Types of building mixtures for outdoor work and water resistance. Dry mixes for external plaster. Cement-sand, cement-lime, decorative polymer, silicone and silicate, heat-saving compounds

Facade plasters are very popular for exterior decoration of residential buildings, industrial facilities and public buildings. The coating is not only aesthetic, but also durable. This combination of practicality and beauty, as well as a huge variety of design options, make plaster mortars very popular.

Plaster must not only withstand all the vagaries of nature with dignity, but also reliably protect walls and external insulation from their harmful effects. Hence the basic requirements:

1. Hydrophobicity - should not be destroyed by moisture or absorb it.

2. Insulating properties - participates in the preservation of heat in the house and partially prevents the penetration of noise.

3. Frost resistance - compositions that can safely endure at least 30 freeze-thaw cycles are suitable for exterior decoration.

4. Plasticity - first of all hides wall irregularities and other defects.

5. Adhesive properties - so that the coating does not peel off from the substrate, it must adhere well to the surface.

The advantages of plaster compositions for outdoor work include the possibility of application to insulated facades, thereby providing reliable protection of heat-insulating materials. The main disadvantage of facade decoration is, oddly enough, its unpredictability. The end result will depend not only on the quality of the solution, but also on many other factors: the preparation of the base, the technology chosen, the weather conditions during the work, the knowledge and experience of the master.

Classification by purpose

Depending on what goals need to be achieved with the help of plaster, it is conditionally divided into two groups:

• Starting - performs the functions of a rough leveling compound, used to seal seams, cracks and chips. To obtain a flat and smooth surface in the starting solutions, fillers of the smallest fractions are used.
• Finishing - is an external coating that performs both protective and decorative functions. The most popular in this category is the textured bark beetle, and the most economical is the traditional fur coat.

Most solutions can simultaneously act in both roles. But to reduce the cost of facade finishing, it is better to buy two different mixtures, choosing them in the line of one manufacturer.

Varieties

Depending on the binder taken as a basis, there are several types:

1. Mineral.

It is made of cement, which provides the facade coating with excellent performance: strength, water resistance and durability. Since cement mixtures do not have sufficient plasticity, various plasticizers are added to them to work with external surfaces.

The cement mortar can penetrate deep enough into the thickness of the base, especially if the first layer is applied by spraying. This property allows him not only to be securely held on the wall, but also to further strengthen it.

Mineral facade plasters for outdoor use have good air permeability, which is extremely important for buildings made of "breathable" materials. They also compare favorably in price - despite the high consumption (18-20 kg / m 2), the cost of cement mortar is much less than polymer compositions.

The disadvantages include only a meager selection of shades, so to obtain a decorative coating, you will also need to purchase a decent amount of silicate paint. Durability is relatively low - only 10 years, during which cracks will still appear on the surface of the finish.

The best facade mineral mixtures for today are produced by:

• Bolars based on white cement.
• Ceresit - sets the tone in the production of cement mortars with the Bark beetle effect.
• Knauf - for some time now, the company has also joined the production of outdoor finishes (Unterputz and fiber-reinforced Sokelputz).

2. Acrylic.

Very flexible plaster based on water-soluble polymer resins, which has good resistance to temperature extremes and UV rays. Special biocidal additives are also introduced, which prevent the growth of mold fungi and microorganisms on the facade. You can buy it in the form of a ready-to-work composition in the product line of Ceresit, Weber and other well-known companies.

The service life is at least 15 years, but under normal operating conditions it easily increases to 25. This is a very reliable coating that is not subject to cracking and has high mechanical strength. It is electrostatic and attracts dust, but care does not cause any special problems, since the dirt sticks, but is not absorbed - it is simply washed off with water, and the bark beetle is removed from the texture with a soft brush.

Sometimes there are problems in the process of applying the acrylic solution, as it seizes immediately. Mass-dyed plaster after a break in work at the border will differ in color. Therefore, everything must be done quickly, completely covering the surface of the wall from corner to corner.

3. Silicate.

It is made of liquid glass - an effective waterproofing material. At the same time, silicate facade plasters “breathe” freely, but have an average plasticity. The last property of the silicate solution during solidification often leads to the appearance of microcracks on the surface.

Like the mineral, the silicate mixture additionally strengthens the base, but this is already due to the chemical reactions of potassium glass. Therefore, it is great for walls made of fragile materials (aerated concrete, silicate blocks or shell rock).

An unpleasant property is a change in color when wet, although the shade is restored as it dries. They are quite capricious in application. For work, you will need a special silicate primer, as well as the ability to plaster quickly and efficiently, since the solution does not “live” for long.

4. Silicone.

The most expensive and practical. These universal mixtures are suitable for outdoor and indoor use, as they have excellent performance characteristics, an extensive palette of light-resistant colors and are completely safe. Another plus is easy application, so that everything can be done by yourself, saving on the services of masters.

The main advantages of silicone coatings include their antistatic and dirt-repellent properties. And the viscous base allows not only the plaster itself to reliably adhere to the load-bearing wall, but also to retain aggregate particles of any size. That is why it is most often found in the form of a decorative structural composition such as bark beetle or lamb.

Silicone plaster is not only very expensive in itself, it will also require an equally expensive primer on the same basis. But the resulting coating will faithfully serve for more than a dozen years without losing its original appearance.

These compositions must have maximum resistance to all adverse environmental phenomena, since they are the first to take a "hit" from the outside. It also requires external attractiveness. For such a coating, complex solutions are made with various fillers that give the original texture. But the most luxurious effects are obtained when embossed patterns are superimposed on a smooth surface.

Since plaster is expensive, it is necessary to minimize its consumption. To do this, the walls are leveled to perfect smoothness using a cheaper starter mixture. After that, the decorative composition is applied in a thin layer - about 5 mm.

Characteristics of mixtures

For walls made of lightweight building materials with very high vapor permeability, the exterior finish of the house with plaster should have the same high performance. Therefore, buildings made of gas silicate blocks and cellular concrete are best lined with silicate solutions.

Pebble or texture compositions with a "lamb" effect are best used on surfaces that are destined to stand for a very long time without refinishing. The reason is that the designated “make it and forget it” types of coating last for decades, and it is long and difficult to dismantle them.

Not all plaster mixtures can boast of color fastness, so before choosing a plaster, it is worth considering the location of the house. On facades exposed to sunlight, light shades are used. Too dark surfaces in such conditions will absorb heat energy better, lose their original attractiveness faster and may even crack.

For old buildings in need of exterior wall restoration, silicate mortars are best suited. But if funds allow, you can use silicone.

If fine-grained plaster is required, it is better to refuse cement compositions. A suitable option is easier to find in the range of acrylic mixtures.

Finishing the facade of a building is always a responsible and serious job. And the exterior wall decoration is a double responsibility. Because indoor temperature, climate, humidity levels are usually predictable, but not outside.

Only one thing is predictable from the outside - that it will be “harsh” and with constant changes in atmospheric conditions. And this means that the quality of work on the facade should be subject to increased requirements.

Of course, that compliance with the rules of technology is the key to success, but this factor is not the only one. In order to get a good result, it is important, first of all, to be able to purchase high-quality and optimally suitable for a particular region, project, plaster dry mixes for outdoor work.

If you manage to get good material, then the work will be argued.

In this article, we will talk about how to choose such mixtures, and what they generally are. Also consider a few nuances, because of which the choice may be complicated.

Let's start with the most important.

Where to buy plaster: in the market, in the market or from a private trader

It is no secret that today such goods can be purchased at a variety of points - both in a specialized store and "in the garage" from a private trader on a nearby street.

Let's look at the pros and cons of all options.

1. Construction supermarket. The option is good, because the assortment is large, and the goods can be returned if something happens without any problems - the main thing is that you keep the check. In most cases, reputable stores do not sell defective mixtures, but a poor-quality batch can still be caught.
   Of the minuses - there may not be such a store in your area, which means you will have to overpay for delivery or, at least for gasoline. In addition, the price of materials in such shopping centers, as a rule, is also not the lowest.

1. Market. A definite plus is that such a place is probably nearby. The second point is quite attractive and affordable prices. Among the shortcomings, one can single out the fact that it is unlikely that the same seller will have a large batch at once.

1. Private traders. Typically, such points are equipped for the sale of mixtures and other materials in the most ordinary garages on the streets of the private sector. The advantage here is that it is close, inexpensive, as a rule, the goods are constantly “fresh” and can often be borrowed.
   There are also disadvantages - in most cases, at such points, goods of unknown origin are packaged right on the spot. Most often, there can be no talk of any certificates of environmental safety.

Note!
Regardless of where you buy plaster, ask where exactly and under what conditions it is stored.
It is quite possible that the bags with the mixture just lay on the street under a canopy for about half a year.
And in this case, the material could easily become damp and lumpy.
The room in which such goods are stored must be dry, ventilated and relatively warm.

Consider the following, no less important point.

Buy pre-mixed or make your own

In fact, everything is quite simple here.

Very often, if a large amount of plaster mixture is required to complete the work, foremen think about buying the necessary components in bulk and then mixing them with their own hands.

At first glance, this makes sense - it turns out cheaper.

However, this is only at first glance...

Firstly, not much and cheaper, if you count carefully. Because you still have to pay not only for buying a pile, but also for packing by workers, for buying bags for this very packing, for mixing materials. Not to mention that all this needs to be stored somewhere, and stored correctly!

In addition, it is not a fact that with self-preparation, a dry plaster mixture for outdoor work will turn out to be better. Here, after all, clear proportions must be adhered to, and the presence of impurities should be excluded. In the factory, this is much easier to control, you see.

Pay attention to the fact that in the case of self-mixing of the components, the speed will drop.
After all, time will be spent not only on the main task.

In general, if you approach the issue objectively, it turns out that it is easier, faster and more efficient to buy ready-made plaster dry mixes for outdoor work.

But the choice, of course, is yours.

Now let's delve a little into the topic - let's figure out in detail what kind of mixtures of this type actually are.

Overview of plasters

Before starting, it is worth noting that we will talk about the most popular materials that can be bought in almost any more or less large city.

We will not consider some very “exotic” mixtures and those that are “just a month since they were invented”.

So let's start the review.

Cement-sand mixtures

In fact, this is the most common, so to speak, "classic" plaster, which has proven itself well as with.

The composition of the mixture is very simple:

• cement;
• sand;
• water.

The material fits perfectly on the surface of brick and concrete walls, and also has a long service life. For example, in the private sector, where there are old houses, many facades on them have been regularly serving for more than a hundred years.

The advantages include the fact that with a mixture of this type, although it is not ready, it is very easy and fast to work.

Where to apply CPS?

Where a very durable wall surface is required, as well as in those facilities where there are no large budgets for repairs and specialist puttyers.

As for the appearance, design, any existing facade paint on the market fits perfectly on such plaster.

Next option.

Cement-lime mixtures

This type of plaster is also quite inexpensive, because it is the same DSP, but only with the addition of lime. Lime is used here to make the future facade layer as vapor-permeable as possible.

And when the walls “breathe” well, then, firstly, their service life increases, and, secondly, the microclimate inside the room becomes truly comfortable.

By and large, there are no disadvantages to such plaster.

The mixture can be made both by yourself and purchased ready-made. And the finished one, again, has more advantages. More - due to the fact that almost all manufacturers add various water-repellent components to this material, thanks to which the plaster sticks to the wall plane more easily and, after hardening, is not afraid of direct water ingress.

In general, the “verdict” on the lime mixture is very simple - you can safely use the material on standard objects where no special surface texture is required. It is easy to work with him, and such a facade will last for a long time.

Decorative polymer plasters

This is a more modern finishing material.

And these are not even plaster dry mixes for outdoor work, but a liquid mass ready for work.

It is made on the basis of several components:

• various acrylic dispersions;
• polyurethanes;
• epoxy resins.

As you can see, the composition is very different from the usual mineral plasters (such as DSP, for example).

It’s hard to say for better or worse, since there is a completely different instruction for using the material. Polymer mixtures of this type are more like putties than plasters. They should not be thrown on the wall, but.

There are also differences in terms of design. Such plaster can be both classically white and already painted. Or, for example, it may contain multi-colored pebbles of a small fraction in order to create an unusual effect on the future wall surface (these are the so-called mosaic putties).

As for the practical qualities, the polymer mixtures have proven themselves quite well. They serve for a long time, stay firmly on the plane.

Well, the disadvantage, perhaps, is their considerable price - not everyone can afford the material.

Silicone and silicate plasters

Silicate mixtures are often also called "silicon". This is also a liquid, viscous mass ready for use in buckets. It contains liquid potassium glass, which is the basis of the material. In order to make it easy to work with the material, various plasticizers are added to it - they increase the strength of the connection of the mixture with the wall and make it possible to apply the mass with a spatula.

In principle, silicate plasters are quite good, as they have a rich color range and adhere well to the surface.

However, there are some obvious downsides. This is a large consumption of material per square meter. meter and its high price. In addition, this mixture is caustic and therefore it is necessary to work with it with gloves and special goggles.

Advice: if you do not have experience in such a direction as wall putty, then it is better not to tackle the finishing of the plane with silicate plaster.
Because here it is very difficult to stretch the layer so that later there are no seams, growths, etc.
If the usual mixture can be wiped after drying, then the silicate mass must be done well IMMEDIATELY.

As for silicone plasters, in fact, these are the same silicate masses, only their base is not made of liquid glass, but of silicone resin. And so the properties are about the same.

And one more technology.

Heat-saving dry mixes - what is it

Recently, the issue of saving heat indoors is quite acute, because energy prices are constantly increasing. And in this regard, you can often hear that in the implementation of a project, heat-saving plasters were used.

It sounds good and new, but if you look, there is nothing “military” here. The whole secret is that either foam balls or perlite particles (these are small particles of light rock) are added to any mixture (in the same lime or ordinary DSP, for example).

Any building in an open area needs to protect the walls from bad weather and mechanical damage. Exterior plaster performs both of these tasks and becomes the basis for the decorative design of facades.

Exterior plaster at home - consider the pros and cons

Plaster for outdoor work is in demand at the final stage of construction brick buildings, concrete, cinder blocks or wood. The main advantages of this repair method are:

• Low price. Any other method of finishing wall cladding will cost several times more than the exterior plaster of a house.- from siding to tiling;
• With the help of plaster mixes, significant masonry defects, seams between bricks or cinder blocks, protruding ends of reinforcement, potholes, cracks, etc. can be repaired. An ideal surface for plaster is not needed, on the contrary, strong contact with the wall is ensured when the base is uneven;
• Repair of plastered surfaces is carried out simply and quickly, for it it is enough to dilute a little of the same plaster mixture and repair the damage that has occurred;
• Ample opportunities for the selection of the optimal composition for finishing work. External plastering of the house is carried out with various compositions, taking into account the type of walls, their size, the further "fate" of the plastered surfaces in terms of design (see below);

Exterior decoration of the house with plaster is not a universal repair method, it has characteristic disadvantages:

• You need to be able to plaster, no matter how trite this phrase sounds. Facade cladding with siding or wall insulation with roll insulators is much easier to do without the appropriate skills than plastering a wall with high quality. Initial experience can be gained on small surfaces - for example, when decorating window slopes with plaster;
• Preparation for finishing is quite laborious - it will be necessary to dilute significant volumes of plaster, lift them onto scaffolding and constantly move along the decorated facade. A significant part of the effort will not fall on the plaster itself, but on preparatory and auxiliary procedures;
• There will definitely be waste in the form of pieces that have fallen off the wall, splashed or accidentally spilled plaster mixture. And the less experience you have, the more waste when applying plaster will be;
• Good weather is needed for work, especially the absence of precipitation. You can cover yourself from rain or snow with impromptu canopies made of film or thick polyethylene; you will not be able to protect yourself from high humidity. It will lead to bad contact of the plaster with the wall and the likely delamination of the composition after a few days.

Durable and reliable plastering at home is ensured not only by the skill of the worker, but also by the properly diluted composition, high-quality tools and good weather on a working day.

The website site masters have prepared a special calculator for you. You can easily calculate the right amount of plaster.

Exterior plaster at home - varieties of smooth finishes

All available types of plaster compositions can be divided into three large groups:

• Decorative plasters. They are used at the final stage of finishing work, after which the walls acquire a finished appearance (colored, embossed, etc.). The application of such compositions is most difficult;
• Special plasters are mixtures with screening and/or heat-insulating qualities. They are used as additional protection against noise, moisture, frost and other things, including as a basis for decorative compositions;
• Ordinary plasters. Used to level the walls, which allows you to subsequently apply putty, paint or varnish on them. They also serve to protect block wall materials (brick, cinder blocks, aerated concrete) from direct exposure to atmospheric phenomena and other environmental influences.

Ordinary exterior plaster on brick or concrete is carried out with cement-sand mortars, not only outdoors, but also inside them. Other varieties of conventional plasters are gypsum or lime mixtures. They are used only for interior work, as they do not have moisture resistance. We will describe the method of external plastering using a sand-cement mortar, as detailed and clearly as possible.

How is the exterior of the house plastered?

Do-it-yourself plastering of external walls with cement and sand does not at all involve mixing these ingredients on your own. There are many ready-made dry mixes in hardware stores, which are brought to repair readiness according to the well-known advertisement "Just add water!" The other stages of our finishing path are as follows:

How is the exterior decoration of the house with plaster - a step-by-step diagram

Step 1: Preparing the base

Before plastering, the walls must be "relieved" of the old finish, whether it be whitewashing, putty or plaster of the previous generation. If the building is new, you should remove the influx of mortar and measure the walls for their convexity. If necessary, individual "humps" should be cut down with an ax, otherwise you will have to increase the layer of plaster or put up with the uneven application of it. Large cracks and potholes in the masonry, deep defects in concrete are filled with a cement-sand mortar "roughly", without leveling. It is enough to eliminate significant voids, the smoothness of the wall is provided later.

Step 2: Mixing the plaster

If you have to work with separately purchased bulk materials, then first they are mixed with each other in a dry form. The basic ratio of sand and cement is 4:1, but for greater weather resistance it is better to increase the "cement fraction" to 3:1. Cement is needed grades from M-300, M-250 and below will not provide long-term strength for exterior decoration.

If a ready-mixed dry mortar is used, the water content of the finished plaster must be accurately controlled. The concentration of the finished composition should be similar to thick (natural village) sour cream. This consistency sticks well to the walls and stays on them without any problems until leveling. The kneading is performed on a wide sheet of old linoleum, on sheet metal.

Step 3: Plastering

Before applying the cement-sand mortar, the wall should be moistened with water. The easiest way is to douse it from top to bottom with several buckets of water, spraying moisture on bricks or cinder blocks in a wide fan if possible. The best plaster will not adhere to a dry wall.. Take care of strong scaffolding or a convenient ladder in advance, and it is advisable to use scaffolding. They are provided with flooring, where you can put the tools and put a bucket of mortar, there are no such amenities on the stepladder.

The plaster is started from the upper and clearly visible corner of the wall, moving sideways and down in the so-called "square-nested" way. The size of the square drawn by the trowel is individual, for masters it is larger, for beginners it is smaller. You can start with a 40x40 cm square and gradually increase its sides. When throwing the plaster mix, the wall should completely hide under the bumpy layer, without gaps and gaps.

Step 4: Trowel Procedures

A piece of linoleum or a metal sheet is spread below and close to the wall (dense cellophane is also suitable). With the help of a long bevel, the excess mortar is cut off parallel to the wall and falls freely onto the prudently spread material. These "waste" can be used when mixing the next batch of solution.

If the wall next to the fresh plaster is dry, it is moistened with a spray bottle. Then they throw in a creamy mixture, again wait for it to dry for some time and cut off the excess with a long bevel. When the entire wall strip - from top to bottom - is ready, it is rubbed with wooden or plastic trowels. The movements of the trowels should be uniform and measured. Upon completion of the grouting procedure, they proceed to plastering the next section of the facade or wall.

When building external walls, as well as leveling or cladding facades, mortars are used that are characterized by certain properties. Dry mortars for outdoor work and water resistance contain special additives that increase the effectiveness of protecting various surfaces from precipitation and temperature changes, as well as from the destruction of the structure of materials under the influence of ultraviolet radiation or for other reasons.

Features of building mixtures

The main advantage of dry compositions relative to self-kneading solutions is the stable ratio of components and their relative purity. This is a guarantee of support for a given brand of the finished mixture. Additives, in turn, purposefully improve the technical characteristics of the masonry or facing mortar and reduce the consumption of the binder. Compositions for plastering, for example, should have increased adhesion and have plasticity, and mixtures for pouring floors should spread without leaving sagging.

An important factor is the possibility of batch preparation of the composition for the required amount of work. Material losses, in this case, are minimized due to the fact that there is practically no unused solution. Bags with dry mixes are neatly stored. Bulk material is easily mixed using a mixing attachment inserted into a conventional drill. At the same time, it does not need any preliminary sifting.

Requirements for mixtures for outdoor use

External surfaces are treated with moisture-, frost- and heat-resistant compounds. The hardened solution must have:

• certain plasticity;
• permissible vapor permeability;
• impact resistance;
• strong adhesion to the base.

Heating as a result of the direct action of sunlight should not lead to softening of the frozen layer or destruction of its structure, and under the influence of ultraviolet - to color fading.

Lime and gypsum compositions are not recommended for outdoor use.

Types of building mixtures for exterior decoration

The mixtures used for plastering facades are conventionally divided into several groups:

• mineral;
• polymeric - anhydrous or water-based;
• silicate;
• silicone.

The mineral compositions include traditional cement-sand mixtures. Additives are introduced into them that increase the resistance of the applied layer to moisture, temperature changes, and also improve the frost resistance of the coating. Mineral plaster has a high vapor permeability, allowing the walls to "breathe", and the owners to forget about the appearance of condensate. The advantages of cement mixtures include their low cost, good coloring and fire safety. But, at the same time, mineral plaster does not adhere well to perfectly flat surfaces, has low elasticity and insufficient hydrophobicity.

Polymer mixtures diluted with water are distinguished by good adhesion and optimal moisture resistance. The treated surfaces are not afraid of ultraviolet radiation and are not prone to cracking, but acrylic and polyvinyl acetate compounds do not tolerate elevated temperatures well. The disadvantages of aqueous polymer mixtures include their rapid drying during the application process, as a result of which, if the work is performed in the wrong order, stains may appear at the joints of the plastered areas. Another disadvantage of such compositions is their "attractive power" in relation to dust and dirt, which accumulate on surfaces quickly enough. But this disadvantage is compensated by low absorption - a soiled wall can be easily washed with plain water.

Acrylic plasters are produced ready for use.

Polymer compositions with epoxy and polyurethane binders form a durable layer that can withstand mechanical and atmospheric influences. Mixtures have:

• excellent adhesion to different materials;
• hydrophobicity;
• the possibility of creating facades in different colors;
• incombustibility;
• versatility.

With all the undeniable advantages, anhydrous-based polymer mixtures have a serious drawback. With a significant increase in temperature (more than 140 degrees), the layer of plaster begins to release toxic substances. This factor determines the scope of polyurethane and epoxy compositions.

In silicate mixtures for finishing work, there is liquid potassium glass. They are produced in a ready-to-use form, and their properties meet most of the requirements for building mixtures for outdoor use. The disadvantage of the finished coating is low vapor permeability and low elasticity, which contributes to the appearance of microcracks on the surface. Most often, silicate mixtures are used for walls made of cellular concrete and shell rock.

Silicone compounds are among the most expensive mixtures for outdoor use. Silicone gives the layer elasticity, and therefore, during operation, cracks and chips do not appear on the coating. Surfaces are able to self-clean in the rain, so the facades do not need to be washed. Plastered walls "breathe" due to the good vapor permeability of the layer, and do not get wet, as they have excellent moisture resistance. Mixtures can be applied to substrates of different quality and materials. For better adhesion, surfaces are pre-treated with appropriate primers.

By appointment, plaster mixtures for outdoor work are:

• leveling;
• decorative;
• warming.

Leveling compounds are used, as a rule, as a basis for further facade finishing. With their help, seams and cracks are closed, shells and various kinds of bulges are smoothed out. At the same time, the leveling layer performs a protective function, protecting the surface from moisture and other negative phenomena.

Decorative plaster is intended to improve the appearance of the facade. A wide selection of textures allows you to implement various design ideas. The most original representatives of decorative mixtures for outdoor use are considered to be compositions such as "bark beetle" and "pebble" plaster. When applied, a structured surface is formed due to the presence of granular components.

As part of the "warm" plaster contains fillers with low thermal conductivity. These include:

• paper;
• cellulose;
• cork crumb;
• polystyrene granules, etc.

The heat-insulating mixture is applied in a thick layer. For greater reliability, in this case, a reinforcing mesh is applied to the wall.

Choice

When buying building mixtures, certain nuances should be taken into account, namely:

• climatic features of a particular region;
• the presence of complex structural elements - perhaps more plastic compositions will be required;
• the need for additional wall insulation;
• compliance with the requirements established by the manufacturer - temperature, humidity, etc.

When applying thick layers of plaster, care should be taken to purchase a reinforcing mesh. Building mixtures should be bought with a small margin, since in the process of work they may be overused for obvious reasons.

All plaster mixtures for outdoor use must meet two main criteria: high strength and durability. In most cases, the plastered facades of buildings are subsequently covered with various finishing materials. But there are also options for using plaster as a topcoat. In such cases, they can be made according to special recipes that allow obtaining the original appearance of facade walls without additional finishing.

Currently, manufacturers of building materials offer developers a huge range of dry plaster mixtures, it is possible to choose the best option. Due to innovative additives, mixtures have excellent performance, can be used on all types of buildings, etc. But all of them have two drawbacks.

Depending on the condition of the walls, the thickness of the plaster layer can exceed 3 cm, which significantly increases the need for materials. This is another reason not to use purchased materials.

Professionals consider it appropriate to use store mixes only in a few cases:

The composition of plaster mixtures for external works is selected taking into account their specific place of use. We will talk about the most commonly used cement-based materials. But there are cases when the restoration of buildings of an old building is carried out, in ancient times original mixtures were used, which are almost never used today. They do not have high performance by modern standards, but knowledge of the recipe can come in handy. In this regard, we will try to give the maximum list of materials.

Regardless of the composition, there are several general recommendations for all mixtures.

1. Use only river sand. If there is clay in it, then the amount of cement should be increased.

   

2. The prepared cement mixture should not delaminate for at least half an hour. If water appeared on top of the bucket earlier than the specified period, then this means that there is not enough cement in the solution. Add it and mix the whole mass again.

   

3. If the solution is very liquid, then sand must be added to increase the density, and not cement. It is desirable that the sand is dry. Cement absorbs liquids very little, to increase the density it will have to be added a lot.

   

4. Among builders there is the concept of "fatty" solution. To obtain it, you need to increase the amount of cement by at least 30%. "Fatty" solutions are distinguished by increased mechanical strength, quickly harden, are not afraid of prolonged direct exposure to water, perfectly connect to surfaces. The disadvantage is an increase in cost and a high probability of cracking during solidification.

   

5. Use the mixer for mixing only to prepare a small amount of the solution. Professional builders do not use such a tool, its performance is too low. To prepare a solution for one wall, you will have to work with a mixer for several days. This "technology" is used only by amateurs.

   

How to prepare a decorative cement plaster mixture by hand

If you want to prepare multi-colored plaster with the addition of mineral dyes, then you definitely need to buy white cement. True, if a bag of 50 kg of an ordinary one costs around 200 rubles, then the price of white is about 500 rubles for the same bag.

Practical advice. There is a way to further reduce the cost of a recipe for making colored plaster. Do not add dyes, but select the color by using different sand. Depending on the location of the quarry, it can be from white to yellow or grayish. Accordingly, the plaster will be the same color. By the way, sand never burns out; in terms of color stability, no even the most expensive mineral dyes can be compared with it. Of course, you need white cement.

For example, we will consider the option of manual preparation of bark beetle plaster. For finishing facade walls, this is one of the most acceptable and beautiful options.

The texture of the plaster "bark beetle"

Step 1. Prepare a place and tools for kneading. You can knead on a ready-made even concrete base, if it is not there, then use pieces of sheet iron. For work you will need a shovel and a container for water.

Step 2 Prepare materials. Due to the fact that we make bark beetle plaster, there is no need to sift the sand. The solution is prepared in the following proportions: cement - one part, sand - three parts, stone chips - one part.

If you need a lot of mortar for work, then store the materials in the immediate vicinity of the mixing site.

Step 3 Throw sand on a pile, add stone chips and cement on top. No one measures material with buckets, consider shovels. For kneading, you need to have shovels.

Practical advice. Properly organize the workplace, it will greatly speed up and facilitate the kneading process. It is better to throw a bag of cement on a large pile of sand, cut the package in half with a shovel and take it directly from the halves of the bag. Do not worry that he will wake up a little, then pick him up along with the sand.

Keep in mind that from one bag of cement weighing 50 kg, approximately 0.25 m3 of mortar is obtained. One bag has approximately 15 medium shovels. This knowledge will make it easier for you to calculate during the mixing of the solution. This means that about 45 shovels of sand and 10-15 shovels of stone chips should be taken per bag of cement. It is quite difficult to prepare such a large batch by hand, practitioners recommend using half a bag of cement at a time. The amount of sand and crumbs is proportionally reduced.

Water is a little more difficult, its volume largely depends on the moisture content of the sand. If you have it in an open area and got caught in the rain, then the amount of water may decrease by a third. It is impossible to give exact recommendations, determine the need as the batch is prepared. To begin with, pour about 4 buckets into half a bag of cement, then you will orient yourself as you work.

Step 4 Throw a bunch of material first in one place, and then back to the center of the site. If its dimensions do not allow you to transfer the entire amount at once, then break it into two parts. During the transfer, the components are not mixed very thoroughly, but this is not a problem. In the future, the ingredients are placed evenly throughout the volume.

Step 5 Make a hole in the middle of the pile, it should be quite large. Make sure that there is always a shaft of dry mortar around, it does not allow water to flow out during kneading.

Step 6 Pour water into the hole and start kneading.

To do this, gradually mix the dry mixture with water in small portions and overturn with a shovel. Move in a circle, the dimensions of the protective shaft should always be approximately the same around the entire perimeter of the hole. Sand with cement can be taken both from the middle of the hole and from the edges. The main thing is not to make a hole through which water will leave. If the solution is thick, then add a little water.

Step 7 When the dry mix is ​​low, increase the mixing speed. Cover areas with very thin mortar with dry sand and mix immediately.

It is not necessary to achieve one hundred percent uniformity, additional mixing will occur during the set of mortar in the container before plastering and during the plastering of surfaces.

Practical advice. In order to find out exactly how much stone chips are needed, it is recommended to make a small test batch. Then plaster a small section of the wall with the mortar and make a pattern. If there are few “bark beetle moves”, add crumbs.

How to make a "warm" solution

This material is very popular in recent years due to the desire of homeowners to reduce heat loss. To reduce the thermal conductivity, not ordinary sand should be added to the solution, but perlite filler.

For one part of cement, you can give 5 parts of filler, if you need to make the mass stronger, then increase the amount of cement. Water, as always, is added as needed.

Important. When working with dry perlite, protective masks must be used. Many builders ignore this requirement, but in vain.

Step 1. Measure out the right amount of perlite. This is a fairly expensive material, do not overspend. It is recommended that you first find out the entire volume needed for one batch and prepare one large container for it. In the future, make a small hole in a plastic bag and carefully fill it. Avoid heavy dusting, keep the bag as low as possible above the container.

Step 2 Turn on the concrete mixer and pour water.

It is advisable to pre-measure its quantity. The fact is that this filler absorbs much more water than sand. If you need to prepare a large amount of the solution, then all the proportions of the ingredients for one batch must be remembered and not experimented every time.

Step 3 Add a special soapy resin to the water, if it is not available, then liquid soap is also suitable at the rate of approximately 100-150 ml per concrete mixer with a volume of 0.25 m3. Dilute the soap a little with water, you need to lather it. You need about 2.5 buckets of water. Do not pour more, otherwise the perlite will rise up and not get wet.

Practical advice. Never pour completely dry perlite into a concrete mixer, soak it in a container first. To do this, pour water into it, add perlite and mix with a shovel until a mushy state is obtained. The mass is considered ready after the perlite stops dusting during stirring.

Step 4 Throw wet perlite into a concrete mixer¸ if it sticks to the walls, then add water.

Only a little, otherwise problems will arise later - by adding perlite, the excess cannot be removed. The fact is that dry perlite will float on top and will not be able to absorb moisture. You will have to mix it again by hand and only then add it to the mixer.

Step 5 After the perlite has become homogeneous, start adding cement. Pour it in small portions, do not allow the formation of balls. It is very difficult to get rid of them later. If the mortar is planned to be used for plastering some wall surfaces, then increase the amount of cement. Constantly monitor the consistency, add water as needed.

Practice shows that, despite all efforts, it is not possible to completely avoid sticking of perlite with cement to the walls of a concrete mixer. It is necessary to stop the concrete mixer, gently clean the walls of adhering material with a trowel and mix it a little with the ready-made material inside the barrel.

Step 6 At the last stage of preparing the mixture, add sand. As the concrete mixer fills, increase its angle of inclination. Keep in mind that the greater the angle of inclination, the worse the mixing process.

If the mixture sticks to the walls again, then you need to periodically stop the mixer and clean its walls. There are situations when the mass in the middle of the volume of the mixer is normal, but liquid on the sides. Stop the mechanism, select two or three buckets of mass from the middle, tilt the agitator and turn it on again. In this position, the mass is better mixed. Everything is fine - add the removed mass again, tilt the agitator and turn on the engine.

It is more difficult to prepare such a solution than ordinary cement-sand, this must be understood and not be afraid of the first difficulties. Some professionals advise adding slaked lime to the solution, we consider this an optional condition. The fact is that perlite itself inhibits the development of microflora and no additional ingredients are required. But the final decision is yours. There is a desire and opportunities - add lime.

Where is it better to do the mass, in a concrete mixer or a mortar mixer?

First you need to tell how the mortar mixer differs from the concrete mixer.

The main element is a rotating drum, to the walls of which the blades are welded.

Advantages- versatility. Concrete and sand solutions can be prepared in a concrete mixer.

Flaw- the quality of mixing does not always meet the required parameters. To improve, you have to significantly lengthen the process. Another disadvantage of a concrete mixer. During the preparation of the solution, as the container is filled, it must be constantly raised (reduce the angle of inclination), and the principle of operation of the unit is such that the greater the angle of inclination, the better the solution is mixed. Accordingly, if a lot of mortar needs to be prepared in one batch, then the concrete mixer must be periodically partially released, the angle increased and the remaining mortar mixed. This takes time and energy. Mortar mixers do not have such a disadvantage.

Mortar mixer

The body is circular in shape and stands motionless. Blades rotate inside the body. The advantage is excellent mixing quality, cement and sand lumps are completely broken. The disadvantage is that concrete cannot be prepared in a mortar mixer. The fact is that large fractions of crushed stone fall into the gap between the rotating blades and the fixed bottom. The mechanism jams, which causes the electric motor to burn out.

Water is first poured into all mechanisms, and only then dry materials are added.

Cement should only be poured into water or a very liquid solution. If this is not done, then balls will roll in the concrete mixer, it is almost impossible to completely break them. This does not apply to the mortar mixer, it does not create such problems.

After completion of work, be sure to thoroughly wash the units. It is strictly forbidden to beat off the hardened solution with a sledgehammer or crowbar. During such procedures, irregularities appear on the body, and then an increased amount of mass will accumulate in them. Negative processes are developing on the rise.

Video - How to quickly wash a concrete mixer

When connecting the equipment, unconditionally comply with the requirements of the EMP, you work in constant contact with water, which greatly increases the risk of electric shock.

Never attempt to clean the surfaces of the agitators while they are rotating as this can cause very serious injury.

We told only two recipes for preparing mixtures for outdoor work. If you master them, then any changes in the recipe and technology will not be any difficulties.

Video - Manual preparation of plaster mortar