent. In production as a solvent are used:

water (water-based primer);
organic solvents (acetone, butyl alcohol, isopropanol, white spirit, etc.).

By appointment. Depending on the functions performed, the primer is divided into:

penetrating (for concrete, brick, stone);
reinforcing (drywall, GVL, all types of cellular concrete, gas silicate, etc.);
adhesive (for cases when it is planned to stick wallpaper on glass, tiles, plastic).

By type of soil. The primer can be acrylic, alkyd and mineral.

Acrylic primer (water emulsion). This is the most versatile type of primer. Acrylic can be used on almost all types of wall material: concrete, brick, wood, plywood, cement-based plaster, etc. By appointment, deep penetration, impregnating (strengthening) and adhesive are produced. Easily soluble in water, does not smell, dries quickly.

Produced in the form of: dry mix, concentrate, ready-made solution and primer-mix in a can. When special substances are added, the primer acquires antiseptic properties (used in the kitchen) or becomes pigmented (hides bright color spots). The most popular brands are: Alpina, Ceresit, Composite, Knauf, Perfecta, Prospectors.

Alkyd primer. This type of soil is based on alkyd resins diluted with organic solvents, mainly white spirit. The application is almost universal - all types of wall material with the exception of drywall, GVL, putties and plasters based on cement and gypsum (alkyds destroy them).

It has an unpleasant pungent odor, which occurs due to volatile substances released within 15-18 hours. After a long ventilation, the air is completely purified. Can dry up to 16 hours. Due to the presence of polymers in the composition, it forms a film on the wall surface that can withstand a large temperature difference (from -40 to +60 ° C) and mechanical stress.

The presence of a water-repellent film allows the use of a primer in the bathroom and in the kitchen. Available only in ready-to-use form. If it is necessary to dilute for a more liquid consistency, white spirit is used, regardless of what solvent the primer is based on. The disadvantages include the toxicity of the composition, which disappears after polymerization of the film.

It has varieties: glyptal, perchlorovinyl, polystyrene and polyvinyl acetate primer. Produced by well-known companies: "Kompozit", "Aura", "Tikkurila".

mineral primer. The composition of the mineral-based primer includes cement, gypsum and lime, which bind the base of the wall made of concrete, expanded clay concrete, brick (gas silicate brick and blocks), as well as plaster and putty with wallpaper glue. No smell, dries quickly.

Produced by Remmers, Ceresit, Caparol, etc. It is very difficult to find mineral and alkyd primers on sale. The reason lies in the fact that acrylic primers cover all the problems that arise before wallpapering, but at the same time they are much cheaper.

The choice of primer according to the type of wall surface

In terms of popularity, depending on the type of walls, the following primers are leading among buyers: Ceresit and Knauf. Their comparative characteristics are shown in the table (prices are taken for St. Petersburg in the middle of summer 2018).

Primer name	Packing	View primer	Surface type	Consumption per 1m2	Price from, rub.
Ceresit CT 17	10 l	acrylic	concrete, brick, drywall, wood, plaster and putty, gas silicate blocks	0.05-0.25 l	510
Ceresit CT 19	15 kg	acrylic adhesive	concrete walls, glass, tiles, plastic	0.3-0.75 kg	1165
Knauf "Tifengrund"	10 kg	alkyd	GKL, GVL, gypsum putties and plasters	100 gr	690
Knauf "Grundirmittel"	15 kg	alkyd	gas and foam concrete, silicate brick	0.2-0.3 l	3000
"Optimist"	10 l	acrylic	wood	0.1 l	547

To summarize: a primer for wallpaper, which one to choose? This is an acrylic primer: versatile, easy to apply, odorless and non-toxic.

If the choice does not suit you or you want to save money, then you can prepare your own soil.

Would need:

boiling water - 7 l;
drying oil - 0.1 kg;
laundry soap - 0.15 kg;
lime (slaked) - 2 kg;
bucket - 2 pcs.;
fine sieve - 1 pc.;
grater - 1 pc.

Soap is rubbed on a fine grater and diluted in 3 liters of boiling water. When it is completely dispersed, drying oil is poured in and the composition is stirred. 4 liters of boiled water are poured into another bucket and lime is poured.

The solution is also stirred. Water with soap and drying oil is poured into milk of lime and mixed. A slightly cooled home-made primer is filtered through a fine sieve. The cooled mixture can be used for its intended purpose.

Flow calculation

To determine the amount of primer required, it is required to calculate the area of the walls minus the openings of doors and windows. Multiply the resulting amount by 2 (number of passes) and multiply again by a factor of 1.1 (unforeseen losses of 10% are taken into account).

Then, using the table below, calculate (approximately) the number of canisters or bags of primer. A more accurate figure can be obtained directly when buying a primer - the packaging indicates the consumption in g / m 2 or ml / m 2.

Materials and tools

Without problems, you can prime the walls when available:

primer corresponding to the type of walls;
a basin (bucket) for mixing the primer;
cuvette for the mixture;
ladder;
fur roller with a long handle;
brush for processing places inaccessible to the roller.

Instructions for applying primer on the wall

How to prime the walls before wallpapering? The whole process consists of 3 technological operations:

preparing the wall for pasting with tapestries;
preparation of a primer mixture;
directly to the primer itself.

Preparatory work

It is possible to treat the surface of the walls with soil only after they have been prepared for wallpapering. At the same time, the preparatory work in a new building and a settled apartment can differ significantly.

In a new house, the walls are cleaned of construction dust and, if necessary, leveled with plaster or gypsum plasterboard (GVL). If an already occupied living space is being repaired, it will take much more time to bring the walls into working condition. Necessary:

remove the old finish (paint or wallpaper);
check the plaster, if it was applied earlier, for the absence of places lagging behind the wall and, if necessary, completely remove it;
inspect the walls for microcracks and repair them;
plaster the surface of the walls.

Detailed instructions under this paragraph are given in the material: "How to prepare walls for wallpapering."

Preparation of a mixture for priming

Depending on the form in which the primer is bought, the technology for preparing the mixture depends.

The finished primer does not require additional manipulations to bring it into working condition (just shake it up). However, experienced craftsmen, when working with concrete or reinforced concrete walls, dilute the primer for the first layer - acrylic compositions with water, alkyd with white spirit.
Concentrates are diluted in accordance with the recommendations printed on the package.
To prepare a primer solution from dry mixes, you will need a mixer, a bucket and a solvent (water or white spirit). The dry mixture is poured into the poured water in the proportion indicated in the instructions, and stirred with any object (trowel, stick, etc.) until lumps of the dry mixture disappear from the surface of the water. After that, the solution is mixed with a mixer until a homogeneous mass is formed.

Wall primer

The priming stage consists of a cycle of successive works.

A plastic film should be spread along the wall to protect the floor from splashes, which are formed during work with both a roller and a brush.
The primer is poured into the cuvette up to the level of the ribbed area.
A roller is lowered into the primer solution and wetted over the entire circumference.
On the ribbed surface of the bath, the roller is squeezed out - otherwise a lot of the mixture will be on the floor.

Priming starts from the bottom and goes up - in this case, the primer drops flow down the wall, and do not fly to the floor.
The soil must be rolled out with a thin film, avoiding traces of streaks. On the leaked solution, it is necessary to walk with the roller again.
In corners and hard-to-reach places, the wall is primed with a paint brush.
The second layer is applied after the first has dried.

Finishing work begins after the primer dries.

When can I start wallpapering?

After applying several layers of primer, many inexperienced finishers immediately start gluing wallpaper and, thereby, make a big mistake. Then a logical question arises: how long can wallpaper be glued after priming? Only after the primer has completely dried.

For aqueous solutions, this time can be from 2 to 15 hours, for alkyd primers - up to 35 hours. The estimated drying time of the solution is always indicated on the packaging. However, under the influence of various factors, it can fluctuate significantly.

In practice, experts check the readiness of the wall for pasting with a drop of water. If it spreads like a stain, you need to wait further. On a dry surface, it will slide down.

If the wallpaper is glued for a long time, you need to follow the following tips:

Do not use wallpaper glue and PVA glue, fine dispersion and water-based paints for priming.
The primer should dry well. It is better to wait an extra day and only then stick the wallpaper.
Spare no expense and apply a minimum of 2 coats of primer, even if the package says one pass is enough. Thus, the places missed during the first priming will be processed.
When buying a primer, correctly determine the type of wall material. It may be different. For example, cement plaster and plasterboard.
Carefully study the composition of the soil and recommendations for application. Under the guise of a good primer, PVA glue may turn out to be, or, like Ceresit CT 19, the primer should only be applied with a brush.
The primer for liquid wallpaper, if glue is not used, is applied at least 4 times.
Approach the choice of primer brand conservatively - buy products of familiar brands.