What is the composition of the mortar for plaster. Correct proportions of mortar for plastering walls. Buy a ready-made mixture or make it yourself

Cement-sand mortar, which is used to level walls and prepare for finishing, has many advantages.

Being budget option for repair work, it can even serve as a topcoat for external walls. In order to properly perform plastering, it is necessary to study the composition cement mortar for plastering walls and find out how to prepare cement-sand mortar for plastering walls with your own hands.

A little about the mixture

Today we will not only find out everything about cement mortar for plastering walls, the proportions of its production and the characteristics of the material, but also get acquainted with other popular plaster mortars. First of all, it is worth noting that plaster solutions are necessary for leveling the bases and preparing them both inside and outside the house. At the same time, for the street the mixture must be moisture-resistant, frost-resistant and resistant to sudden changes in temperature, and for the interior it must be plastic and environmentally friendly.

Plaster can be applied to concrete, wood, metal bases, as well as gypsum plasterboard, foam concrete or brick. In this case, you should start from the characteristics of the base and their adhesion to the solution. In the table you can see the most popular combinations of mixtures for surface treatment and their proportions in parts:

Cement plaster is usually used for wet rooms, facades, plinths and the foundation part on which the house stands. Various additives improve the characteristics of the material and make it insulating. A simple homemade recipe and ease of application makes it possible to process more area. In addition, you can mechanize the process of spraying on the wall.

Important! Costs for purchasing components and self-cooking solution will be minimal.

Mixing mortar for plaster (video)

Preparing the mixture

Self-production cement plaster consists of mixing all the necessary components and adding plasticizers to improve the quality of the mixture. The use of sand as a filler is traditional. Such a solution acquires the properties of strength and resistance to cracking, which is so necessary for the surface.

Important! All ingredients are important for the mixture, so when choosing cement, base it on its brand. Higher grade means better strength.

Let's find out how to properly make cement mortar for plastering walls yourself and learn tips from professionals:

• A novice master has no idea what cement brands mean. Therefore, when choosing them, proceed from the specifics of your work. At ordinary plaster M400 is suitable for walls; for work rooms, garages and where you need to save money, choose M300, but for the basement of a building and places with high humidity you should buy Portland cement M500
• The mixture begins to dry within 10-15 minutes after application to the base, so there is no need to hesitate when spraying and smoothing. It will take 10 to 12 hours for the plaster to dry completely. If you want to maximize the strength of the plastered wall, then you will need to exclude all additional finishing and mechanical influences for about a month
• You need to choose the right sand fraction for cement mortar - it can be from 0.2 to 0.5 mm and from 0.5-2 mm. Make sure that there is no organic impurity in the sand, otherwise it will cause rotting in the future

Table of proportions depending on the brand of cement:

Cement brands	Brands of solution
	200	150	100	75	50
300	-	1:2,5:0,1	1:3,5:0,2	1:4:0,3	1:6:0,6
400	1:2,5:0,1	1:3:0,2	1:4,5:0,4	1:5,5:0,5	1:8:0,9
500	1:3:0,2	1:4:0,3	1:5,5:0,5	1:7:0,8	-

Important! Using online calculator It will be easier for you to calculate the required amount of mixture for treating the wall surface. And with the help of the video, every beginner will learn the sequence of mixing plaster.

Most people are interested in how long it will take for cement plaster to dry on a wall? First of all, the drying process depends on temperature environment- For interior spaces It is prohibited to use artificial drying and allow drafts. For external walls It will take about 24 hours to dry, but the strength indicators will gain strength about a month after finishing. In what sequence to prepare cement plasters and how to make the correct solution yourself:

1. The main components in dry form must be taken in equal parts, then mix them well together
2. To improve the quality of the plaster, it is necessary to sift the resulting mixture through a sieve.
3. At the next stage, water is added to the mixture - the resulting solution should be homogeneous
4. Cement plasters are not plastic, so there is one trick in which washing liquids are added to the plasters at the rate of 30-50 ml per 5 liters of water

Plastering process

For quality implementation For repair work, you should have at least minimal plastering skills. Therefore, let's look at the features of plastering walls with cement mortar using beacons:

• For rooms, for example, in the bathroom, where you need to glue tiles, you need to achieve perfectly smooth walls, you should use beacons. The cost of such work will be slightly higher, since the purchase of metal beacons will be required
• First of all, it is necessary to install the outer beacons, which will be located at a distance of about 20-25 cm from the corner of the room. The strips should be fixed with plaster mortar cakes, which are 40 cm apart from each other.
• The next metal beacon is pressed tightly against the guides and checked with a building level. Next, a fishing line or rope is stretched between the vertical strips, thanks to which the fastening of subsequent beacons is controlled
• Don't forget to use a small ladle to spray the solution - more experienced craftsmen For this purpose, spatulas are used, which can be used to immediately level the surface
• After treating the entire surface, let it dry and then remove the metal beacons. They should be picked out only after the solution has set. The resulting voids should be plastered with finishing putty or plaster mortar for leveling
• When plastering brick walls cement mortar, it is good to use a reinforcing mesh, which is fixed with cement mortar. The liquid should have a dense consistency. For one square meter At least 8 fixation points must be used

Important! At quality leveling the wall will last for many years, it will not crack or crumble.

Mechanical Leveling Options

For those who are not confident in their plastering abilities cement mixtures interested in how mechanized plastering of walls using cement is performed sand mortar and what is the price for carrying out this work. It should be noted right away that many craftsmen charge for 1m2 of area, and total amount depends on the area of ​​the entire room.

The machine method of finishing surfaces significantly speeds up the speed of all repair work. The elastic mortar is thrown onto the wall using a hopper - it makes it possible to increase productivity. The table shows the average prices for professional plaster:

Name	Prices per m2
Plaster without mesh	From 450 rub.
Plaster on mesh	From 550 rub.
Arched slopes	From 660 rubles per linear meter
Plastering wall surfaces on beacons

Plaster mortar is an indispensable material for repairs, insulation, leveling and even decorative finishing various surfaces inside and outside the building. But for each type of work a certain composition is used.

For example, to align interior walls Lime mortar is excellent for plaster (see how to make it correctly) - the proportions and ratio of all its components can be different. What do they depend on and how are they selected?

Types of plaster solutions

First, let's find out what components can be included in protective and leveling mixtures, and what they are. The required ingredients are water and sand, which acts as a filler.

And the basic properties depend on the binders, which can be cement, gypsum, lime or clay. Their proportion for plaster relative to water and filler determines the quality of the solution.

Component Specifications

To understand why one solution is used for plastering the plinth, another for facades, and a third for interior walls, you need to know the properties of the materials from which it is made:

• Sand. It differs in the size of the fractions and the place of extraction. Pure river sand is considered the best for plaster, but it is also sifted before use to remove foreign matter and large particles.
• Cement. After hardening, it acquires high strength, resistance to water and weathering, and can withstand serious mechanical loads.

For reference. Cement happens different brands: 50, 100, 200, 300, 400, 500, 600, 800. These numbers indicate the resistance of the material to compressive force, expressed in kg/cm2.

• Lime. It can be slaked, quicklime, white, gray, etc. Durable, slow-curing material showing good operational properties in dry rooms. But it is not waterproof and does not withstand weather conditions well.

• Gypsum. A fast-hardening material with low strength and poor resistance to moisture - it quickly absorbs it, losing its properties. Can be added to lime to speed up setting, but is incompatible with cement.

Types of solutions

The composition of the plaster is selected depending on where and on what surfaces it will be used.

In this case, the above properties of the components are taken into account:

• Lime (see Prepare your own lime mortar for plaster). The proportions for the plaster solution depend on the fat content of the lime paste: add from two to five parts of sand to one part of it. First, mix these components in equal parts, then add water and mix until lumps are eliminated, after which, if necessary, add sand in portions to obtain a solution whose consistency resembles a viscous and thick dough.
• Lime-gypsum. In addition to sand and lime, it contains gypsum, which speeds up the hardening of the solution and complicates working with it, but the surface also gains greater strength. Gypsum is usually taken one part to five parts lime.

Advice. If you are going to plaster with your own hands, remember that this solution begins to harden within 5-6 minutes, so you need to prepare it in small portions and use it quickly.

• Lime-cement. Adding lime to cement mortar increases its heat-saving properties. The ratio of cement-lime plaster can be different depending on its purpose. These are listed in the table below along with the proportions for other plasters. But you should know that lime absorbs moisture from the solution, so to prevent it from drying out quickly, the finished surface must be covered with plastic film, otherwise cracks will appear on it.

Note. Lime significantly extends the setting time of cement mortar; it can remain viable for up to two days.

• Cement. This is the most commonly used plaster mortar, having a wide range of applications. It is used to decorate the facades and plinths of buildings, walls in utility rooms, as well as in residential buildings characterized by high or unstable air humidity (see Let's look at how to plaster with cement-sand mortar). It is worth talking about it in more detail.

What you need to know about cement plaster

The main thing to remember: the proportions of water-cement-sand in plaster depend primarily on the brand of cement. The higher it is, the less binder is required to prepare a solution of one brand.

As a rule, instructions for performing a particular type of work contain information about what brand of plaster mortar is required in a particular case. The highest M100 is obtained by mixing one part M400 cement and three parts sand. The amount of sand decreases with increasing grade of cement and increases with its decrease.

Since the price of high-grade cement is higher than low-grade, and sand is cheap or even mined independently on river banks, to reduce costs while maintaining the required quality of plaster, it makes sense to buy binder of the most popular brands M300 and M400, rather than spend money on expensive material.

Failure to comply with the proportions leads to changes in the properties of the plaster:

• If there is too much cement in it (greasy mortar), then when it dries it will shrink greatly with the formation of cracks;
• If you transfer sand (a thin solution), then most likely there will be no cracks, but the coating will not have sufficient strength.

How to properly prepare plaster mortar

Preparing plaster mortar is also not an easy task; it must be done according to the rules. If everything is clear with ready-made mixtures: they are simply filled with the required amount of water and mixed, then when self-production all wrong.

First you need to prepare the dry mixture itself, determining the proportions for plastering brick, concrete or other surfaces, taking into account their location (inside or outside, in a dry or wet room).

So:

• Dry ingredients are poured into a mixing container. It can be plastic, metal or wooden box with a flat, smooth bottom. Moreover, sand is poured first, and binders are placed on it in an even layer.
• All ingredients are thoroughly mixed using a shovel or trowel if the volume is small.
• Then the mixture is leveled and its color is observed. It should be uniform, without streaks or stains of binder.
• If this is not the case, continue stirring until an even color is obtained.
• Then the dry mixture is poured with water or milk of lime, allowed to absorb and mixed well. This can be done manually or using a construction mixer.

It is important that there are no lumps left in the solution, and no unmixed dry matter in the corners of the container. The viability of a solution depends on its composition. Cement-lime ones last the longest, while gypsum ones should be used as quickly as possible.

Conclusion

No repair or construction project is complete without building mixtures, and the most popular is plaster. If you know how to prepare it correctly, then you will not have problems with its application or quality. finished surface. To learn more about this topic useful information, we recommend watching the video in this article.

Plaster is the basis before the final decoration of the walls. Today, there is a wide variety of materials from which you can prepare a solution for plastering walls. And here it’s worth choosing which composition is better to make with your own hands? In order to avoid unevenness and lumps in the preparation of mortar for the wall, you need to follow some rules and proportions, which will be presented in this article.

Solutions options

When preparing to level the walls with plaster, you should prepare a special solution, which should basically contain two main components: binder and filler. Each one includes various materials, which are freely available in markets and hardware stores. If one of the components is not used, the solution will either be weak, or will not stick to the wall, or it will be impossible to level it. And if the proportion is incorrect, you can initially make an even coating, but later, after complete drying, cracks will appear on the wall. The main types of plaster for leveling walls, which you can do yourself, are:

The first is a solution, which in most cases is used for plastering external, facade walls and plinths. That is, the presented type of plastering and its composition is mainly used in places of constant humidity. Inside an apartment or house, it is great for bathrooms and toilets. If you cook a lot and often enough, then it will also be a good choice for the kitchen.

The second type presented in the list is mostly used for external plaster walls that are not exposed to moisture and humid air.

The third type is suitable for interior walls in all rooms, except those in which the air humidity level is quite high.

Quality of wall solutions

For getting flat wall you need to cook correct plaster. To get rid of unnecessary lumps, it is recommended to sift all components through a construction sieve. If this is not done, then after cooking, you can find a heterogeneous mass, and you will have to strain the entire composition with your own hands, such work is not easy and takes quite a lot of time, so before this process should not be brought up. This process is one of the points of creating high-quality mortar for walls. Among other points it is worth highlighting:

Additionally, solutions for plastering walls are distributed according to fat content. You can meet with high fat content, with normal and so-called skinny ones.

Plastering process

The normal fat content of the plaster will ultimately lead to perfect result, that is correct selection all components and consistency. If there is increased fat content after drying, the process of cracking of the plastered wall surface will occur. Additional defects will include shrinkage and the appearance of cracks. In the presence of skinny, a process of lack of strength occurs, which leads to its falling off when leveled.

It is quite easy to determine whether the wall mortar has been prepared correctly, because all you need is a spatula. The difference is determined by the degree of adhesion of the plaster to the spatula:

Characteristics and composition

Now we choose which composition is suitable for specific purposes.

Lime. Lime dough and sand are used, composition ratio 1:3. The dry mixture is mixed with water. With the right consistency, the end result should be like a thick dough.

Lime-cement. To give greater strength, you need to add a tenth of cement and mix. All lime-based solutions must be prepared and used within 2 days.

Lime-gypsum. The composition ratio is 5:1, add water and mix. It is necessary to take into account the fact of rapid drying - in half an hour you won't be able to work with it. But if everything is done correctly, the plaster on the wall will be super durable.

Lime-clay. The ratio is 1:1, an additional fifth of sand is added. Also has high strength.

Clay. First you need to prepare dough from clay. This is done by adding water. When obtaining clay dough, it is mixed with sawdust in a ratio of 1:3. Adding water and stirring is present in every solution. It has disadvantages in the form of fragility and instability to moisture.

Clay-gypsum. The proportion and subsequent actions are identical to the lime-gypsum composition. Only here the basis is clay dough.

Cement. Used to treat walls that are constantly exposed to moisture or steam, regardless of external or internal use. The proportion is either 1:3 or 1:4 with sand. The property of quick drying allows you to work with it only for 1 hour.

Cement-lime. To prepare it correctly, you should carefully monitor the balance of the composition. Materials used:

You can prepare such plaster for walls with your own hands in two ways:

Modern materials

Today, people have begun to give preference to special dry mixes that are produced on the basis of Portland cement and are considered to be of high quality. In addition to the direct base, they also have special additives that provide the solution additional characteristics in the form of: increased strength, ductility. Exists whole line advantages that come with such a dry mixture, which is not difficult to make. Among them are:

• easy application on the wall without using reinforced mesh, which significantly reduces material consumption.
• greater elasticity. After drying, it tolerates temperature differences and rapid climate change very well.
• allows air to pass through itself and has a fairly strong resistance to moisture.

There are also modified wall mixtures that were prepared separately in laboratories. This process was carried out to ensure that the ratios of all components were perfectly observed, which ultimately led to a perfectly prepared solution. As an addition, it can be noted that plaster can be produced in different volumes, that is, as much as is required in this moment without excesses, leftovers and shortages. Sometimes they even write on the packaging the words “pour water and get started.”

Now you know the basics, all you have to do is choose quality materials to prepare a plaster solution for walls with your own hands and enjoy the work. Watch the video to reinforce:

Most reliable way, with the help of which you can qualitatively level the walls, this is plastering. Plaster allows you to prepare the base of external and internal walls for finishing. Previously, to prepare a solution for plastering walls with your own hands, classic ingredients were used, mixed with water in the correct proportion. It was only cement and sand.

The modern market for construction and finishing materials is full of ready-made mixtures that just need to be diluted with water. However, the rules for mixing the mortar will vary depending on the composition of the plaster. How do cement, clay and lime mortars differ from each other, and how to mix them correctly?

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Plaster composition

Each plaster mortar has its own components, mixed in different proportions:

• clay and sand in a ratio of 1 to 2 (5) - the number of shares of sand depends on how viscous the clay is;
• a solution consisting of three components - clay, lime and sand - is mixed in a ratio of 1: 0.4: 4;
• plaster made of clay, cement and sand is mixed in a ratio of 1:0.3:4.

All listed species plasters are mixed with water, the amount of liquid directly depends on what viscosity you require.

What is required for work

To mix different plaster compositions, you will need one or more binders (cement, lime, clay or gypsum), a filler (usually sand) and water. When mixing all the ingredients, you should be guided by the exact ratio of the composition shares. However, this is not the only thing that needs to be taken into account: the quality of the plaster is influenced by such a thing as fat content. Most often this applies to lime and clay plasters.

In this case, the concept of “fat content” has nothing to do with its literal meaning: it is a parameter by which the amount of binder component is determined - sufficient or excessive. Based on fat content, plaster compositions are divided into three types - fatty, normal and thin.

• The disadvantage of greasy plaster is that it shrinks too much when drying, which leads to cracks on the surface.
• A solution that is too thin also becomes covered with cracks, but for a different reason - it does not adhere well to the surface and gradually begins to move away from the base.

It is difficult to determine the level of fat content of plaster by eye; this requires some experience. While mixing the composition, check how strongly the plaster sticks to the tool. The more the solution sticks, the fatter the plaster, but thin plaster, on the contrary, will stick very poorly or will not stick at all.

Cement mortar

To properly prepare a cement plaster composition, you need to perform several stages of work:

1. First of all, the sand is dried and sifted until there is not a single lump left in it. Important: reddish sand should not be added to plaster, as it is of low quality. If you don't want to bother with sifting, you can use quarry sand, it is already clean and crumbly.
2. The second and final stage is kneading. Pour cement and sand in a ratio of 1 to 4 into a container of a suitable size and mix thoroughly. To avoid the appearance of lumps, add water gradually. However, it will be extremely difficult to mix such plaster yourself if you need too much solution. For such volumes you will have to rent a concrete mixer.
   
   Important: to obtain high quality plaster, you must use cement of at least M400. With the use of cheaper and low-quality cement, the walls will simply crumble.

   Lime mortar for walls

   
   

   Making such plaster is somewhat more difficult than classic cement mortar. Lime plaster hardens much more slowly, so you will have to resort to some tricks.
   Important: only slaked lime is suitable for preparing lime mortar.
   Stages of work:

   1. Grind the lime so that the end result is a homogeneous mass without lumps.
   2. Add sand in proportions of 3 to 1 to lime.
   3. Mix the dry plaster thoroughly and begin gradually adding water until you get a solution of the desired thickness. The finished plaster should not be stored for more than a day - it will be unsuitable for further use.
   4. To make lime plaster harden faster and have better adhesion, a little gypsum should be added to it. But in this case, it is better to stir the composition in small quantities, since it will harden very quickly - almost instantly after application.

   Important: do not overdo it with the amount of water. Too much a large number of Liquids will only worsen the quality of the plaster.

   Clay plaster mortar

   
   

   No less often than lime and cement, natural clay is used. The main thing is that you should not buy liquid clay for plaster, because it will slide down from the wall over time. In order for the solution to be of high quality, you will need a large number of ingredients - clay, sand, cement and lime. Stages of preparation:

   1. Soak the clay with water for 6 hours and add regularly new water as soon as you see that upper layer began to dry out. The clay should be of medium thickness.
   2. Pour in pre-sifted or quarry sand in a ratio of 2 to 1. Sometimes the amount of sand needs to be increased to four parts.
   3. To strengthen the solution, add 0.2 parts of cement and mix well.

   Not all plaster solutions are suitable for outdoor work; some are used only for finishing indoor walls. The technology for using mixtures depends on their composition.

   Where is plaster used?

   
   

   Depending on the climate, humidity level, and location of application of the plaster, different solutions are used:

   • Lime and lime-gypsum plasters are best suited for leveling indoor surfaces. Such walls are literally “breathable” - depending on changes in humidity levels, they either store moisture or release it back. As a result, the microclimate in the room is constantly regulated and maintained at normal levels.
   • Cement-sand plaster is used for external finishing works, and is also used in rooms with too much high humidity- in the kitchen, bathroom, bathhouse, etc. Such plaster not only levels the surface of the external walls, but also holds them together, making them stronger. Cement-sand mortars are used for finishing stone fences and garages.
   • Pure lime plaster is well suited for treating window slopes; it is much more effective than cement plaster, since it has best parameters thermal insulation. For example: thermal conductivity lime plaster and cement are 0.86 and 1.3, respectively.
   • Clay plaster is often used to decorate stoves, pipes and fireplaces. In this case, the immediate space around the stove is plastered with a clay-sand composition, and the thermal surfaces are plastered with a solution of clay and lime.

   Preparing the surface for plastering

   
   

   Plaster of any type must be applied only to a previously prepared base, otherwise the results of the work will not please you - the plaster will fall off the wall or ceiling along with the decorative coating.

   • IN brickwork it is necessary to remove all protrusions from the seams, and the bricks themselves must be completely cleaned of dust, dirt and cement residues.
   • Before starting work, notches must be applied to the surface of the building blocks.
   • If there was previously plaster on the base, it needs to be completely beaten off or only the top layer removed - depending on the condition of the coating.

   Calculation of plaster consumption

   Before starting work, it is important to know exactly how much plaster mortar is needed - this will help save money by avoiding waste of material. There are two main factors that are important to consider when calculating the volume of plaster:

   • Curved walls. If it so happens that the walls in one room are different in length and width (and this is not uncommon, for example, in panel houses), they must be leveled, which will require a much larger amount of plaster mortar. You will also have to increase the volume of the mixture if there is a need to seal cracks and potholes.
   • The composition of the plaster itself. Since different mixtures have their own consistency, the consumption per 1 sq. the meter will be different.

   Plaster calculation method

   First of all, you need to determine the required coating thickness. You should first prepare the base by removing all parts that are not firmly attached or are crumbling. When the wall is ready, use a laser level and determine the level by placing beacons around the perimeter of the room. If you don’t have a laser, use a weight (an ordinary washer will do) on a strong thread. Next, measure the degree of deviation from the resulting line at 4 points, add the resulting data and divide by 4.

   
   
   Standard plaster mixtures are based on a layer of 1 cm per 1 square meter. meter. It is enough to calculate the area of ​​the walls requiring plastering. Multiply the resulting dimensions by the average thickness of the plaster calculated earlier. At the same time, always buy mixtures with a small reserve, since the actual consumption of plaster may differ from what you calculated. Buy a couple more packs, but no more.
   Some features of plaster mixtures:

   1. The lime composition is warmer and practically not susceptible to the appearance of mold and fungi.
   2. Cement plasters are moisture resistant and have great strength.
   3. Gypsum in lime mortars increases their strength and quality of adhesion to the surface, but greatly reduces the time of use.
   4. Clay plaster mortars are the least durable of all, but they can withstand very high temperatures very well.

   When carrying out finishing work, external or internal, be guided by the choice of plaster based on the highest priority qualities. Then the plaster will last a very long time, and over time there will be no surprises in the form of cracks or crumbling walls.
   

The main purpose of plaster is to prepare surfaces for finishing, that is, to eliminate defects and level walls. In addition, the plaster mixture can act as a decorative coating, depending on the components and application method. We will talk about how to prepare a solution for plastering walls, how to calculate its quantity and apply it correctly, as well as some of the nuances of this process.

Any plaster solution includes three main components - binder, water and filler. The binders are cement, clay, lime and gypsum, and they are often combined in different proportions. The filler is most often ordinary sand, but in ready-made factory mixtures it can be replaced with quartz and perlite sand, marble and granite flour, and stone chips. Additionally, plaster mixtures include modifying additives - coloring pigments, plasticizers and others.

Depending on the type of binder, there are several types of plaster compositions:

• cement;
• clay;
• limestone;
• gypsum;
• cement-lime;
• cement-clay;
• clay-lime;
• lime-gypsum.

Mixtures with two or three binders are called complex. In addition to the composition important role The ratio of components also plays a role - based on this, solutions are divided into fatty, lean and normal.

A solution with a predominance of the astringent component is considered greasy. During the drying process, such plaster shrinks and cracks, as a result, re-treatment of the walls is required. It is not difficult to determine the fat content of the working mixture: when stirred, it sticks to the trowel and remains on the walls of the container in a thick layer.

If there is an excess of filler in the mixture, it is a lean solution. It is almost not subject to shrinkage, does not crack after drying, but does not adhere well to the surface and has too low strength. It is enough to lightly hit the wall for such plaster to fall off. When stirred, the thin solution easily slides off the trowel, leaving virtually no trace.

A normal solution is moderately plastic, it is easy to mix, and if you put a little mass on a trowel and let it slide, a thin, uniform layer will remain on the surface. It is this composition that ensures maximum adhesion to the surface being treated and creates a durable, reliable coating.

Popular ready-mixes

Blend name	Characteristics	Price
	Moisture- and frost-resistant, does not shrink, and withstands weathering well. Can be applied in layers up to 30 mm without reinforcement. Solution proportions: 0.16-0.2 liters of water per 1 kg of dry mixture. The solution consumption for a layer thickness of 5 mm is 6-8 kg/m2. The viability of the finished solution is 2 hours. Packaged in 25 kg bags.	From 280 rub.
	Frost-resistant, easy to apply, can be used for external and internal walls. Solution proportions: 0.3-0.42 l of water per 1 kg of mixture. With a layer thickness of 5 mm, the consumption is 9-10 kg/m2. Packing – 25 kg bag.	From 240 rub.
	It has increased resistance to low temperatures, is moisture resistant, very plastic and easy to apply. The proportions for mixing the solution are 1 liter of water per 4 kg of mixture. Consumption for a thickness of 2 mm – 2.5 kg/m2. The viability of the solution is 3 hours. Drying time is from 2 to 7 days.	From 360 rub.
Cement plaster "Starateli"	Waterproof, flexible, easy to apply. Forms a durable coating that is not prone to cracking and shrinkage. Mixing proportions: 0.26-0.28 liters of water per 1 kg of mixture. Solution consumption – up to 2 kg/m2. Packaged in 25 kg bags.	From 188 rub.
	The basis - white cement, filler – marble chips. It is resistant to moisture, low temperatures, does not shrink, and is easy to apply. Mixing proportions: 0.18-0.2 l/kg. The viability of the solution is 1 hour. Packaged in 25 kg bags.	From 423 rub.
	Color mixture on cement based, filler – quartz sand. Possesses water-repellent properties, well tolerated low temperatures, does not fade for a long time. Mixing proportions: 7.5 liters of water per 25 kg of mixture. The viability of the solution is 1.5 hours. Packaged in 25 kg bags.	From 340 rub.

Prices for popular types of plaster

Plaster

Proportions for preparing solutions yourself

Each type of solution has its own characteristics that must be taken into account when choosing plaster composition for finishing the facade.

Mixture type	Characteristics	Component ratio
	Suitable for both external and internal surfaces. It is durable, has good moisture resistance, and is easy to apply. The prepared solution should be used within an hour. When treating a facade, cement mortar is usually applied in 3 layers, and the proportions for each batch are different.	1 layer – 1 part cement and 3-4 parts sand. 2nd layer – 1 part cement and 2-3 parts sand. 3rd layer – 1 part cement and 1.5-2 parts sand.
	Adding lime allows you to increase the adhesive properties of the plaster and extend the hardening time to 48 hours. When kneading, it is not the lime itself that is used, but lime dough, which is prepared in advance.	1 layer – 1 part cement, 0.4 parts lime and 3-5 parts sand. 2nd layer – 1 part lime and cement, 2.5-3 parts sand. 3rd layer – 1 part cement, 1.5 parts lime and 3-4 parts sand.
	Clean lime mixture It is almost never used for plastering facades, with the exception of adobe houses. This coating does not have the required strength and does not tolerate excessive moisture, but it has high adhesion and antiseptic properties.	1 part lime and 3 parts sand.
	Such solutions are used, as a rule, for plastering walls made of adobe and wood. They are considered the cheapest, environmentally friendly, and the finished solution is suitable for use for several days. But at the same time, clay plaster is too fragile, afraid of moisture, damaged by fungi and insects	1 part clay and 3-5 parts sand.
	Plaster made of clay and cement has good strength, tolerates slight increases in humidity, and does not require large preparation costs. The time for using the finished solution is reduced to 1-2 hours	1 part cement, 4 parts clay and 6 parts sand.
	This mixture is very plastic, easily adheres to any surface, and after drying it forms a durable coating with antifungal properties. It is used for facades in areas with dry climates because it has low moisture resistance. The finished solution should be used within 3 hours	1 part lime and clay, 5 parts sand.

The indicated proportions may vary slightly depending on the humidity of the sand, the viscosity of the clay and lime paste, and the air temperature. Sand for mixing must be sifted to remove foreign particles. The clay must also be clean, without any remaining grass, pebbles or soil impurities. All this reduces the quality of the plaster. Ready-made factory mixtures have a balanced composition; you do not need to add anything to them except water. The proportions of the dry mixture and water are always indicated on the packaging, so read the instructions before preparing the solution.

Calculation of the amount of plaster mixture

Before proceeding directly to kneading, you need to calculate required amount solution. As you know, an unprocessed solution is unsuitable for storage, and all that remains is to throw it away, which means that part of the money will be wasted. Let's take a closer look at how to avoid unnecessary costs.

The greatest difficulty in calculations is the curvature of the walls. It is impossible to achieve a perfectly flat surface when building a house, and it is good if the deviations do not exceed 10 mm. But, as practice shows, very often the differences range from 1 to 5 cm, and in some cases even more. When plastering the entire house, calculations must be performed for each wall separately. First you need to determine the average thickness of the plaster layer.

Step 1. The surface of the wall is thoroughly cleaned of the old finish, all noticeable bumps are knocked down, mortar deposits are removed, and the seams are cleared if necessary.

Deep recesses and cracks in the wall are sealed separately with cement mortar and allowed to dry thoroughly.

In a small container, dilute alabaster with water to a thick paste, then apply a level to the wall, determine the vertical and throw the solution along this line at 3-4 points.

Apply the beacon, pressing it into the solution, and check its location with a level. If necessary, press in more or add alabaster. Other beacons are attached in the same way in 1.5 meter increments along the wall.

Some builders use special beacon fasteners with dowels instead of mortar, but for this you will first need to make markings on the wall and then drill holes along the lines. It is easier and faster to work with the solution.

Step 3. The width of the gaps between the wall and the beacons is measured, and then everything is summed up and divided by the number of beacons.

For example, at one point the gap is 2 cm, at another 3.5 cm, at a third place it is generally 5 cm. The more measurements you take, the more accurate the result will be, so measure the deviations under each beacon at several points. Let’s say the total is 30 cm, and there are 10 beacons installed. Divide 30 by 10 and get 3 cm - this is the average thickness of the plaster layer required to calculate the amount of mortar.

Step 4. Now let's find out the total volume plaster mixture: to do this, multiply the surface area by the layer thickness. For example, the width of the wall is 4.5 m, the height is 2.5 m, the thickness of the plaster layer is 30 mm (0.03 m).

5x2.5x0.03= 0.3375 m3

We round up and get about 340 liters of solution. With a ratio of 1:3, the volume of cement is approximately 112 liters, or 0.1125 m3. Average bulk density cement is 1500 kg/m3, therefore, by multiplying the volume by the density indicator, we find out approximate weight material: 0.1125x1500= 168.75 kg.

Since cement is packaged in bags of 50 and 25 kg, you will need to buy 3 large bags and 1 small, or 7 bags of 25 kg. The weight of sand, gypsum, lime and other materials is calculated in a similar way.

When using factory mixtures, it is easier to perform calculations. The packaging indicates the composition consumption per square meter at a certain layer thickness. If this thickness coincides with the one you got, you just need to multiply the indicated consumption by the working surface area. If it doesn’t match, multiply the consumption by the area and the layer thickness.

For example: on the packaging of the Weber Vetonit mixture the consumption is indicated at 2.5 kg/m2 with an application thickness of 2 mm. Our calculated thickness is 30 mm, that is, 15 times more. We calculate how much mixture is needed per 1 square meter:

2.5x15=37.5 kg/m2

Let's say the wall area is 10 m2, then for plaster you will need 375 kg (37.5x10). The standard packaging is 20 kg, so we divide 375 by 20 and get 18.75 bags. This means that for plastering you need to buy 19 bags of the mixture.

Solution preparation technology

Cement-sand mortar

Cement plaster is considered the most the best option for finishing the facade. The most commonly used is simple cement-sand mortar, a little less often - with the addition of lime or clay. For mixing, you need a container: it can be a special wide box or trough, and if the volume of work is large, then it is better to take a concrete mixer.

Prices for concrete mixers

Additionally, you will need a shovel and a measuring bucket.

Let's consider a step-by-step preparing a solution for three-layer application of plaster.

Builders call the first layer spray or spray. The consistency of the solution should be slightly liquid in order to easily fill all the pores on the wall surface. The application thickness does not exceed 4 mm. The proportions are given for preparing a solution from one bag of cement (25 kg). It is recommended to use cement grades M400 and M500.

Step 1. 6 buckets of sifted sand (10 liter bucket) are poured into the container, and cement is poured on top.

Mix everything well with a shovel.

Step 2. Pour in 15 liters of water and begin to stir vigorously, breaking up the formed lumps. The mass should become homogeneous.

Step 3. Add another bucket of water and mix the solution as thoroughly as possible to remove even the smallest lumps. After this, you can begin applying plaster.

The primer layer is applied after the spray has set, but before it has completely hardened. The application thickness should not exceed 15 mm if the plaster is performed without mesh reinforcement. The consistency of the solution is much denser and resembles stiff dough.

For mixing, take 25 kg of cement, 75 kg of sand (about 5 buckets), 17-20 liters of water. The components are mixed in the same order, but added together with water liquid soap– approximately 1 teaspoon per bucket of cement. Many people add PVA glue, detergent for dishes, antifreeze to increase the frost resistance of the coating. Only purchased plasticizers can be used. These additives are not mandatory components, but they significantly improve the quality of the plaster and make it easier to apply.

The third layer is called covering, and sand of the finest fraction is used to mix the solution.

The layer thickness should not exceed 3 mm. Professional builders recommend adding finishing layer lime dough, thanks to which the mixture becomes very plastic, easily rubbed, and does not shrink.

Cooking proportions:

• cement – ​​25 kg;
• fine-grained sand - 100 kg (about 6.5 buckets);
• lime dough – 56 l;
• water – 25 l.

If you have a concrete mixer, the mixing process occurs differently: first, 2/3 of the required amount of water is poured into the concrete mixer, then cement is poured in, and mixed for 2-3 minutes. Next, add sand, add the remaining water and stir again for 3-4 minutes. If lime is used, it is added at the same time as cement.

Preparation of lime dough

Lime dough should be prepared at least two weeks in advance plastering works, or even better – in a month. Right slaked lime can be stored for a very long time and used as needed.

Step 1. For extinguishing you need a deep metal container without traces of corrosion. When mixing lime with water, a lot of heat is released, the temperature can reach 100 degrees or higher, so containers made of plastic, especially thin ones, are completely unsuitable. So, they fall asleep inside lump lime and pour cold water at the rate of 1 part water to 2 parts lime.

Important! Quicklime is a very caustic substance, so you need to work with it in protective gloves and a respirator. Avoid contact with skin and mucous membranes - this will cause severe irritation.

Step 2. Use a shovel or wooden stick to thoroughly mix the contents of the container to speed up the hydration process. Depending on the composition of the lime, slaking can take from 8 to 30 minutes. As steam formation decreases, the mass is stirred again, and so on several times.

Step 3. After the reaction stops, the lime is mixed again, cover the container with a lid and leave for 2 weeks. The mass becomes plastic, all lumps dissolve without a trace and it can be added to plaster solutions.

For large volumes of extinguishing work, dig a hole at least 1 m deep, pour lime into it and water it with a hose. When the mass stops boiling, pour a thick layer of sand on top and cover the pit with boards or wooden shield. After 15-20 days, the lime dough can be used for its intended purpose.

Clay for mortar

To mix the cement-clay mortar, the clay is prepared in advance. It must be well soaked, otherwise the quality of the plaster is very low. Since it is much more difficult to sift dry clay than sand, before soaking it, simply remove all the debris, blades of grass, and large stones from it with your hands, and before mixing the solution, strain the clay dough through a sieve.

Step 1. Pour 1 part of clay into a wide trough or solution box and pour it in 3 parts cold water. Stir with a shovel until the clay is thoroughly wet, and leave for at least 5 hours, or better yet, for a day.

Step 2. When the clay is completely soaked, mix it again and knead the remaining lumps with your hands.

Step 3. When mixing cement mortar, clay dough is added after mixing sand and cement if the work is done manually, and together with cement if the mortar is prepared in a concrete mixer.

Factory plaster mixtures

Everything is very simple here. For kneading you need clean containers, water and construction mixer. Read the instructions on the package, take the indicated volume of water and pour into the container. Now you need to pour the dry mixture from the bag into the water and use a mixer to bring the mixture until smooth. After this, you need to leave the solution for 5-7 minutes ( exact time written on the packaging). Then mix again and plaster the surface.

Prices for mixtures for leveling walls and ceilings

Mixtures for leveling walls and ceilings

Video - How to prepare a solution for plastering walls