Plaster mixtures based on gypsum. Gypsum mixtures

If you need to level the surface of the walls in a room or update the facade of a house, plastering the walls is one of the most inexpensive and popular methods. Of course, when starting work, you must first become familiar with the types of plaster (especially when repair work there is not enough experience), because choosing the wrong mixture can ruin the final result. In this article we will tell you how to prepare a cement-based plaster mixture and dry gypsum plaster, as well as which type is suitable for walls.

Plastering walls

Let's compare cement-sand, lime and gypsum mortar for plastering walls according to their characteristics.

Gypsum plaster

The most popular now are dry mixes for plaster based on gypsum. Their main advantage is a very simple application process. This plaster is sold in finished form, you don’t have to mix anything, you just need to dilute it with water in the required proportions.


The most popular plaster mixture is from Knauf-Rotband, Volma Layer, Forman 10, Osnovit Gipswell, and Prospectors. They differ little in quality from each other, but some types cannot be used in wet areas.

We should also talk about universal mixtures for plastering walls from Knauf-Rotband. The price for a 30 kg bag is 360-390 rubles, which is more expensive than all similar options. There are also packages for sale in 5, 10, and 25 kg.


This mixture has been produced in Germany for half a century, and it appeared in Russia 20 years ago. It has become so popular that some are accustomed to calling any dry plaster by the name “Rotband”. building mixtures from plaster.

There are other gypsum plasters from Knauf-Goldband and HP START, but they are not in demand due to their high density.

"Rotband" has the following characteristics:

• Consumption 8.5 kg/sq. m. with a layer of 1 cm. One standard bag is enough to level 3.5 sq.m.
• The maximum layer thickness is 5 cm (on the ceiling only 1.5 cm, and if the height differences are greater, then leveling is done using).
• The minimum layer thickness is 0.5 cm (1 cm when laying tiles).
• The average drying time is 7 days, depending on humidity and thickness.
• Suitable for plastering walls and ceilings made of concrete, brick, and polystyrene foam surfaces.
• This mixture is not suitable for sealing joints between sheets of drywall. To do this, use gypsum-based putty - “Knauf Uniflot”. Read more about it in our article.
• Recommended for use in rooms with normal air humidity; can be used in the kitchen or bathroom.
• Color ranges from white to gray or even pink. It depends on the amount of natural impurities, and does not affect the characteristics of the material in any way.
• Shelf life – 6 months.

A thicker layer can be applied to the walls after the first layer of maximum thickness has completely dried. Applying more than one layer of plaster on the ceiling is unacceptable.

Among the main advantages of the Rotband mixture are the following.

• Obtaining a smooth surface.
• No cracks even on a thick layer of plaster (provided the technology is followed).
• The consumption of the mixture is half that of cement-sand types.
• Possibility of applying a layer of up to 5 cm in one approach without spraying the surface.
• The solution does not lose all moisture even on porous substrates or at elevated temperatures, which ensures uniform drying without delamination and without cracks.
• The composition does not contain harmful substances, completely safe.
• By adding polymer additives to the composition, the mixture provides enhanced adhesion, which allows it to be used even on the ceiling.
• The mixture contains special additives to increase working time with gypsum mortar.

To obtain the optimal consistency, the dry mixture is mixed with water in proportions of approximately 2:1, i.e., 15-17 liters of water should be used per 30 kg bag. For thorough stirring, use the mixer attachment on the perforator.
The video shows an example plastering works via Knauf Rotband:

Cement plaster mixture

The cement-sand mixture for plaster has the following composition:

• 1 part cement m-400;
• 3-5 parts of sand (if the cement is m-500, then you can increase it to 7 parts of sand).

Usually, during cooking, all elements are added “by eye.” You can use the following instructions.

• The preparation of a solution for plastering walls begins with sifting sand. To do this, you will need a sieve with cells of about 4 mm; for dry sand, you can use a finer mesh. When the sand is ready, begin making the solution. To do this, pour 2.5-3 liters of water into a 10-liter bucket.

To make the solution soft and pliable, you can add a little detergent to the water.

• Place three parts of cement into the mortar container and mix it thoroughly with a mixer.
• While stirring the solution with a mixer, add sand until the container is full. Start stirring the solution at low speeds so that the liquid does not splash out.
• As a result, the solution should have a viscous consistency, so that when the mixer is pulled out, a hole of 2-3 cm remains.

One batch is enough for approximately 1.5 square meters of plaster. m. walls. Basically, the consumption of the mixture depends on the thickness of the applied layer, so if you want to avoid over-consumption of material, then you need to buy the thinnest beacons, from 3 mm.

Dry cement based mixture

If you have no plans to mix the solution yourself, you can buy a ready-made mixture in dry form, which is simply diluted with water.

For example, the following types are available for sale:

• "Vetonit TT";
• "Volma Aquaslayer";
• "Magma";
• Plaster and repair putty “CeresitCT 29”;
• For facades: “Knauf Unterputz”, “Sokelputz”, “Grunband” (with polystyrene foam granules), “IVSIL GROSS”.

Cement-lime mixtures

Cement mortar in its pure form is not used so often because it has poor adhesion and increased cracking. In addition, not everyone has the opportunity to use expensive dry mixes, so lime plaster is a good alternative. This is very economical option a mixture that is convenient to work with due to its plasticity.

This option is also good for use in private homes due to its bactericidal properties - this is additional protection against fungus. Lime mortar is chosen mainly for rough finishing of walls in rooms with normal and low humidity. Unlike cement mortar, a lime-based mixture is well suited for plastering over shingles as it adheres well to the wood surface.

The disadvantages of this mixture include low grade strength, in contrast to mortar based on Portland cement. But this drawback does not play a special role; for plaster, compressive strength is not so important as a good level of adhesion and ductility.

Compound lime mortar for plaster:

• 1 part cement;
• ½ part slaked lime;
• 5 parts sand;
• 300 ml liquid soap.

The mixture turns out to be very elastic and adheres well to the wall; after drying, no cracks appear on the surface. Liquid soap adds a pleasant scent and increases elasticity.


Cement-lime mortar for plaster can be prepared in another way:

• 1 part lime sour cream;
• 2.5 parts sand;
• 0.12-0.25 parts of cement (depending on the amount of lime).

It is best to take quicklime and slak it yourself. 50 kg will require 13 buckets of water. Please note that when slaking, the lime will increase 2.5-3 times, so this work is done in a barrel of the appropriate volume.

This composition will stick well and stay on the wall, level with the rule and rub well. Costs for plastering 250 sq. m. such a mixture will cost approximately 22,200 rubles. (for material):

• 3 cubes of sand – 2000 rubles;
• quicklime 800 kg – 19,000 rubles;
• cement 150 kg – 1200 rub.

If we compare the costs with Rotband plaster, then for the same area it would cost 3-4 thousand rubles more.

Dry mixture based on lime-cement

You can purchase a ready-made dry mixture based on lime-cement.
The most popular types are:

• "Knauf Sevener" (universal mixture);
• "BEST";
• "Osnovit STARTWELL" and "FLYWELL";

Plaster mixtures for facades

In private homes, in addition to interior decoration, required external finishing walls Many owners, out of ignorance or in order to save money, plaster their facades with the same mixture that was used for interior decoration. This is strictly not recommended, since external walls require a mixture that can withstand the impact environment and at the same time not collapse. Below we provide a list of good plaster mixtures for finishing facades.

Mineral plaster mixtures

Mineral mixtures are produced on the basis of cement, therefore the packaging is marked “Polymer-cement mixture”. Thanks to a component such as redispersible powder, these mixtures have high adhesive qualities. Mineral mixtures are sold dry in bags.

Mineral plaster
Specifications:

• low cost;
• fire resistance;
• moisture resistance;
• good strength;
• high vapor permeability;
• long-term operation.

Acrylic-based plaster mixtures

Synthetic plaster mixtures are made on the basis of acrylic dispersion. They are sold ready-made in a liquid state and do not require additional preparation.

Acrylic plaster
Specifications:

• increased resistance to mechanical stress;
• moisture resistance;
• high adhesion to various surfaces.

Silicate plaster mixtures

The basis of silicate mixtures is potassium liquid glass. Silicate mixtures are produced in liquid form, ready for use. This type of mixture is ideal for finishing insulated walls mineral wool.

Silicate plaster
Specifications:

• excellent elasticity;
• good water resistance;
• good strength.

Silicone plaster mixtures

As you can easily guess from the name, this type of mixture includes an expensive material - silicone. For this reason, silicone mixtures are very expensive, but the price is well compensated by the advantages of this material.

Silicone plaster
Specifications:

• excellent moisture resistance;
• long-term operation;
• excellent adhesion;
• high elasticity;
• easy installation.

We looked at the main types of plaster for walls, ceilings and facades. We advise you to carefully study the characteristics of each of them and choose the most suitable option. You can either buy a ready-made mixture or prepare it yourself according to the proportions given above.

Plaster mixtures are used very widely in construction. Such compositions can be used for finishing indoor walls, ceilings, facades, columns, etc. The types of such mixtures on modern market there are several. And one of the most popular varieties is gypsum-based plaster. Many companies produce such compositions. However, some brands of gypsum mixtures are, of course, the most popular among consumers.

What criteria are used to evaluate

When choosing gypsum plaster, first of all you should pay attention to such characteristics as:

maximum permissible layer thickness;

drying time;

type of base;

Gypsum plasters are usually used only for finishing indoor surfaces. Such compositions are not used for facades. In most cases, manufacturers also recommend using such products only in dry rooms.

The best plasters

Most products of this type sold on the market today are of good quality. But still, the most popular gypsum plasters among consumers are:

"Rotband".

• "Gipswell."

  "Berhauf".

  "Prospectors".

  "Eunice Teplon".

Plasters "Rotband"

Dry mixtures on this brand belong to the group of universal products. Rotband plasters, among other things, contain special additives designed to increase their adhesive properties. Also, Rotband gypsum mixtures contain all kinds of natural impurities that determine their color. Depending on the manufacturer, such compositions can be:

• pink.

The pink Rotband plaster is considered to be of the highest quality. Such mixtures are produced by the Knauf Gips Chelyabinsk and Knauf Gips Kolpino enterprises. White and gray gypsum plasters of this brand are produced in Krasnogorsk, Krasnodar region and Astrakhan region. Such products can also be considered of sufficient quality. However, when using them you should still be a little more careful. White and gray Rotband plasters flow slightly down the wall, as a result of which horizontal waves can form on the surfaces.

Consumer Reviews

The advantages of Rotband plasters include, first of all, their plasticity, strength and the ability to achieve the smoothest possible surfaces. Judging by the reviews, it is very easy to work with such compositions, and on the walls, such finishing lasts as long as possible. Consumers also consider the advantages of Rotband plasters to be, of course, their excellent adhesive qualities, as well as minimal shrinkage.

Consumers consider some of the disadvantages of such gypsum mixtures to be that the “survival” of the solution is not very long. You should work with such plaster as quickly as possible or only mix a small amount of it at once. Also, consumers consider the rather high cost to be a disadvantage of Rotband.

Volma mixtures

The peculiarity of this brand of plaster is considered primarily to be plasticity and the ability to “breathe”. This mixture is produced by the domestic company Volma, founded in the 40s. There are several types of this plaster on the market today, differing slightly in composition:

“Volma-Layer”, intended for use in rooms with temperature changes.

“Titanium” and “Ultra” layers, the most resistant to cracks.

“Canvas” with mineral additives that maximize adhesion.

“Plast” is universal, very plastic.

“Lux” - designed for working on foam concrete.

This manufacturer also produces dry gypsum building mixtures intended for machine application: “Gips-Active” with additives that provide increased moisture resistance, and crack-resistant “Gips-Active Extra”.

Reviews of Volma mixtures

The most popular type of plaster of this brand among consumers is “Volma Canvas”. It is about this gypsum binder mixture that there are the best reviews on the Internet. Consumers consider the advantages of Volma Single formulations primarily to be ease of application and versatility. This mixture, as some masters note, can be used for leveling walls, texturing under decorative plaster and even, for example, making bricks.

Masters consider the main disadvantages of Volma Canvas to be too fast setting and the need for puttying after drying under finishing.

Dry building mixtures with gypsum binder "Gipswell"

The compositions of this brand are a cheap analogue of Rotband. Several varieties of such plasters are supplied to the market today. The most popular among consumers is the “Gipswell Osnovit” mixture. This plaster also comes in several series. For example, the mixture “Gipswell Osnovit T25” can be applied to walls in a layer of up to 8 cm. This plaster is also flexible.

In addition to the gypsum itself, Gipswell Osnovit T25 contains additives that increase the “pot life” of the solution and plasticity. Like Rotband, this plaster gives a very smooth surface and does not require additional putty.

Consumer opinion about Gipswell

Good feedback information about this plaster is available on the Internet primarily due to its ease of application. The compositions of this brand, as consumers note, provide a very high-quality finishing layer and are inexpensive. Low consumption is also considered an advantage of Gypswell gypsum construction mixtures.

If a thick layer of plaster needs to be applied to the surface, many consumers advise purchasing this T25 product. In this case, the finished finish is guaranteed not to crack. Also, judging by consumer reviews, Gipswell Osnovit T 25 practically does not shrink. Many craftsmen also note that the advantages of this product are that the solution prepared using it can not dry out for 1.5 hours.

Plaster "Bergauf": composition, description

The composition of gypsum-based mixtures from this manufacturer may include, in addition to the binder itself, the following components:

• quartz sand;

  mineral supplements;

  plasticizers.

The solution prepared from the Bergauf mixture hardens in about an hour. Additives make it flexible and easy to apply. Also, mixtures from this manufacturer have excellent adhesive properties.

Reviews of Bergauf mixtures

Consumers consider their low cost to be the main advantage of plasters of this brand. The price for dry gypsum mixtures "Bergauf", despite their high quality, is often lower than for some similar compositions, even from domestic manufacturers.

Despite the fact that these plasters contain sand, which, judging by consumer reviews, is noticeable even with the naked eye, they provide a fairly even and smooth finishing layer.

Plaster "Prospectors"

The mixture of this brand is excellent for finishing all types of surfaces. When using them, the same quality layer is obtained both on brick and foam concrete. A special lightweight component is added to the composition of the “Starateli” plaster, which allows to significantly reduce its consumption. Also, mixtures of this brand contain mineral components that ensure rapid hardening.

It is believed that the “Prospectors” plaster is simply excellent for application to surfaces such as under ceramic tiles, and just for wallpaper or painting. Dry mixtures based on gypsum of this brand can be applied to walls in a layer of up to 5 cm. The “lifetime” of a solution prepared using the composition of this brand is 45 minutes.

What do consumers think about “Starateli” plaster?

Consumers consider the main advantage of this brand of mixture to be its very low cost and good quality. The masters also include the following among the advantages of the “Prospectors” plaster:

smoothness of the finished surface;

ease of application;

optimal time grasping.

Experts consider that some of the drawbacks of this brand of product are that it sometimes contains large grains of sand. Therefore, when working with Prospector plaster, you should be a little more careful. Sand grains may leave grooves on the surface. If they are not repaired immediately, the wall may have to be puttyed later.

Gypsum mixture "Unis Teplon"

Plasters of this brand contain perlite, which reduces their setting time. Distinctive feature Unis Teplon products are lightweight and have maximum strength of the finished layer. Also, plaster of this brand can additionally protect the premises in the house from the street cold.

The lifespan of Unis solutions is approximately 50 minutes. They can be applied to walls in a layer of up to 5 cm.

Consumer Opinion

The main advantage of Yunis plasters is ease of application. Many consumers, judging by the reviews available on the Internet, consider dry gypsum mixtures of this brand to be simply ideal for beginners. The Eunice Teplon solution is very easy to apply to walls. In addition, the finished finishing layer does not require additional putty when used.

Consumers consider some of the disadvantages of Unis mixtures to be the difficulty in preparing the solution. This plaster must be kneaded long and thoroughly until all lumps are removed.

Instructions for use

Most gypsum plasters are thus characterized by their plasticity. That is, working with them is quite easy. But of course, in order to get a beautiful, durable finished finishing layer, when working with such compositions, you should follow all the required technologies.

Before starting plastering work, the surface must be cleaned of dirt, dust washed off and primed in two layers. Next, you can begin preparing the solution. In this case, the amount of dry gypsum plaster mixture should be taken so that the finished composition can be fully used while it remains “viable”. This is necessary in order to avoid overspending, as well as damage to the container in which the solution was prepared.

Like any other mixtures, it is advisable to apply gypsum to the walls using the “beacon” technology. That is, first place guide strips on the walls, and then level the mortar using the rule.

After about 20 min. After application, it is advisable to level the gypsum plaster layer with a special paint trowel. To make the finished surface as neat as possible, after a few more hours you need to moisten it with water and walk over it with a trowel.

Other mixtures: types and manufacturers

Of course, the most popular type of such compositions are plasters. But, of course, other gypsum mixtures are also produced based on gypsum. For example, when finishing premises the following types of compositions of this variety can be used:

• putties;
• mounting mixtures;
• adhesives.

There are many brands of such products on the market. But the best manufacturers they are considered to be the same ones that produce the highest quality plaster. That is, this is primarily “Rotband”, “Volma”, “Yunis”, etc.

Putties

This type of gypsum mixture is used for finishing the plaster layer. The advantages of such putties include, first of all, the smoothness of the finished surface, White color, speed of setting. In addition to finishing, gypsum products of this type can also be used to correct various types of surface defects before plastering.

Mounting mixtures and glue

Compositions of this type have the same advantages as plasters or putties. That is, they set very quickly and give a white surface that is easy to paint. Such mixtures are used when covering walls with gypsum boards or gypsum fiber boards.

Smooth walls are the key quality repairs. And one of the simple and reliable ways to level and decorate walls is to plaster them. In this article we will examine in detail all the issues related to gypsum plaster: what is it for, what are its features and specifications, pros and cons, and applications. We will also clearly show how to work with this material.

Application of gypsum plaster

Plaster mixtures based on gypsum are used primarily for finishing walls and ceilings of living rooms, as well as other rooms with normal humidity.

It can be placed on such bases as:

• brickwork and clay walls;
• on top concrete walls and cement plaster (requires concrete contact treatment);
• on old gypsum plaster, provided it has good strength;
• for cellular foam concrete, aerated concrete and expanded clay concrete;

Since gypsum is capable of absorbing moisture, it is used only for interior decoration in dry rooms when preparing the surface for painting or wallpapering.

Current prices:

Gypsum plaster

What's included

The main component of this type of plaster is building gypsum - calcium sulfate hydrate, obtained by firing gypsum stone and ground to a powder. The following may also be added to the composition:

• fillers that reduce weight and increase the thermal insulation properties of light plaster: perlite, vermiculite, foam glass or expanded polystyrene;
• plasticizers and retarders;
• additives that increase the whiteness of the surface - salts of various metals (zinc or titanium white) or lime;
• components that increase their strength;
• additives that regulate the setting time of the solution and its hardening time.

Gypsum plaster is an environmentally friendly material and is absolutely not hazardous to health. Moreover, due to its hygroscopicity, it is able to “breathe”, that is, absorb excess moisture and, on the contrary, release it, thus regulating the microclimate in the room.

A separate type of gypsum plaster is gypsum polymer. It is used for leveling brick and concrete surfaces. In some cases, gypsum polymer compositions can also be used for exterior finishing work.

Specifications

The quality of mixtures based on gypsum binder is regulated GOST 31377-2008 .

• According to this document, the main indicators of dry material include:
• humidity: moisture content is allowed no more than 0.30% of the total mass;
• volumetric weight: 800-1100 kg/m3 (loose) and 1250-1450 kg/m3 (compacted).

Properties of the prepared solutions:

• water consumption when mixing - 0.6-0.65 l/kg
• mobility: the ability to spread under the influence of its own weight; according to GOST 31376, the diameter of the melted sample of the prepared solution (~600 g) should not exceed 165 mm (±5);
• setting time - at least 90 minutes for machine-applied mixtures and 45 minutes for manual plastering;
• complete drying time - after 5-7 days; this indicator depends on the additives in the mixture and differs among different manufacturers; You can find out exactly how long it takes for the plaster to dry in the instructions on the package;
• ability to retain moisture without allowing it to drain: at least 90%;
• consumption for a layer of 10 mm is 8.5-10 kg/m2 (manual application) and 7.5-9 kg/m2 (machine application).

Properties of gypsum plaster in hardened form:

• compressive strength - 2.5 MPa;
• surface adhesion force - 0.3 MPa;
• density - 950 kg/m3;
• vapor permeability - 0.11-0.14 mg/ppa;
• thermal conductivity - 0.25-0.3 W/m*C;
• shrinkage - does not shrink

Although the vapor permeability (the ability to transmit water vapor) of plastered surfaces is not regulated by GOST, it is also an important technical characteristic that determines the scope of application of the plaster.

When purchasing gypsum mixtures, you should pay close attention to their shelf life. Due to their ability to easily absorb moisture, they cannot be stored for longer than 6 months from the date of release. After this period, their properties change, they begin to clump, and high-quality leveling of walls with them becomes problematic. It is also necessary to pay attention to the tightness of the packaging, which protects against excess moisture - you should not purchase plaster in torn bags.

Advantages and disadvantages

The main disadvantages of this material include

• Low moisture resistance;
• Low strength - a surface plastered with gypsum can be scratched or chipped quite easily.
• The cost is slightly higher than the cement-sand mixture, about 15-20%, but this is an insignificant disadvantage.

But still, gypsum has many more advantages.

• High plasticity: working with gypsum mortar is easier than with others; the labor intensity of the process is significantly reduced, and this is a significant plus;
• No shrinkage: for cement mixtures it is a couple of millimeters per square meter;
• Surfaces plastered with gypsum are smoother, without pores or graininess;
• Good adhesion: gypsum mortar adheres to the surface much better than sand-cement mortar; therefore, reinforcing mesh may not be used to strengthen the surface; it is required only in new stands due to possible shrinkage of the building;
• Good heat and sound insulation properties: a wall covered with a layer of gypsum retains heat and protects against noise better than concrete surfaces;
• It can be applied in a thicker layer (up to 50 mm) without reinforcing mesh;
• Light weight: walls covered with gypsum place less load on the foundation;
• Cost-effective: when comparing costs, many people pay attention only to the weight of the pack; however, it is necessary to take into account specific gravity mixture - after all, the consumption of gypsum per 1 m2 is 9-10 kg, while cement for plastering the same area will require 16-18 kg.

Expert opinion

Alexander Guryanov

Plasterer and decorator

Many people attribute the advantages of gypsum to a higher setting speed than cement-sand mortar. However, it is difficult to call this a significant advantage. Indeed, a surface treated with gypsum plaster hardens 1-1.5 hours faster than one coated with a cement composition.

You should not hesitate when working with it - smoothing out the solution that begins to harden will be problematic. Do not dilute the mixture too much if you are working on your own. It is better if one person does the cooking and the other does the plastering.

How to dilute dry mixture

Let's consider the preparation process and proportions of the gypsum solution. The dry mixture from the bag is poured into a prepared container already filled with water. According to the instructions, 1 kg requires 600-700 ml of liquid, that is, a 30-kg bag of plaster will require about 20 liters of water.

A small amount of solution can simply be mixed with a trowel or trowel. If it is difficult to make large volumes with your own hands, then it is better to use a hammer drill with a mixing attachment or a construction mixer.

The solution should stand for 3-5 minutes (reaction time of the components). Then it is thoroughly mixed again until all lumps disappear completely. The solution should be viscous and plastic, but under no circumstances should it flow off the instrument.

Gypsum plasticizers

However, at home, it is quite possible to make gypsum-based mixtures with your own hands, for example, quite plastic lime-gypsum. But the reaction between gypsum and water occurs quite quickly, so gypsum plaster hardens quickly.

To make a solution convenient to work with, one of the plasticizers must be added to it:

• diluted PVA glue, about 1% of the total volume;
• lime, used as a plasticizer and to increase hardening time;
• tartaric, citric acid will also slow down setting. WITH special liquids, for example, Plast Retard PE, can extend the setting time to several hours, prevent the appearance of cracks and improve the wear resistance of gypsum.

Use in damp rooms and outdoors

As we have already mentioned, gypsum plaster is capable of absorbing moisture, so its use in wet rooms and especially for facade finishing not advisable.

If it is necessary to make the gypsum surface moisture-resistant (for example, when preparing to lay tiles in the bathroom), it is coated with a deep penetration primer based on acrylic. Concrete contact soil is ideal for tiles.

Polymer waterproofing mastic, for example, Plitonit Gidroelast, also has good moisture-protective properties. It is applied on top of a thoroughly dried layer of plaster using a brush or roller in several layers. Each of them must be applied after the previous one has dried. Gluing of tiles is allowed only one day after application. It is recommended to fill the outlets of pipes and corners of various structures with the same mastic.

How to plaster with gypsum mortar (video)

You can work with gypsum plaster using a plastering station or manually. Machine application is a separate topic for discussion, and we will consider it in another article. And here we will analyze the nuances of manual application.

• the thickness of each layer can be 30-50 mm; if necessary, a new layer can be applied only after the previous one has dried;
• dry mixture consumption in the absence of large irregularities with a layer thickness of 1 cm is on average 9-10 kg/m2;
• gypsum mortar can be applied not only to brick, concrete surfaces and aerated concrete, but also to the previous layer of cement or gypsum plaster;
• surface leveling is carried out using beacon profiles or gypsum beacons - a small amount of mixture, which is applied pointwise or along a line to the wall and leveled; after they dry, a solution is poured between them, and then the entire plaster mass is leveled building rule; the thickness of the layer will be equal to the height of the beacons;
• to remove dust, protect against the shedding of small particles and strengthen the surface after plastering, the surface must be primed;
• to obtain a flat surface before painting or gluing thin wallpaper the walls are additionally puttied;

The video below shows all the stages of finishing: how to properly knead, apply and grout.

Grouting and glossing

Grouting is the manual removal of small irregularities, seams, and transitions between layers. Usually they are rubbed down after the plaster has dried. To do this, take a metal or plastic grater. The tool is moistened with water or a primer intended for application after plastering, and the surface is treated with circular or vertical and horizontal movements, periodically clearing the grater of the solution. Particular attention is paid to the corners.

The video above (time 5:35) shows the process of surface glossing - creating an ideal plane without finishing putty. Glossing and rubbing are very similar methods, using the same tools and techniques. But the difference is that this happens on plaster that has just set and is still wet. This saves time and eliminates the need to apply putty.

Finishing of aligned walls

After applying a layer of plaster, it is necessary to determine how further finishing will take place:

As you can see, gypsum mixtures are extremely in demand in finishing and repair work and are used everywhere.

We hope that this article was useful to you and that you found the information you were interested in. Please leave your questions and comments in the comments below.

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Regardless of the type of repair (cosmetic or major), a process such as plastering the walls is mandatory. It is safe to say that these works are the most labor-intensive and expensive. They cannot be performed without the use of special dry mixtures.

There are several types of this finishing material, but the highest quality, reliable and easy to work with are gypsum plaster mixtures.

As the name itself suggests, the basis of the material is gypsum.

In addition, we can also highlight the following main components that make up gypsum plaster:

• Filler. It has a light structure and consists of small fractions. The presence of filler ensures the stability of the shape and structure of the plaster. Thanks to this, gypsum plaster mixtures are extremely economical to use.
• Polymers. They give the mixture properties such as elasticity and impermeability. In addition, the presence of polymers guarantees a high level of adhesion of the mixture to the working surface.

The composition of gypsum plaster allows it to be used for the following purposes:

• Masking and sealing a variety of defects and irregularities on the surface.
• Formation of slopes and corners (see).
• Alignment of walls that have a blocked corner.

Note. Plaster gypsum mixture is available in the form of a dry powder, packaged in convenient and airtight bags.

Main advantages

This can be clearly seen in the table below:

Types of plaster	Cement	Plaster	Result
Properties
Light weight	–	+	The mixture adheres well to the surface, does not form sagging, it is possible to use the machine method of laying, high speed of work
No need for post-processing of the mixture on the surface	–	+	Immediately after the putty layer has hardened, you can begin finishing the surface.
Short hardening time	–	+	The time required for finishing work is significantly reduced
Low density	–	+	Minimum consumption of working material is ensured
Does not shrink	–	+	No cracks form after the mixture dries
Environmental friendliness	–	+	Helps create a beneficial and healthy indoor microclimate

Note. From all of the above, it follows that gypsum plaster mixtures are the most economical and convenient type of dry plaster, the price of which is affordable for every buyer.

Usage

You can familiarize yourself with the preparation process from the instructions printed on each package.

Stages of work

• First of all, you should pay attention to the temperature inside the room. It should be within +5+30 degrees Celsius.
• Before starting finishing work, it is necessary to prepare the surface: By cleaning it from dust, old plaster (see How to remove old plaster from walls without problems), dirt.

It is also necessary to remove all foreign objects:

• Nails.
• Hooks.

Advice. If it is not possible to remove them, they must be treated with a special anti-corrosion liquid.

The surface on which the gypsum plaster mixture will be applied must be treated with a primer:

• If working surface strongly absorbs moisture, for example, aerated concrete or brick, it will have to be coated with a primer several times.
• This is necessary to ensure good adhesion of the mixture to the surface.

Now you can start preparing the solution:

• To do this, pour the powder from the bag into a deep container and pour clean water at the rate of 0.6 - 0.8 liters of water per 1 kg of dry powder.

• If such devices are not available, you can stir manually. I would like to note that the prepared mixture must be used within 30 minutes.
• Otherwise, the solution will begin to dry out and become unsuitable for further use.
• It should also be noted that foreign components should not be allowed to get into the finished plaster.

Note. This may disrupt its composition, which will result in it losing its properties.

The gypsum plaster mixture is applied to the surface in a layer whose thickness ranges from 50 to 79 mm:

• Work must begin from top to bottom. After the layer of plaster has been laid out, it should be leveled.
• To do this, you can use a special tool - a rule that has the shape of the letter h. After an hour, remove excess plaster as usual.
• The plastered surface can be completely leveled using a construction spatula with a wide base.

• If no traces remain, it must be thoroughly wetted and rubbed with a sponge grater. This should be done with careful circular movements.
• To achieve maximum flat surface plaster, after approximately 24 hours this procedure can be repeated.

Note. One of the advantages of this solution is that plastering with a gypsum mixture eliminates the need for subsequent treatment of the working surface.

• For quick and high-quality drying of the solution, it is necessary to completely eliminate the presence of drafts in the room.
• In addition, you should also avoid allowing direct sunlight to hit the surface.
• The final stage of work is to ventilate the room. Thus, excess moisture will be removed from it.

The video in this article will clearly introduce the stages of working with gypsum plaster.

What to look for when choosing a material

When purchasing gypsum-based plaster (plaster and gypsum mixtures), experts recommend paying attention to its manufacturer. In the construction and finishing materials There is quite a large selection of this kind of mixtures. A positive result can only be achieved if the product is released by a well-known company whose products have received positive user reviews.

Gypsum plaster mixtures are produced by the following brands:

• Baumit;
• Knauf (see Knauf façade plaster: material characteristics);
• Litox;
• Polirem;
• ArtEko, etc.

According to experts, Knauf plaster plaster mixtures are the highest quality and most reliable to use. Both experienced and novice craftsmen can easily work with it.

Gypsum-based plaster produced by this manufacturer has the following positive properties:

• Uniform combination of dry powder with water.
• Can be used for finishing different surfaces: brick, gas or foam concrete, tiled, concrete, etc.
• There is no shrinkage process and, as a result, the formation of cracks after drying.
• Economical consumption of working solution.
• Maximum even distribution on the surface.
• Minimizing the time required for finishing work.
• Environmentally friendly.

Note. It is also important that the Knauf gypsum plaster mixture has the property of sound insulation. This is extremely important. If Finishing work are held indoors panel house where there is poor sound insulation.

In conclusion

This became possible due to the fact that in the production process such an environmentally friendly natural component as gypsum is used as a base.

As a result of the use of special additives, gypsum plaster mixtures produced by this brand do not spread on the surface. This makes it possible to use them when working on an angled surface, finishing or leveling slopes and corners.

By choosing plaster from this manufacturer, you can be completely confident that the mixture will perform all the functions assigned to it, and the working surface will have an attractive appearance for a long time.

In our renovation, we settled on the one in the bathroom. To complete the process, all we have to do is sand the seams and putty the ceiling. So we come to a slightly unusual variety cement mixtures- These are polymer-cement putties and polymer-cement grouts.

The composition of these mixtures is similar to tile adhesive- the same gray or white cement, the same cellulose thickener, polymer. But either fine quartz sand (fractions up to 0.3 mm) or marble or limestone flour with the same particle sizes is used as a filler.

Polymer-cement putties

Let me remind you that puttying is the final leveling of the surface, with a layer of 1 mm to 1 cm, before subsequent plastering, painting, wallpapering, etc. Polymer cement putties are used both for facade works, as a finishing layer on lime-cement plasters, and when leveling surfaces inside dry and wet areas. When working with these putties, you must remember that the working capacity of a solution based on them is 2-3 hours. In this case, the coating turns out to be quite hard - the skin must be chosen larger.

Polymer cement grouts

A type of polymer-cement putty - grout for tile joints. Grouts are divided into white, gray and colored. White and gray are completely identical in composition to cement putties. When producing colored cement, an inorganic pigment is introduced into white or regular cement. Grouts play both a decorative and protective role in the tile covering. Thanks to the polymer introduced into the cement, as a rule, this is a type of vinyl acetate (remember PVA glue), grouts do not allow moisture to pass into the tile joints, thereby protecting the adhesive layer.

Grouting compounds are limitless possibilities designer's imagination. The picture shows a dark brown grout into which bronze powder was introduced during mixing. The effect is a dark brown metallic color.

White grout can be tinted with tinting pastes, resulting in completely unusual colors. By the way, cement-based grouts play a role in mosaics the most important role, also acting as an adhesive solution: the solution holds the mosaic map grid. Ground marble or limestone is used as a filler in grouting compounds, since quartz can scratch the glaze of the tile.

You can use white or gray putty as mosaic adhesive, but in this case it is necessary to add acrylic latex (or acrylic primer) to the mixing water.

Gypsum-based mixtures

These are the lightest and most convenient compositions to work with. Their only drawback is that they can only be used indoors in dry rooms.

Gypsum is known to be a fast-setting and hydrophilic (water-absorbing) compound. The same polymers are introduced into gypsum-based mixtures in order to reduce water absorption and increase adhesion (adhesive force), as well as inhibitors - substances that slow down the hardening reaction of gypsum. The simplest example inhibitor - food or technical citric acid. If, when mixed with water, you add 10-20 grams of citric acid per 1 kg of gypsum, then the gypsum mass will slow down its hardening to 30-40 minutes.

Gypsum mixtures are divided into:

• Gypsum putties

They consist of a gypsum binder (we will further call it gypsum, although a mixture of alpha gypsum and anhydride is used in production), quartz or limestone filler, cellulose thickener and redispersible polymer. Gypsum putties can be applied in a layer of 1 mm to 1 cm.

Attention! Gypsum is calcium sulfate - CaSO4. When painting a surface leveled with such a mixture, it is necessary to use acid-resistant paints. And accordingly, observe safety precautions: plaster that gets into even a small wound causes very unpleasant sensations.

• Gypsum plasters

Dry mixes that have earned the highest recognition among professional builders. They are lightweight, easy to work with, do not shrink (unlike lime-sand-cement putties), quickly harden on the surface and have a fairly high working capacity - from 30 minutes to 1 hour.

You can make the simplest gypsum plaster in your kitchen: take 10 kg of gypsum, 1 kg of slaked lime, 50 grams of citric acid, mix it all with water and mix until the consistency of thick sour cream is obtained.

The finished mixture can be used to seal grooves, level a wall or ceiling. Although industrially prepared plasters also contain fractionated sand, a cellulose thickener and a redispersible polymer. To give the plaster volume and lightness, expanded perlite or vermiculite - light, weightless sands - are added to some compositions. The average consumption of such plaster is 7 kg/m2 with an application layer of 1 cm.

• Gypsum-based assembly adhesives

If we want to glue a sheet of plasterboard, mineral insulation, or a sheet of foam plastic to the wall, this is best suited for us assembly adhesive based on gypsum. The composition is similar to that of tile adhesive, with the exception of the main component: instead of cement - gypsum.

• Gypsum floor mixtures

Putties based on a polymer binder

They differ from the above types of dry mixes in that they do not contain either cement or gypsum. These are putties consisting of almost 100% filler - finely dispersed limestone or marble flour, cellulose thickener and redispersible polymer.

Putties of this type are very convenient in application and subsequent processing (sanding), suitable for subsequent painting or wallpapering. When diluted, they work for up to 24 hours. But these putties are not intended for leveling surfaces for laying tiles. Putties based on a polymer binder are used only inside dry rooms as a finishing layer for leveling the surface and are not used without further coating.