Features of dry building mixes based on gypsum binder. Plaster mix on a cement, gypsum and lime base: ready-made dry mixes, composition and proportions. Cement-based dry mix

It must satisfy very different requirements, sometimes almost the opposite: high vapor permeability and insensitivity to the action of water, for example. No less controversial is the desire to obtain a material with low consumption and very high hiding power. However, gypsum plasters can fulfill this condition as well.

Is a typical sedimentary mineral based on calcium sulfate. From the point of view of finishing, the material on its base is attractive in that it creates a surface in a perfect white color. No additional filler or paint underneath light wallpaper, for example, is not required. However, these are not all the distinguishing features of the material.

The fundamental difference between decorative and leveling plasters is in the setting speed, or, more precisely, in the time while the layer remains plastic. For leveling plaster, it is advisable to reduce this period to a minimum, but for the decorative option, the opposite is true: as long as the layer retains plasticity, it can be processed special tools to achieve a decorative effect.

Gypsum is quite suitable for both purposes, but only in the presence of polymer additives, which regulate the plasticity period and setting time. In this case, the filler can be different, but only fine-textured.

Advantages

Material advantages:

Gypsum plaster is very plastic, even the usual one for leveling walls can be smoothed out to a glossy shine. Modulating gypsum-based - best material to create not just complex reliefs, but relief images.
To apply gypsum plaster it can be done both manually and by machine: the modifiers added to the mixture regulate the mobility of the solution within a very wide range.
Excellent White color serves as an ideal base for any decoration: coloring, image formation.
The composition of gypsum plaster with your own hands can include many additional components that noticeably change the properties. So, the additive allows you to apply the mortar to concrete walls with the same ease as conventional lime mixtures. And the addition of perlite significantly enhances thermal insulation properties plaster: this composition is recommended for finishing concrete walls, since the thermal conductivity of the latter is unpleasantly high and the walls are cold to the touch.
Water vapor permeability makes gypsum-based finish one of the most environmentally friendly and safe coatings.
Increased hygroscopicity may turn out to be not only a disadvantage: when pouring from above, for example, a stain from water, provided that the latter was clean, will disappear by itself after 2-3 days. The material not only absorbs, but also gives off moisture in case of its excess.
The solution consumption is 1.5 times less than that of the most economical one.

Flaws

Disadvantages of gypsum plaster:

An obvious important disadvantage is its high hygroscopicity. The material absorbs moisture, and therefore is not used for either external works, nor for the decoration of rooms where high humidity is provided - a bathroom and a kitchen, for example.
However, the Rotband website has information about the types of gypsum plaster that can withstand moisture, but in the absence of direct contact with water. That is, this option is still not suitable for a bathroom.
For the same reason, gypsum-based decorative plasters cannot be washed. The maximum is dry cleaning and the use of a barely damp cloth when heavy dirt appears.
The plaster finish is not mechanically strong: you should not use sharp instruments to check its integrity.
The hardening period of gypsum plaster is too short - 50 minutes in a container before hardening. Considering that during this time it is necessary not only to apply a layer, but also to create decorative surface, you need to prepare the solution in small portions, which complicates the work somewhat.

Scope of use

The area of use of the GS is determined by its properties and composition.

Living quarters - due to its high vapor permeability and environmental friendliness, this is the kind of finish that is recommended for the nursery. On the other hand, she cannot be washed, so the solution to this issue depends on the owner of the apartment. In the living room or bedroom, the material is used without restrictions.
Even the most "waterproof" version does not tolerate direct contact with water. And if for the kitchen certain varieties can be used, then for the bathroom they cannot.
Plaster leveling compounds are an excellent base for other finishes. And they are still in demand when it is necessary to create a truly snow-white surface of a wall or ceiling. The layer thickness can vary from 5 to 50 mm, with reinforcement - up to 70 mm. The material is seized within 80–150 minutes, and completely dries up in 5–7 days.
It is applied by GSh on, brick wall, and even metal surface if protected with an anti-corrosion agent. When finishing surfaces with high porosity - gypsum fiber, you should use a special primer. On the wooden surfaces GSh is not applied: low adhesion.
Gypsum-based modeling plasters are used for the decoration of residential premises only. Images and ornaments are created in the usual way for this kind of plasters - with a stamp, a roller with a relief surface or the movement of a trowel.

Solution and its preparation

Despite the simple composition, it is recommended to work with the ready-made gypsum mixture, since the polymer additives added in production conditions significantly improve the finishing properties. At home, such a uniform distribution of the substance cannot be achieved.

Composition and structure

Typical mix composition:

gypsum;
fine fraction filler - with grain up to 1.5 mm;
additional additives.

This limitation is fines, reduces the amount decorative options... In fact, only modeling plasters are obtained on the basis of gypsum. Leveling compounds are much more popular.

The solution, as already mentioned, is prepared in small portions. After 50 minutes, the mixture solidifies completely. 25-30 minutes is the period of sufficient plasticity of the material.

And now let's analyze the composition, proportions and recipe for gypsum plaster.

From this video you will learn about the technology for applying gypsum plaster on lighthouses:

Recipes

With sawdust

There are quite a few recipes for preparing a mixture - we mean leveling types:

1 volume fraction of Rotband or Ecogypsum mixture;
1 share of crushed sawdust;
3-4 shares.

The ingredients are dry mixed, and then added in small portions to water.

The composition has good sound and heat insulation qualities.

Gypsum-chalk

Gypsum-chalk plaster is more suitable for finishing, it is prepared as follows:

crushed chalk - 3 kg;
gypsum - 1 kg;
5% solution of wood glue.

Gypsum and chalk are mixed, and then wood glue is added to the container with the ingredients until a pasty mass is obtained. Since the solution sets quickly - there are no modifiers here, then it should be prepared from a dry mixture a little.

Lime-gypsum

Lime-gypsum plasters for interior decoration are even more popular: they grasp more slowly and tolerate mechanical stress better.

The composition is as follows:

water is added to 1 share of gypsum with stirring until a gypsum dough is obtained;
Dissolve 3 parts of lime in water;
then the solutions are thoroughly mixed.

From the ready-mix

Pour a dry mixture of gypsum plaster into a container with water at the rate of 0.5–0.7 liters per 1 kg of the mixture, mix until smooth. Mixing can be done either manually or with a mixer attachment on a drill.
The solution should stand for 3-5 minutes, then it is mixed again and used.

The composition cannot be diluted with water again. Next, the technology of applying gypsum plaster is considered.

Application technology

So, how to properly plaster walls with gypsum plaster? The finished solution should be applied within 30 minutes. For this, a trowel or a falcon is used - a square platform on the handle. The latter is more often used when working with a ceiling.

The resulting solution can be applied in a layer of 10 to 50 mm, on the ceiling - 30 mm. If a thicker layer is required, then the second should be applied only after 24 hours.
Align the layer with the rule.
After 45-60 minutes, the GSh layer is smoothed out with a metal spatula or treated with a decorative tool.
If the surface is prepared for wallpaper or paint, then after 20 minutes, when the layer is no longer pressed with a finger, the coating is moistened with water, and when it becomes dull, rubbed with a sponge. The movements are circular. Then the wall is smoothed with a spatula. After a day, this procedure is repeated. This gives a smooth surface that does not need putty.
Drafts should be avoided on the first day. The coating dries completely within 5-7 days, after which you can proceed to further finishing.

Read about the consumption of gypsum plaster per 1 m2 below.

The video below will tell you about applying gypsum plaster without beacons:

GS consumption

Gypsum plaster is one of the most economical coatings - leveling plaster is meant. When forming a layer of 10 mm, the consumption is 10 kg per 1 sq. m.

For comparison, a lime leveling plaster needs at least 14–15 kg.

Requirements for the quality of materials

Dry quality building mixtures on gypsum binder, it is regulated by GOST 31376-2008. The mixtures are subject to verification, ready-made solutions and the actual plaster layer.

Dry formulations must meet the following requirements:

the mixture does not include grains with a diameter of 5 mm. Granules with a diameter of 1.25 mm can be no more than 1.0% of the mass, with a diameter of 0.2 mm - no more than 12% and with a diameter of 0.125 mm - no more than 15% .;
moisture content of the mixture - no more than 0.3% by weight;
the activity of natural radionuclides must comply with the requirements of GOST 30108.

Ready-to-use mixtures must meet the following conditions:

setting time at manual way- 45 minutes;
setting time in machine production - 90 minutes;
the ability to retain water is at least 90%;
the mobility of the mixture must comply with GOST 31376: the diameter of the spread is 165 mm with an error of 5 mm. This indicator can be changed at the request of the customer.

The finished coating must meet the following requirements:

bending strength - not less than 1 MPa;
compressive strength - not less than 2 MPa;
adhesion strength - not less than 0.3 MPa.

If necessary, find also the average density of the plaster layer.

Popular brands and prices

Numerous companies producing materials for construction finishing, plaster mixes were not ignored either.

The most famous in our market are gypsum plasters "Rotband" from Knauf (Knauf). It is these compounds that can be used in relatively humid rooms. It can be used for both manual and machine application. Package weight - 30 kg, the price of gypsum plaster - from 290 to 355 rubles.
The manufacturer of gypsum plaster "Volma" is no less popular. It is a leveling plaster with excellent adhesion to any type of surface other than wood. Package weight - 30 kg. Price - from 270 to 355 rubles.
Dry gypsum mixes from the Osnovit company compete with them. Both white and gray gypsum plasters are available. Package weight - 30 kg, cost - from 260 rubles.
A variety of building materials, including gypsum plasters, intended for leveling and finishing concrete, brick, and other surfaces, are produced under the Prospectors brand. Packing price - from 270 to 305 rubles.
Gypsum plaster from Vetonit is designed for both manual and machine application, the cost of a package weighing 20 kg - from 394 rubles.

In the vast majority of cases, gypsum plaster belongs to the category of leveling mixtures. She is perfect for living rooms with low humidity and stable microclimate.

This video will tell you about the use of Rotband gypsum plaster from Knauf:

Plaster mixes are widely used in construction. Such compositions can be used for interior walls, ceilings, facades, columns, etc. There are several types of such mixtures on the modern market. 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 are the criteria for evaluating

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

maximum permissible layer thickness;

drying time;

type of base;

Gypsum plasters are usually used only for interior 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 of the products of this type sold today on the market are of good quality. But still the most popular gypsum plasters among consumers are:

Rotband.

Gipswell.

Bergauf.

"Prospectors".

"Eunice Teplon".

Rotband plasters

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

pink.

At the same time, the pink plaster "Rotband" is considered to be of the highest quality. Such mixtures are produced by Knauf Gips Chelyabinsk and Knauf Gips Kolpino. White and gray gypsum plasters of this brand are produced in Krasnogorsk, Krasnodar Territory and the Astrakhan region. Such funds can also be considered to be of sufficient quality. However, when using them, you should still be a little more careful. White and gray Rotband plasters run slightly down the wall, resulting in horizontal waves on the surfaces.

Consumer reviews

The advantages of Rotband plasters are primarily attributed to their plasticity, durability and the ability to achieve the smoothest surfaces possible. It is very easy to work with such compositions, judging by the reviews, and on the walls in the future, such a finish lasts as long as possible. Also, consumers consider the advantages of Rotband plasters, of course, to be their excellent adhesive qualities, as well as minimal shrinkage.

Some disadvantage of such gypsum mixtures, consumers consider not too long "vitality" of the solution. You should work with such a plaster as quickly as possible, or mix not a very large amount of it at once. Also, consumers refer to the disadvantages of "Rotband" quite high cost.

Mixes "Volma"

The peculiarity of the plaster of this brand is considered primarily 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, slightly differing in composition:

Volma-Layer is intended for use in rooms with temperature extremes.

"Layer Titanium" and "Ultra", maximally resistant to cracking.

"Canvas" with mineral additives that maximize adhesion.

"Plast" is versatile, very flexible.

"Lux" - designed for work on foam concrete.

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

Reviews about the mixtures "Volma"

The most popular type of plaster of this brand among consumers is Volma Canvas. It is about this gypsum binder mixture on the Web that there are the best reviews. The advantages of Volma Holost compositions are primarily attributed to ease of application and versatility. This mixture, as noted by some masters, can be used for leveling walls, texturing for decorative plaster and even, for example, sculpting bricks.

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

Dry building mixes with gypsum binder "Gipswell"

Compositions of this brand are a cheap analogue of Rotband. Several varieties of such plasters are supplied to the market today. The most popular with the consumer is the mixture "Gipswell Osnovit". This plaster also comes in several series. For example, the mixture "Gipswell Osnovit T25" can be applied to walls with a layer of up to 8 cm. Also, this plaster is plastic.

In addition to the gypsum itself, the composition of "Gipswell Osnovit T25" includes additives that increase the "pot life" of the solution and plasticity. Like Rotband, this plaster gives a very smooth surface and does not need additional filling.

Consumer opinion about Gipswell

Good feedback about this plaster on the Web are primarily due to its ease of application. The compositions of this brand, as noted by consumers, provide a very high-quality finishing layer and at the same time are inexpensive. Low consumption is also considered an advantage of Gipswell gypsum building mixtures.

If the plaster needs to be applied to the surface in a thick layer, many consumers advise purchasing this particular brand of T25. The finished finish in this case is guaranteed not to crack. Also, judging by the reviews of consumers, "Gipswell Osnovit T 25" practically does not shrink. To the pluses of this tool, many masters also refer to the fact that the solution prepared with its use is capable of not drying 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 freezes in about an hour. Additives make it pliable and easy to apply. Also, mixtures from this manufacturer have excellent adhesive properties.

Reviews of mixtures Bergauf

The main advantage of this brand of plasters, consumers consider their low cost. The price for dry gypsum mixes "Bergauf" with their high quality is often lower than for some similar compositions, even from domestic manufacturers.

Despite the fact that the composition of these plasters includes sand, which is noticeable, judging by the reviews of consumers, even with the naked eye, they give a finishing layer quite even and smooth.

Plaster "Prospectors"

The mixture of this brand is excellent for finishing all types of surfaces. An equally high-quality layer when using them is obtained both on brick and on foam concrete. A special lightweight component is added to the plaster "Prospectors", which significantly reduces its consumption. Also, mixtures of this brand contain mineral components that provide fast hardening.

It is believed that the plaster "Prospectors" is just great for applying on surfaces both under ceramic tiles, and just under wallpaper or painting. It is possible to apply dry mixes on a gypsum base of this brand on the walls with a layer of up to 5 cm. The “life” of a solution prepared using the composition of this brand is 45 minutes.

What do consumers think about the plaster "Prospectors"

Consumers consider the main advantage of the mixture of this brand to be a very low cost with good quality. Also, the masters refer to the advantages of the plaster "Prospectors":

smoothness of the finished surface;

ease of application;

optimal time grasping.

The masters believe that some disadvantage of this brand is that large grains of sand are sometimes found in its composition. Therefore, when working with plaster "Prospectors" you should be a little more careful. Grains of sand can leave grooves on the surface. If they are not repaired immediately, the wall may have to be putty later.

Plaster mix "Yunis Teplon"

Plasters of this brand contain perlite, which reduces their setting time. A distinctive feature of the "Unis Teplon" products are their low weight and maximum strength of the finished layer. Also, the plaster of this brand is able to additionally protect the premises in the house from the outside cold.

The life span of Unice solutions is approximately 50 minutes. They can be applied to the walls in a layer 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 Web, consider dry gypsum mixes of this brand to be simply ideal for beginners. It is very easy to apply the Unis Teplon solution to the walls. In addition, the finished finishing layer, when used, does not require additional puttying.

Some of the disadvantages of Yunis mixtures are considered by consumers to be the difficulty in preparing the solution. You need to knead this plaster for a long time and thoroughly before removing all lumps.

Instructions for use

For the most part, gypsum plasters are thus plastic. That is, it is quite easy to work with them. But of course, in order to get a beautiful, durable finished finishing layer, all the required technologies should be observed when working with such compositions.

Before starting the plastering work, the surface must be cleaned of dirt, washed off the dust and primed in two layers. Then you can start preparing the solution. In this case, the amount of dry gypsum plaster mixture should be taken such that the finished composition could be fully used for the time while it retains its "viability". This is necessary in order to avoid waste of funds, 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 lighthouse technology. That is, first put the 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 painting float. To make the finished surface as neat as possible, after a few more hours it must be moistened with water and walked over it with a trowel.

Other mixtures: types and manufacturers

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

putties;
assembly mixtures;
adhesives.

There are many brands of such products on the market. But the best manufacturers are considered the same ones that produce the highest quality plaster. That is, it 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, quick setting. In addition to finishing, gypsum products of this variety can also be used to correct various kinds 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 stain. Such mixtures are used for wall cladding with gypsum board or gypsum fiber boards.

Dry gypsum plaster mix has recently come to the sales market. But it has many fans, because it is not difficult to prepare it, and the installation is not difficult.

Today dry gypsum plaster mix will be considered. You will learn its composition and properties. After that, cook it yourself and reduce the cost of finishing. Instructions for manufacturing will be offered and on the video in this article you can clearly see the process of this work.

Basically, dry gypsum plaster mix is used for interior finishing work. Gypsum plaster is used for preliminary leveling of vertical and horizontal surfaces, just before applying the decorative finish.

Attention: At the same time, it is very important that gypsum leveling mixtures can be used only in those rooms in which the moisture level is not more than sixty percent. If this is a large room, and there is a lot of moisture in it, then it is better to use hydrophobic finishes in this case.

So:

Before starting work, you need to take the fishing line and pull the drawing plane diagonally. So you can immediately see the deviations and calculate how much dry powder you need.
If the layer is large, then it is best to use a construction mesh that is attached to the wall. In this case, the grip will be better.
It is possible to settle gypsum mixtures with a thick layer. This will not harm the strength of the finish. Consequently, with the help of such mixtures, both significant irregularities and small defects can be leveled.
In addition, such plaster is often used not only in cases when it is necessary to eliminate the relief on certain surfaces. It is also often used to level walls with a collapsed level.

What is attractive

Dry plaster mix has a lot of advantages:

The price is quite attractive, anyone can afford it;
You can cook with your own hands without any problems, and it does not take much time;
You can give almost any shape to the finish;
The finish adheres well to any plane, in this matter it is universal;
Allergens and toxins are completely excluded in this material. so it is completely safe;
Not required finishing, this does not need to be spent;
It is light enough and therefore the weight of the wall will not increase much.... This is good for load-bearing walls.
With the help of the mixture, you can mask and repair a variety of surface defects. In addition, slopes or corners can also be formed.

Attention: The disadvantages of this material include a low level of hydrophobicity, and, consequently, the impossibility of using plaster when decorating the facade.

The composition of the gypsum mixture

Dry gypsum plaster mix has rather simple components:

Attention: Gypsum plaster dry mix is commercially available, but if you have a large amount of work, then it is better to do it yourself. In this case, you will win 50% of the cost of the finished material.

The main components of standard dry mixes are gypsum and lightweight fillers. They also contain modifying additives in their composition. The quality of the material, the level of its adhesion and many other characteristics depend on them.
All manufacturers use different compositions components, but ready-made mixtures, in general, have similar properties that meet certain standards and norms.
To make dry mixes convenient to store and use, they are supplied in special packages. Usually, gypsum finishing materials are packaged in specially designed kraft bags. One such bag weighs an average of fifteen or thirty kilograms. Most builders prefer this packaging.
Store the mixture in a dry place. In this case, it is very important that it is well ventilated. In order for the packaging to retain its properties, micro-perforation is done.
In case the humidity warehouse exceeds the norm, the mixture becomes unusable, hardens. That is why, before buying factory plaster, check the quality of the purchased material.

Attention: It is very important that the mixture can be stored from six to twelve months. After this, important material properties are lost. In this case, a high quality finish is not guaranteed.

If you do not have big amount funds, but you need to finish large room, then you do not need to spend money on its purchase, since you can cook it yourself.

Rules for the preparation of gypsum composition

Dry plaster mix is made according to certain rules:

Attention: If you make a purchase of components in winter time, then you should not do it on open trays. The composition freezes and loses its astringent properties. Also, give preference to well-known manufacturers and refrain from buying unknown mixtures.

To begin with, the gypsum should be passed through a sieve and make the fraction homogeneous. This will get rid of clumps and debris.
After that, the powder must be placed in a container and water must be added in small portions. Stir well until a plaster dough is obtained.
In the composition that will turn out, it is necessary to add a lime solution. And again mix everything thoroughly.
For kneading, you can use a drill with a nozzle, it will allow you to do everything quickly and the mass will turn out to be as homogeneous as possible.

Attention: I would like to note that you need to mix thoroughly, just do not need to mix for more than one minute. Otherwise, the solution will lose strength. You can use the prepared solution immediately after preparation.

Cooking options

A gypsum dry plaster mix can be made in different versions. There is a slightly different composition here and you need to choose the most acceptable one. Everything can be seen in the photo.

First option

To prepare a high-quality and inexpensive mixture, stick to the following proportions:

Plaster of paris - 3 - 4 bags;
Plaster mix, type ABS (Ekogypsum or Rotband) - 1 bag;
Small sawdust wood - 1 bag.

There is nothing difficult in preparing the mixture:

Those components that have been listed must be mixed in a dry state until a homogeneous mass is obtained. Then the mixture must be poured into polyethylene bags, it can be in other containers, and stored here.
Before using the mixture, it must be diluted with a little water. Mix well using a special mixer.
Factory plaster mixes contain special additives that help regulate the rate of drying of the solution. Thanks to this, working with plaster becomes easier and more convenient.
Sometimes it happens that a self-prepared solution sets too quickly. To prevent this from happening, add wallpaper glue to its composition.

Attention: It is very important that not every wallpaper glue can be combined with gypsum. I would like to recommend CMC glue - one of the proven options.

Slaked lime can be added to the plaster. Thereby. The material will become more plastic. Also, lime, which is used to create a solution, has bactericidal properties. Thanks to this, mold will never appear on the walls.

Second option

To prepare a high quality gypsum-chalk putty, you will need such components as a solution of wood glue (5%), the amount is determined by the consistency of the glue; one kilogram of gypsum and three kilograms of chalk.

The mixture is made in three stages. The first stage is grinding and mixing each component until a homogeneous mass is obtained. To do this, you can use the capacity. A volume of ten liters is quite suitable. And you will also need a hammer drill and nozzles.
First of all, you should mix the crushed gypsum and chalk. When you get a powder of a homogeneous mass, you need to add glue and mix again. You should get a mass, without pronounced seals, lumps, light gray in color.

Attention: I would like to note: putty prepared exactly according to the recipe will dry quickly. Therefore, glue must be added to the dry mixture as a binding agent. It is best to do this before applying to the surface.

If the mixture is prepared according to this recipe, then it should be used for finishing leveling, and not for roughing. The putty will be applied conveniently and simply (see How to putty the walls with your own hands, observing all the rules), if prepared correctly.

The third option

Thanks to this recipe, you can prepare a mixture with which you can finish the painted surface:

To do this, you will need: one hundred grams of NF-1 desiccant, two kilograms of gypsum and one kilogram of drying oil.
This putty can be used when finishing oriented strand board. To speed up the drying process, a desiccant can be used in this case.
In the process of preparing the mixture, instead of gypsum, you can use chalk powder. The proportions are the same. Thus, the mixture will dry more slowly, moreover, it will be able to retain its original properties.

Attention: I would like to give one piece of advice. When making plaster, do not forget about personal safety equipment. Use gloves, goggles and a respirator.

Fourth option

The consistency of lime plaster is similar to ordinary plaster... The only difference is that it dries meleno. Because of this, such a solution must be applied in a thin layer. It should be borne in mind that each of the subsequent layers must be applied only after the previous layer is completely dry.

To apply the solution conveniently and simply, you need to add gypsum to lime plaster... You get a lime-gypsum composition. Its layer dries on average in five minutes. Moreover, its hallmark is optimal adhesion.
To get a lime-gypsum mortar, you need to use three parts lime mortar and one part of gypsum powder.

The purchase of finishing materials has a significant impact on the cost of renovation works... You can save a lot of money if you prepare the plaster yourself. The dry gypsum plaster mix is not difficult to do and this will help reduce costs.

Dry building mixture is a multicomponent dry powder that, when diluted with water, turns into a plastic solution for the desired purpose. Gypsum-based mixes are lightweight and easy to work with. The disadvantages include only the possibility of using it only inside dry rooms.

Materials based on gypsum binders are characterized by high heat and soundproof properties, fire and fireproof, lightweight, can be used as decorative elements for architectural solutions for interior decoration. The use of gypsum materials for interior decoration provides a favorable indoor climate due to the ability of the material to "breathe" - it is easy to absorb moisture and release it. IN last years new generation materials have been developed based on gypsum binders: composite, modified, with reduced water demand and high performance properties.

The main components of gypsum dry mixes are: gypsum binders, fillers, functional additives. As a binder in gypsum mixtures are used plaster of paris based on b- or a-calcium sulfate hemihydrate. Less commonly, they are used in a mixture with anhydrite (especially for plastering works) to provide required time frame grasping. High-strength gypsum (a-hemihydrate) and anhydrite are used in self-leveling mixtures. The use of such types of gypsum binders in floor compositions is explained by the requirements for such mixtures and hardened solutions - the necessary vitality and high early strength, providing a short time walking.

Gypsum is a quick-setting and water-absorbing compound. In gypsum-based mixtures, polymers are introduced in order to reduce water absorption and increase adhesion, as well as inhibitors that slow down the gypsum hardening reaction. The inhibitors include, in particular, food grade or technical citric acid. If, when mixed with water for 1 kg of gypsum, add 10-20 grams citric acid, the gypsum mass will slow down its hardening up to 30-40 minutes.

The filler is introduced to prevent cracking during operation, to improve manufacturability during application. Quartz sand, as well as limestone flour, dolomite flour, chalk, and ash are used as fillers in gypsum mixtures. Perlite is used in the composition of lightweight plasters. Functional additives slow down the setting of the gypsum mixture, increase water retention, mobility, plasticity, bond strength, create a special pore structure, and reduce the risk of cracking. Set retarders provide an increase in the vitality of the mortar gypsum mixture. It is known that gypsum binders set quickly, and the solution to the problem of increasing the vitality consists in the correct choice of special additives - set retarders. Water-retaining additives are introduced into gypsum mixtures in order to increase water retention, adherence to the base, improve mixing, impart viscosity and plasticity to the mortar mixture. Dispersants (plasticizers) - additives that are absorbed on the surface of the particles of the mortar mixture, reducing the formation of lumps during its preparation. Blowing agents - additives used in plaster mixes to create a special pore structure of the hardened material.

Gypsum mixes are divided into gypsum fillers, gypsum plasters, grout mixes, gypsum-based assembly adhesives and gypsum floor mixes.

Plaster putties consist of a gypsum binder (we will call it gypsum, although a mixture of alpha-gypsum and anhydride is used in the production), quartz or lime filler, cellulose thickener and redispersible polymer. Gypsum putties are applied with a layer of 1 mm to 1 cm. Gypsum putties are distinguished by high plasticity and whiteness. Used for filling walls and ceilings indoors in dry rooms, with improved and high quality finish in the final application. Gypsum-based formulations are especially common today.

When working with gypsum mixtures, you need to know that gypsum is calcium sulfate. When painting a surface leveled with such a mixture, acid-resistant paints must be used. Do not forget about safety precautions: plaster, even in a small wound, causes unpleasant sensations.

Gypsum plasters- dry mixes that have gained particular popularity among builders. The mixtures are light, easy to use, do not shrink (unlike lime-cement-sand putties), quickly harden and have a high working capacity - from 30 minutes to 1 hour. Dry plaster mixes based on gypsum are intended for plastering walls and ceilings with different surface indoors with normal and high humidity (kitchens and bathrooms).

You can make a simple gypsum plaster yourself. The composition (10 kg of gypsum, 1 kg of slaked lime, 50 g of citric acid) is mixed with water and stirred until the consistency of thick sour cream.

The ready-made mixture can be used to close up the grooves, level the walls or ceiling. Industrial plasters also contain fractional sand, cellulose thickener and redispersible polymer. To give the plaster lightness and volume, light weightless sands are added to the compositions - expanded perlite or vermiculite. The average consumption of such plaster is 7 kg / m2 when applied in a layer of 1 cm.

Gypsum-based assembly adhesives. Dry gypsum mixes for installation works, which are used for gluing sheet and tile materials (drywall, mineral insulation, foam sheets). The composition is similar to the composition of tile glue, only gypsum, not cement, is used as the main component.

Plaster mixes for the floor. This group includes self-leveling (self-leveling) compounds for filling floors with different layers. Dry mixes for self-leveling floors have a more complex composition and include functional additives such as superplasticizers, hardening accelerators, defoamers. Gypsum-based compounds are mainly used for indoor screeds.

One of critical issues the building materials industry is the development of domestic production of effective building materials based on harmonious and balanced activities in relation to environment, saving material and fuel and energy resources, maximizing the use of local and technogenic raw materials.

In this aspect, building materials and products based on gypsum binders are promising. Gypsum binders and materials based on them have a number of valuable qualities. The production of gypsum binders is non-toxic, characterized by a low specific consumption of fuel and energy (approximately 4-5 times less compared to the production of cement). Gypsum materials have good heat and sound insulation properties, fire and fire safety, relatively low density, decorative properties.

In addition, the use of gypsum materials for interior decoration provides a favorable indoor climate due to the ability of the material to "breathe", easily absorb and release moisture. Research into the development of waterproof gypsum binders has broadened their potential applications. A new generation of binders based on gypsum binders, characterized by reduced water demand and high performance properties, have been developed.

Despite the undoubted advantages of gypsum materials and products over materials based on other binders, the scale of their use in Russia is currently significantly inferior to products based on cement base.

The range of gypsum binders produced in the country for construction works limited to stucco, produced in accordance with GOST 1 25-79 with a strength range from 3 to 7 MPa.

Anhydrite binder, which is very promising due to the low cost of raw materials and low investment in processing, has not yet found sufficient distribution. Such an astringent has the same positive properties, as other gypsum binders, and even surpasses in ultimate strength. It can be used for the same purposes as gypsum binder, including for the production of dry building mixtures.

Building mixtures made on the basis of gypsum or anhydrite binders are called dry gypsum mixtures (SGS).

A distinctive feature of mortars based on gypsum dry mixes, in comparison with cement slurries of a similar purpose, is an increased yield per unit mass of dry mix. The use of gypsum dry mixes for finishing provides a reduction in labor costs by more than 2 times, and the consumption of the mix is almost 2 times lower than that of a cement mix for the same processing area.

GHS are homogeneous bulk materials optimal composition, consisting of carefully dosed and mixed dry components - gypsum binders, fractionated fillers (fillers), pigments and modifying additives for various purposes.

In accordance with the existing classification, the GHS can be subdivided into the following main types:

plastering (including decorative and protective);
putty;
assembly;
adhesives;
trowels;
floor (leveling for the floor device).

Mixtures based on non-waterproof gypsum binders are used for interior decoration of buildings and structures with dry and normal room conditions, and SGS based on waterproof gypsum binders for finishing work in rooms with normal, wet and wet conditions, as well as for finishing building facades in accordance with the current regulatory documents SNiP 3.04.01-87, SNiP 2.03.13 - 88, SNiP P -3 - 79 *.

Plaster mixes

Plaster mixtures are mortar mixtures of non-water-resistant gypsum binders of B- or a-modifications, anhydrite or their mixtures, coarse-grained aggregate with a fraction of not more than 2.5 mm and special chemical additives for various purposes. Such mixtures are intended for rough leveling of surfaces by single-layer plastering of walls and ceilings with different kind surfaces (concrete, brickwork, cellular concrete, other rough and corrugated surfaces).

The most famous types of gypsum plaster mixes include: ROTBAND, GOLDBAND, GIPSPUTZ HP 100, MASHI-NENPUTZ MP 75, AKUSTIKPUTZ, TEPLON, SILIN, FARVEST-Gips, Gypsum white, Gypsum gray, etc. CONS.

Gypsum plaster mixes and solutions from them should be characterized by the following indicators:

bulk density of the mixture, kg / m3 -700 ... 1100;
water-solid ratio (the amount of mixing water required to obtain a given solution mobility) -0.5 ... 0, b;
solution processing time, min. -50 ... 100;
density of the hardened solution, kg / m3 -800 ... 1100;
compressive strength, MPa - 2.5 ... 7.0;
tensile strength in bending, MP - 1.5 - 3.0;
adhesion strength to the base (processed surface), MPa - 0.4 ... 0.7;
shelf life, months - 3 ... 6

The indicators of these properties depend on the area of application of the solution and its composition.

Putty gypsum mixtures

Putty mixtures are dispersed mixtures of non-water-resistant gypsum binders B-or a-modifications, anhydrite or waterproof gypsum binders (gypsum-cement-pozzolanic or composite gypsum binders), fine and finely dispersed fillers and chemical additives for targeted purposes.

Such mixtures are intended for thin and finishing alignment surfaces of walls and ceilings; for final preparation of concrete and plastered surfaces for painting or wallpapering; for facing and restoration work. They are used for sealing longitudinal and transverse joints between gypsum board and gypsum plasterboard during interior finishing work, as well as seams when installing gypsum tongue-and-groove plates. They have good adhesion to various materials and practically do not shrink. The advantage gypsum fillers is their rapid hardening, which allows further finishing work after several hours of hardening.

The most famous types of plaster putty mixtures include: UNIFLOT; FUGENFULLER; FUGENFULLER Hydro; FUGENFULLER GW; FUGENFIT; FINISHING; UNIS GSh; GSh Slide; UNIS Blik; P-16 MONOLITH; R-1 7 MONOLITH; GLIMS-Gypsum; PETRO-MIX SHG; SHGL; SHGS; ShGU; KREPS GKL, etc.

Gypsum putty mixtures are characterized by the following properties:

compressive strength, MPa - 4 ... 1 0;
tensile strength in bending, MPa - 2.5 ... 5;
shelf life, months - 3 ... 6

Dry gypsum mixes (assembly)

Mounting mixtures are mortar mixtures of non-waterproof gypsum binders of p- and a-modifications or waterproof gypsum binders (gypsum-cement-pozzolanic or composite gypsum binders) with a specially selected complex of chemical additives.

Such mixtures are used during installation internal partitions from gypsum tongue-and-groove plates; when cladding internal surfaces with gypsum plasterboard and gypsum-laminated sheets, as well as when installing foundations for floors made of gypsum-fiber boards.

The most famous types of gypsum assembly mixtures include: PERLFIX ("KNAUF"), GIPSOKONTAKT ("Bolars"), VOLMA montage (JSC "GIPS", Volgograd), etc.

The main physical and technical characteristics of some types of gypsum assembly mixtures are as follows:

bulk density, kg / m3 - 800 ... 950;
water-solid ratio - 0.4 ... 0.6;
solution processing time, min. - 60 ... 120;
density of the hardened solution, kg / m3 - 1300 ... 1350;
compressive strength, MPa - 4 ... 7.5;
tensile strength in bending, MP - 1.5 ... 5;
adhesion strength, MPa - 0.3 ... 0.7;
shelf life, months - 6

Floor dry gypsum mixes (leveling)

Dry mixtures for flooring are mortar mixtures of non-waterproof gypsum binders a-modification, anhydrite, estrich-gypsum or waterproof gypsum binders (gypsum-cement-pozzolanic or composite gypsum binders) and a special set of chemical additives to increase the plasticity of the solution while reducing the water content.

The most famous types of gypsum mixes intended for floor foundations include ATLAS SAM 200 mixes, Alfa-Pol S self-leveling composition, Fast-hardening floor (Prospectors), SV-210 floor mix (Bolars), etc.

Dry mixes for self-leveling floors are known as self-leveling compounds: Flisestrich FE 80, Flisestrich FE 50, Flisestrich FE 25, which are produced by KNAUF enterprises. The hardened solutions from these mixtures have high strength and practically do not shrink.

The main physical and technical characteristics of some types of gypsum leveling mixtures for flooring are as follows:

bulk density, kg / m3 - 600 ... 700;
water-solid ratio - 0.48 ... 0.6;
solution processing time, min. - 60 ... 120;
density of the hardened solution, kg / m3 - 1100 ... 1800;
compressive strength, MPa - 4 ... 10;
tensile strength in bending, MPa-2.5,., 5;
adhesion strength, MPa - 0.3 ... 0.5;
shelf life, months - 3 ... 6

Raw materials

For the manufacture of GHS, the following basic materials and additives are used: gypsum binders of the G4-G7 grades in accordance with GOST 125-79 (for plaster and putty mixtures in the production of finishing work):

high-strength gypsum grade not lower than I 3 in accordance with GOST 125-79 (for high-strength putties and compositions for installation work, as well as in compositions for self-leveling floor screeds); waterproof gypsum binders according to TU 21-0284757-1-90 (for dry gypsum mixtures used in rooms with wet and wet modes of operation, as well as for floor mixtures); anhydrite binders (from natural raw materials and industrial waste) according to TU21-0284747-1-90 (for plaster mixes and leveling mixes for flooring);
hydrated lime according to GOST 9179-77 (sieve residue 02 up to 0.2% by weight). Humidity up to 0.5% by weight (in plastering compounds and in compositions of self-leveling mixtures for flooring).

Fillers and fillers have a great influence on the properties of GHS. The choice of the grain size of the aggregates is determined by the type of gypsum mixture: quartz and limestone sand are used with a fineness of up to 0.8 - 1.0 mm. When selecting placeholders Special attention given to the granulometric composition: there should be approximately the same ratio of aggregate fractions.

The following aggregates and fillers are used in the SGS:

expanded perlite sand according to GOST 10832-91; residue on a sieve with a mesh size of 1.25 mm - less than 10% by weight. Bulk density - from 70 to 1 25 kg / m3; used in compositions of heat-insulating or lightweight plaster mixes;
expanded vermiculite sand according to the current normative and technical documentation;
quartz sands in accordance with GOST 21 38-91, the residue on sieve No. 05 is less than 10% by weight. Moisture less than 0.5% by weight; used in plaster mixes and leveling mixes for flooring;
mineral powder for asphalt concrete mixtures according to GOST 16557-78, sieve residue No. 0315 is less than 10% by weight. Humidity not more than 0.5% by weight; used in plaster and putty mixtures.>

Chemical additives for gypsum mixes must meet the requirements of GOST 24211 -91. These include the following additives:

Water-retaining ones based on cellulose ethers (methylcellulose brand MC-100 (Russia); ethyloxyethyl cellulose, EOEC (Sweden); sodium salt of carboxymethylcellulose, (CMC), (Russia).
Based on cellulose esters (methylhydroxyethylcellulose, (MHEC), (Germany, USA); methylhydroxypropylcellulose (MHPC), ( South Korea);
Air-entraining anionic surfactants (Russia, Germany); olefin sulfonate (FRG);
Thickeners based on starch ether (Russia, Germany); based on hectorite clays (Italy);
Plasticizing naphthalene-formaldehyde, for example S-3 (Russia); melamine formaldehyde (FRG); polycarboxylate (FRG);
redispersive polymer powders: based on vinyl acetate copolymers (Germany, Switzerland, USA, France); based on styrene butadiene latex (FRG); based on acrylate (FRG);
defoamers - additives that are hydrocarbons and polyglycols on an inert carrier (amorphous silica).

In the manufacture of GHS, it is of great importance right choice additives that regulate the beginning and end of setting, especially intended for the production of plastering works. In this case, it is necessary to take into account not only the type of gypsum binder, but also the pH-medium of the prepared gypsum solution.

For a neutral medium of a gypsum solution, citric acid, sodium citrate, polyphosphates, protein hydrolysates, gelatins - CMC (sodium salt of carboxymethylcellulose), glues of animal origin, a mixture of lignosulfonates can be effective set retarders. However, it should be borne in mind, for example, that retardan, being an active retarder for the setting of gypsum, is very well suited for putty compositions. At the same time, it is not effective enough for plastering compounds, because gives a short period between the beginning and the end of setting, which is undesirable in the production of plastering works.

For gypsum mortars with an alkaline medium, tartaric acid, as well as a retarder based on tartaric acid and plastretard, are effective set retarders.

For a weakly acidic environment, for example, in plaster solutions based on gypsum binder from phosphogypsum, hydrated lime and sodium tripolyphosphate are used as setting retarders.

To achieve the required retardation of the setting of the gypsum solution, it is advisable to use a complex additive. A typical example is the plastard - a mixture of citric acid with polyphosphates and gelatin.

To reduce cracking and shrinkage deformations, cellulose fibers are introduced.

Putty, grouting mixtures and gypsum adhesives differ from plaster compositions, both in component composition and in its dispersion. A feature of these compositions is that as a binder, stucco with a particle size of less than 0.1 mm is used, the filler is limestone, dolomite flour, chalk with a grain size of less than 0.1 mm. In this regard, the number of water-retaining additives increases to 0.5-0.8%, while in plaster compositions it is 0.16-0.3%.

Water-retaining additives based on cellulose ethers are of great importance in dry-chemical mixtures, including SGS. Studies have shown that due to the weak intermolecular interaction with water molecules, these polymers have excellent water retention ability. Each polymer molecule can hold up to 20 thousand water molecules. The energy of this interaction is comparable to the energy of evaporation and capillary diffusion into the base, which is an obstacle to the escape of water. In turn, this energy is somewhat less than the diffusion energy of water during cement hydration, which allows it to take this water.

In fact, the water in the solution is replaced by a homogeneous jelly-like solution of methylcellulose, in which particles of cement and aggregate are suspended. The high water-holding capacity of such a system contributes to the complete hydration of the cement and allows the mortar to gain the necessary strength even with thin-layer application. After the water leaves, the polymer in the form of the thinnest film remains on the surfaces between the cement stone and the filler, without affecting in any way mechanical characteristics hardened solution. Thus, the addition of a small amount (0.02-0.07%) of water-soluble cellulose ethers to cement-sand mixtures leads to a significant increase in the open time and allows the solution to hydrate evenly throughout the volume, and also provides a significant increase in adhesion to the base and improvement surface quality. The action of methylcellulose is similar in gypsum mixtures.

Dispersion powders, which, unlike water-soluble cellulose derivatives, when mixed with water, form not solutions, but two-phase systems consisting of polymer particles (based on copolymers of vinyl acetate and ethylene, vinyl chloride, styrene acrylate, etc.) dispersed in water ... The addition of these compounds to construction chemicals allows you to actively influence the characteristics of the final material and provides results that are unattainable when using only traditional mineral binders. The first attempts to modify cement mixtures with polymers consisted of adding to the mixing water a vinyl acetate dispersion known as PVA glue. In gypsum mortars, this application turned out to be very effective, while in cement mortars (due to increased shrinkage from the use of PVA), they quickly abandoned. The next step was the use of two-component compositions consisting of a cement-sand mixture prepared in the factory and a polymer dispersion supplied in liquid form, which are mixed at the construction site. Two-component solutions are still used, but the aqueous dispersion loses its properties when freezing, therefore, in the cold season, its transportation and preparation of the working solution cause certain difficulties. The beginning of the production of one-component dry building mixtures dates back to 1953, when the specialists of the Wacker company (Germany) managed to obtain a dry redispersible powder, which, after mixing with water, forms a two-phase system with the properties of the initial polymer dispersion.

Dispersions differ from methylcellulose in their mechanism of action. As it is consumed, the water is concentrated in the pores of the cement stone and the dispersion is concentrated there, forming "elastic bridges" that work in tension and bending incomparably better than cement. The combination of mineral and polymer binders makes it possible to produce construction chemistry products that not only have increased strength properties and improved adhesion (including to such "problematic" substrates as metal, wood, plastic, glazed tiles, etc.), but and controlled rheological (thixotropy, plasticity) and special (hydrophobicity, fluidity) characteristics. For example, leveling solutions for floors contain a combination of special dispersion additives with organic and synthetic plasticizers, the presence of which determines such specific properties of these materials as the ability to spread and the smoothness of the resulting surface. Dispersion modifiers included in adhesives for tiling, improve working conditions, extend the "life" of the mixed solution and increase the thixotropy (the ability to thicken at rest and liquefy with stirring) of the material. They help improve adhesion to difficult substrates.

The development of the formulation of dry mixtures is a complex and lengthy process that requires the participation of qualified personnel and the obligatory availability of a modern laboratory for research and testing of samples of solutions from dry mixtures, equipped with modern equipment.