Plaster mix on a cement, gypsum and lime basis: ready-made dry mixes, composition and proportions. Gypsum or cement plaster - which is better? Is it possible to add gypsum to the cement mixture

In the construction of dwellings, gypsum mixtures have been used for many centuries. Ancient civilizations left us many architectural monuments, which were widely used Construction Materials based on gypsum binders.

The use of compositions based on cement and gypsum is due to the mass of positive qualities that are characteristic of this particular group of binders. They practically do not precipitate during hardening, quickly gain strength when solidified, gypsum materials have impeccable sound-proofing and heat-resistant qualities, good fire resistance, and, most importantly, this is an environmentally friendly composition.

Low cost plaster

Especially important is the use of mixtures based on gypsum and concrete for Russia in the construction and decoration of buildings and structures because: the lion's share of all the planet's reserves of natural gypsum is concentrated on Russian territory; the price of manufacturing a gypsum binder is very low (5 times) compared to the price of cement manufacturing; energy costs in the manufacture of 1 ton of gypsum are 3-6 times lower than in the production of a ton of cement.

Why Should You Use Supplements?

Despite the age-old experience of application and the abundance of positive qualities possessed by dry mixes of concrete or gypsum, these finishing materials are used in Russia only for plasters and putties on premises. The reason for this was the low water resistance and low strength characteristics, since gypsum dissolves quite well in water, and when hardened, it has a high porosity. But, the solution to these problems was found. To eliminate such shortcomings, additives are used that, when interacting with gypsum, form compounds with lower solubility.

Modifiers

One of the ways to solve problems with the strength and water resistance of concrete and mortars based on gypsum concrete binders is the admixture of a special kind of impurities - modifiers.

Modifiers are a carefully selected combination of organic and mineral components, which are first subjected to special processing and optimized in composition. With the help of these dry modifiers, formations become more water resistant, a denser structure is formed. Thanks to such modifiers, the mixtures not only increased their compliance with sanitary requirements, but also significantly improved moisture resistance, and the speed of curing of materials increased.

Quality improvement

The combination of these properties provides the following benefits:

• the energy saving of buildings is increased due to a wide range of strength characteristics, water resistance and frost resistance;
• use materials based on modified gypsum not only as finishing materials in residential premises, in buildings for various purposes and number of storeys, in enclosing, load-bearing structures;
• no need to use heavy construction equipment;
• construction time is reduced several times, and the initial cost of construction is significantly reduced.

Application

To date, dry modified mixtures based on gypsum and cement are the most in demand compared to a number of other finishing materials. Dry modified mixtures are used in leveling walls, ceilings, flooring, in tiling, masonry work, and are also used not only for puttying and plastering, but also as tile adhesive, self-leveling floors, etc.

Thus, if we take into account the many shortcomings in the cement industry, and these are inflated prices for Portland cement, and the shortage of its supplies, then the use of mixtures based on gypsum and concrete with the addition of modifiers is the best choice in the range of finishing materials.

Finishing work on leveling surfaces is carried out various materials. Depending on the location of the surface, the purpose of the room, environment compositions with different properties are needed.

What kind of plaster better fit plaster or cement, should be decided in each case individually. Correctly chosen qualitative composition provide long service life and aesthetic appeal plaster finish. How to choose the right solution, what are the advantages and disadvantages of different compositions, we will consider below.

Types of compositions

The plaster solution has various areas applications. The most obvious are:

• surface leveling;
• improvement of heat and sound insulation;
• fire protection.

Modern construction market offers different kinds ready mixes for finishing of walls, ceilings, internal and external works. Plaster solutions are divided into 2 groups depending on the application layer:

• regular or basic coverage. It is used when carrying out rough work;
• decorative. Various mixtures to create a finishing finish.

The main way to classify plaster mixtures is the separation of solutions according to the constituent substance:

• cement;
• lime;
• clay;
• gypsum.

Of course, there are various modifications of the compositions, except for the 4 main ones. They are obtained by mixing the main components and adding various additives, additives and plasticizers.

Due to their practical properties, the most popular compositions are gypsum and cement plasters.

Characteristics of the cement mixture

It is difficult to overestimate the convenience and optimality of cement plaster; this type of solution enjoys well-deserved popularity among both experienced craftsmen, and for novice builders:

1. Coating strength. This is the main quality of cement plasters, the surface is resistant to mechanical stress and reliable.
2. Excellent adhesion. Cement mortars fit perfectly on almost any base, it is enough to treat the surface with a primer.
3. Moisture resistance. Cement plaster is not afraid of the effects of precipitation and high humidity, so they are often used in the repair of facades and surface finishing in specific wet rooms.
4. Price. This composition has a quite budget price tag compared to other compositions.

Given that this a budget option, you should not choose a solution based only on the cost of the goods: compare the material consumption and pay attention to the operational properties.

The main disadvantage of cement mortar is poor adhesion to wooden, plastic or painted surfaces.

Due to the serious weight of plaster, it is rarely used on ceilings.

For the same reason, the load on the walls of the building during finishing should be calculated.

The plastering process itself is quite labor-intensive, despite the fact that it takes place in several stages, each of which requires a pause in work.

In order for the plaster layer to be as durable as possible and serve for many years, you should follow some rules in your work:

• plaster the surface at a temperature of + 5 to +30 0 С;
• be sure to treat the surface with a deep penetration primer;
• to apply an additional layer, you should wait for the previous one to dry;
• conduct plastering work on construction beacons;
• do not take on large volumes if there is no experience in this area.

Gypsum-based mixture

Gypsum plaster mixture consists of gypsum itself and plasticizers. It is applied, as a rule, in 1 layer by hand or by machine. The scope of the gypsum solution is quite extensive, although it has limitations. This type of plaster is used when finishing:

• brick walls and concrete slabs;
• indoor dry rooms;
• for leveling the surface for gluing or painting.

Finishing the surface with gypsum mortar will eliminate the need for puttying work. Quality work with plaster makes the surface absolutely suitable for decorative finishing.

The advantages of working with this type of composition:

The material is warm and dries quickly, it takes a maximum of 3 days to complete the work.

To disadvantages gypsum plaster include the impossibility of using the solution in rooms with increased level humidity.

The price tag is slightly higher than that of cement mortars, which is offset by the fact that there is no need to use putty.

Preparation of solutions

It is not enough just to choose cement or gypsum plaster, for use it is necessary to properly prepare the solution. Each type of plaster has its own recommendations for the mixing process.

Bulk components of the cement composition are mixed in dry form. Sand and cement are poured in thin layers, and then mixed.

After the dry ingredients are thoroughly mixed, water is added to them. Now the liquid mixture is thoroughly kneaded.

You can also prepare cement-gypsum plaster. This solution will set much faster, drying time will be reduced. But at the same time, the strength of the layer will also change, it will become more fragile. For more information on how to make a mixture, see this video:

Gypsum mortars are kneaded within a short time. It takes no more than 5 minutes to prepare a working portion of the composition. Usually, a gypsum dough is first prepared, which is subsequently diluted with water to the desired consistency.

Finishing various surfaces plastering is one of the most critical stages. The subsequent durability and attractiveness of the decorative coating largely depends on how correctly the composition of the solution is chosen, and how well it is applied. Therefore, treat both processes carefully, carefully observing all the rules, both selection and installation. You will learn how to choose a solution and which one is better in this article.

Depending on the purpose of the solution, there are 2 main groups:

Important! Among the areas of application of plaster solutions different kind, there are several most popular solutions:

Popular types of plaster

On the modern market there are quite a lot of varieties of solutions for plastering walls and ceilings.

One of the main principles of classification is the type of the main substance, which can be:

Features of gypsum plaster

The initial mass of gypsum plaster is a powdered dry mix, which includes:

Application areas of gypsum plaster

Most often, walls are plastered with gypsum plaster and ceilings in the following cases:

Advantages and disadvantages of gypsum plaster

To understand why the use of gypsum plaster for finishing various surfaces is many times better than the use of other compositions, here are some significant advantages of this type of material:

Video

Watch the video, which clearly shows an example of wall decoration with gypsum plaster to understand how simple the technology is and what the result of the work is.

Characteristics of cement mortars

Cement plaster is used mainly when it is required to create the most durable and durable coating.

One of the most popular options is the composition of cement plaster from the following components:

The second version of the commonly used plaster has the following components:

Applications of cement mortars

The continued popularity of such solutions is ensured by the breadth of application possibilities with virtually no restrictions.

An excellent choice would be cement plaster during the following works:

Advantages and disadvantages of cement plaster

We note some undeniable advantages of cement plaster, which often lead to the fact that preference is given to this particular type of solution:

Among the shortcomings, we highlight the following factors:

Video

Watch the video instruction on the use of cement plaster in order to properly organize your workflow if you use such a solution.

Conclusion

Given all of the above, the conclusion from the above features of cement and gypsum plaster can be drawn as follows:

• gypsum plaster will ideal option in the absence of professional skills, in case of finishing living rooms in which it is planned to paint the walls or stick paper wallpaper or in a situation where repairs are required as quickly as possible;
• Cement plaster is great in almost any case where the surface quality is not in the limit category, but it will require the help of professionals when applying if your own skills are not enough to do this job.

Good plaster lasts for decades. Now gypsum mixtures have replaced cement finishing coatings. But not all plasterers refuse the usual materials. Let's look at the strengths and weak sides gypsum and cement mixtures and figure out which plaster is better.

Features of cement-based plaster mixture

The word "plaster" comes from the Italian term stuccatura, which denoted the finishing materials familiar to the Romans (lime, alabaster, gypsum). Under modern plaster refers to a hardened mortar intended for leveling walls. It is unambiguous to say which solution is better and which is worse. The composition of the optimal coating depends on many factors.

Plaster solutions have been used for thousands of years to decorate houses, apartments, building facades. The demanded finishing material has evolved along with humanity. In recent decades, when building and repairing houses, builders have mainly used cement coatings.

The mixture consists of cement (main component), sand (filler), plasticizers. As the latter, limestone, gypsum, or combinations thereof are used. Solutions are distinguished by the proportions of the components and depending on the surfaces to be finished. Coatings on cement base cover walls outside, inside buildings. Moreover, in the latter case, the premises may be unheated and with high humidity.

TO strengths cement finishing mortars include:

• universality;
• plasticity lasts for several hours - you can immediately prepare a large volume, spending it as needed;
• strength of the finishing layer;
• affordable price.

However, cement plaster is far from ideal. Masters note the following shortcomings:

• the mixture does not fit well on the concrete base:
• the layer dries for about 14 days, which reduces the pace of finishing work;
• high humidity when working with the mixture - for the crystallization of cement particles, the surface to be trimmed must be sprayed with water;
• the main component cement gives the finished surface an unsightly gray color;
• at the final stage, finishing puttying is mandatory;
• when working, a suspension of sand, cement, which enters the respiratory tract, rises into the air.

The main problem when working with cement coatings is a cracked finishing layer. In addition, as it dries, the composition will shrink, which will lead to irregularities. By the way, for this reason, it is not used for drying rooms. optional equipment(heaters, hair dryers, heat guns).

Thus, the cement finishing mortar is suitable for walls in technical rooms, facade works, in apartments with draft and.

Advantages and disadvantages of gypsum coatings

Despite all the advantages of cement mortar, with interior decoration gypsum plaster confidently competes with him. As the name suggests, the main component of the mixture is gypsum powder, made from a natural mineral. During the production process after a long heat treatment this powder is crushed. As a result, the finer the fraction (grain size), the better the treated surface.

In addition to gypsum, the composition of the solution includes natural or synthetic fillers, polymer additives. For leveling walls, the shape and size of the grains are of no small importance. In addition, fillers reduce the cost of the mixture and increase the strength of the finishing layer. And the polymer ingredients increase the adhesion of the solution, make it more elastic.

Based specifications finishing coating, its advantages can be distinguished:

• High adhesion - the solution falls on any base;
• Leveling ability - the surface finished with gypsum coating is immediately ready for painting, whitewashing, wallpapering;
• The consumption of this mixture is lower than that of cement. True, for this you need to follow the rules and technology of work;
• Solid thickness of the finishing layer - sometimes it reaches 6 cm;
• It is easy to work with the mixture - it fits well on the surface, leveled, smoothed;
• The surface treated with such plaster acquires additional sound and heat insulation qualities.

Despite all their positive traits, gypsum coating is not used everywhere. There are reasons for this:

• Price. Gypsum mixture costs 1.5–2 times more than cement;
• Strength. The surface plastered with gypsum coating does not withstand mechanical damage;
• The solution quickly seizes, therefore, in order to avoid overspending, it will have to be prepared in small batches;
• The need to use additional materials. For example, when processing a concrete surface, it is necessary to use primer solutions, and plastering metal surfaces without a waterproofing layer is unacceptable. In addition, for this decorative coating tiling is not recommended. On contact adhesive composition from finishing material ettringite is formed - a mineral that destroys gypsum.

The main disadvantage of such a mixture is the undesirability of using it for surface treatment outside the house.

Among plaster finishing coatings distinguish three types. The first is a fine-grained solution, it includes carefully ground sand. Such material is recommended to be applied in layers of 0.5–0.8 cm thick. For leveling, apply a second layer. The main area of ​​​​application is the decoration of ceilings.

Medium-grained gypsum mortar is the most popular and, as a result, widespread. It is the main competitor of cement-based mortars. Allowable thickness 5 cm.

Coarse-grained gypsum plaster is used to hide significant surface defects. As a rule, broken slopes are repaired with its help, facades are updated. By the way, in the latter case, the selected mixture must be checked for resistance to water. Sometimes, despite the claims of manufacturers, it is better to play it safe and apply protective layer.

Work with gypsum and cement plaster - a comparative analysis

The main factor determining which plaster is better and which is worse is the characteristics declared by the manufacturer. But along with them, secondary factors must be taken into account - ease of use, the need to use additional materials.

At first glance, the advantages of gypsum coatings are obvious - they are elastic, stick to any surface, and are easy to set. And the faster the layer hardens, the faster the work moves. But with insufficient skill, the prepared batch of plaster will dry out. It cannot be reused. In other words, the price of a mistake is an additional cost, and the cost of gypsum plaster is not affordable.

Cement plaster mortar dries for at least two hours, which allows you to cover in one go large areas. However, the adhesion of such a composition is lower and in some cases (ceiling, corners) the surface will have to be reinforced with a plaster mesh. On the one hand, this entails additional labor costs, on the other hand, the strength of such plaster is many times higher.

As you can see, the answer to the question of which plaster to choose will be ambiguous. For outdoor work the best option becomes cement plaster. And here gypsum mortar- a great option for working inside the apartment (with the exception of the kitchen, bathroom,). In rooms with high humidity, it will be necessary to cover the finished surface with varnish.

With the help of cement and other mortar mixtures, it is possible to produce not only building parts, but also many other products. For example, beautiful patterned tracks for suburban area, stucco bas-reliefs for the facade of the house, garden sculptures and decorative vases.

The list can be continued for a long time - there are many options. Therefore, let's talk in more detail about the production of architectural and artistic products from concrete, plaster and cement.

Cement

These mixtures are based on cement powder. As a rule, it is not used in its pure form, but diluted with pure river sand in a ratio of one to two or one to three. So it turns out sandy cement mortar.

In addition, aggregates such as peat and other materials can be used. All of them must be clean, without impurities. Plasticizers are added to improve plasticity. You can use PVA glue.

As for, depending on the purpose of future products, its various brands are used, which are produced a large assortment. For decorative purposes, in particular, white or colored cement is used, and if special strength is required, high grade material (M400, M500). In any case, fresh powder is required (the date can be found on the package), preferably this year.

You can check the quality and practical way holding a little cement in his fist. It should not gather into a tight lump.

Products made on the basis of cement mortars are strong, heavy, moisture resistant, long-lived. They can withstand atmospheric changes and can be constantly on the street. If it is necessary to obtain a colored mass, a coloring pigment can be added to the composition.

About what products can be made from plain concrete, this video will tell:

Cement-lime

For stucco work, it is advisable to use a cement mortar with the addition, which adds plasticity to the mass and makes it more convenient for the formation of products (they, by the way, are obtained in a lighter shade than pure cement). At the same time, lime paste is added to the concrete composition (no more than twenty percent of the cement weight).

Gypsum and gypsum concrete

It is characterized by low cost and almost instant setting, so it is convenient to work with it. Various figurines, stucco, vases are made from gypsum dough.

Distinctive features finished products brittleness and low water resistance. Therefore, in the case of external use, they must be covered with moisture-proof compounds (special varnishes, paints). The addition of PVA glue improves the quality of the gypsum mortar.

If aggregates are added to gypsum, in addition to water, it is called gypsum concrete.

• Various additives can be used organic matter- shavings, straw, sawdust, peat, reeds.
• Or mineral - for example, such as slag, sand, ash, pumice, gravel and gravel. They give higher strength characteristics than organics (with the introduction of which the compressive strength decreases).

If it is necessary to obtain a particularly strong and water-resistant mortar composition, hydrophobized gypsum or gypsum-cement-pozzolanic binder is used. And then we will talk about the options for preparing products from mortars.

Do you dream of making a decorative item from plaster, but do not know which idea to choose? Then watch this video carefully:

What can be prepared from such mixtures

Decor items

outdoor vases

These elements perfectly complement the territory. personal plot, serving both practical and decorative purposes. The following solutions can be used for:

• Cement-sand(from one measure of cement and three to five measures of sand).
• Gypsum- from gypsum powder and water (possible with the addition of PVA).
• - from a diluted ready-made dry mix (commercially available).

moldings

Columns and rosettes, cornices and architraves, bas-reliefs and pilasters - all these products can be made with my own hands using special molds for casting. The following types of solutions are used:

• plaster- appropriate for finishing ceilings, as well as for decorating facades. In the latter case, a waterproof coating is required. Or take a special hydrophobized gypsum.
• cement- often used for exterior finish houses.
• Polyurethane- sold in ready-made. Finds universal application. The products are light, durable, resistant to any atmospheric conditions.

garden sculptures

Fashionable and beautiful decorative elements. For their manufacture, sometimes quite a bit is required: a form from improvised materials, cement or gypsum, aggregates. Figures are made from gypsum, cement or gypsum-cement mortar (usually with the addition of PVA glue). Large sculptures require a frame or armature.

It is worth remembering that the metal fittings used in gypsum products must be covered with protective composition(not to oxidize).

Paths for a garden or cottage

Today it is customary not to make them solid, but to make them from separate curly tiles. For these tiles, special forms are produced (but you can make them yourself - forms for architectural and decorative items from concrete, gypsum, cement are described in special materials in this section).

The solution poured into molds usually contains cement, sand and gravel. If you want to make a color, the appropriate coloring pigments are introduced into the mixture.

Products for building purposes

Fences and poles

These elements must be strong enough, so they are cast from concrete (based on cement grade not lower than M400). Reinforcement made of metal bars or wire must be laid inside.

Artificial stone for masonry

For internal works used frequently gypsum stone- light and does not cause problems when fastening (it can be glued with almost any adhesive composition). For facade cladding, cement stone is often used, imitating natural (for which dye and natural stone chips are introduced).

Details of building structures

Panels, ceilings, partitions, floor slabs are also cast from mortar. If strength and water resistance are required, then a cement composition is used. The higher the brand of cement, the stronger the product.

Gypsum concrete is mainly used for interior parts. For example, cladding panels, internal partitions, ventilation ducts and various architectural elements (however, this is more likely to apply to stucco molding).

Technologies for the production of do-it-yourself products from concrete, gypsum, cement for construction and decoration with detailed photos and videos are described in more detail in the relevant articles in this section.

This video will tell you more about the preparation of gypsum concrete: