Anyone who has worked on wall finishing knows that when applying a thick layer of plaster, the material may not be able to withstand its own weight and begin to peel off from the wall surface. To prevent this from happening, a reinforcing mesh is used. It is mounted on the wall and takes on part of the load.

In what cases is a mesh needed?

If the walls are plastered without a mesh, there is a possibility of the material peeling off under the influence of its own weight. Thanks to the reinforcing mesh, a monolithic slab is created that can withstand any load. For plaster of different thicknesses, different meshes are created, designed for a specific load.

The use of a mesh makes it possible to form a durable layer of mortar, on which cracks will not appear even with prolonged use of the room. This result cannot be achieved without the use of the described products.

It is worth noting that even with improper mixing or non-compliance with the temperature level, the mesh helps maintain the integrity of the plaster. There are special meshes for facades that are not subject to corrosion.

Types of grids

On the building materials market you can find many types of meshes onto which plaster is applied. In order not to make a mistake when choosing, it is worth considering the main types of such products and their features:

To choose from the proposed options, it is enough to determine in what conditions the mesh will be used. If you need to plaster the facade, it is better to buy metal or fiberglass products with large cells. When applying compounds to interior walls, you can use a plastic mesh.

How to attach the plaster mesh

To understand how to properly attach the mesh to the wall, it is worth considering the two most popular types of mesh - fiberglass and metal. It is much easier to secure the first named type of product, since for this you only need to screw in several screws at an equal distance from each other. Such fastenings are sufficient to securely hold the mesh.

To keep the mesh more securely, you should roll it out across its entire width in one piece, without dividing the product into several. Vertical beacons are installed at a distance of about two meters from each other during installation. After the mesh is hung on the screws, the plaster applied seals it to the wall, so additional fastening elements are not needed.

The installation process for metal mesh is slightly different. This is due to the fact that under its own weight such a product is not able to be securely held on the mounts. Also, the cells of metal mesh are large and require additional fastening with mounting tape.

To secure it, you only need to cut off part of the mounting tape so that it can completely cover one cell. After cutting the mounting tape, it is fixed to the wall with self-tapping screws. You need to calculate the distance between the fasteners in such a way that the mesh does not sag on any section of the wall.

Surface preparation

Before you start plastering the walls, you need to clean the surface of dirt and old finishing materials. After finishing work, there should not be any additional materials on the surface, as they can cause the plaster to peel off.

After cleaning the surface of the walls, it is necessary to apply a primer. Such compositions increase the strength of the wall and improve the quality of adhesion. They also prevent mold and corrosion. The primer helps the surface dry quickly and promotes better absorption of compounds that are applied after it.

Applying plaster

After preparing the surface and fixing the reinforcing mesh to it, plaster is applied in several layers. To properly apply the composition to the surface, you should consider the features of creating different layers:

First layer. Plaster is usually applied in two or three layers, depending on the material of the walls. Concrete, for example, requires three coats. The first of them is called “spray”. The plaster at this stage has a creamy consistency and is thrown onto the wall surface in any order. The composition can be spread, but throwing it on allows you to speed up the process. After applying plaster to a certain area of ​​the wall, you need to wash the tool. After casting, the composition is leveled with a two-handed spatula from bottom to top.

Second layer. After the first layer has completely dried, you need to knead the plaster, the consistency of which should resemble dough. Then you need to throw the composition on the wall and, taking a trowel, spread it in the horizontal and vertical directions. It is after applying the second layer that the reinforcing mesh is completely covered with plaster. If it still protrudes to the surface, you need to apply the plaster again.

Third layer. At this stage, you need to level the composition more carefully so that there are no errors left on the surface of the walls. Before applying the finishing layer, you need to wet the surface of the plaster.

This mesh plastering technology is universal and can be used when working with walls made of various materials.

The final stage of work

After the plaster has completely dried, it must be prepared for fixing finishing materials. To paint and wallpaper, just sand the surface with sandpaper. If there are noticeable unevenness on the wall, you need to start using the largest brand of paper. For ease of work, a piece of product is clamped on a grater. Grinding is done in a circular motion with little effort so as not to create new defects on the surface.

When the wall becomes uniform, you need to change the brand and continue grouting. If the surface will be painted, you need to take P120 paper. During the entire process, you should use goggles and a respirator to protect yourself from dust.

Since it is quite difficult to sand the surface in the corners, it is worth working either without a grater or using bars with sharp corners. If you want to make the work process easier and faster, you can purchase an electric grater. But to treat the walls of one apartment, it is not profitable to buy such a product. After sanding, you need to sweep away the dust with a brush.

Applying plaster under wallpaper and painting

Before starting work, you should determine exactly how the room will look and what will be used as finishing materials. If you choose wallpaper, you need to determine its type and thickness in advance. If they are thin, you need to apply several layers of leveling plaster. This will allow you to hang the wallpaper without any unevenness or bubbles.

For the room in which wallpaper will be hung, it is better to purchase ready-made dry mixtures, since using them you can prepare higher-quality plaster.

If plastering the wall surface occurs before painting, you should carefully prepare the wall, without leaving even small irregularities on it. The whole process is carried out in several stages:

• first, a leveling layer is thinly applied;
• then, if necessary, two more layers are applied to eliminate defects;

The mesh is a rolled building material used to reinforce internal and external surfaces for various purposes. The maximum effect is observed in new houses that have not yet gone through the shrinkage stage, but in a number of works it cannot be done without it. The cell sizes, diameter and base are different; in each individual case it is important to choose the right option.

The material is used to strengthen the working coating, protect the applied mixture from delamination and cracking, and prevent deformation of the finish. Its installation significantly reduces the influence of mechanical, humidity and temperature influences and increases the quality of adhesion of solutions to substrates. Plastering walls on a grid (and other surfaces) is considered mandatory when:

• External facade cladding.
• Reinforcement of floor screeds.
• Finishing smooth tile building materials with low adhesion, such as polystyrene foam.
• Strengthening areas with a high risk of plaster shedding: openings, slopes, joints.
• Thick-layer application of the solution (over 2 cm).
• High risk of building shrinkage.

Types of meshes, features and applications

The base material must be strong, alkali-resistant, as light and durable as possible; steel, plastic and fiberglass have suitable characteristics. Metal products, depending on the manufacturing method and type of fabric, are divided into thin and flexible woven (with a small wire diameter), braided, welded (the most rigid, recommended for high mobility of the base) and expanded metal, obtained by cutting holes in a stretched sheet.

Depending on the rolled products used, they are all divided into types of stainless steel and galvanized and non-galvanized wire. When using them as a mesh under plaster, it is worth choosing a protected type, with a zinc coating; it better withstands the alkaline effects of cement and is less susceptible to corrosion.

Fiberglass fabric is obtained from threads of molten glass; it is impregnated with special compounds to increase strength, flexibility and resistance to moisture, alkaline and biological influences. It is the thinnest, it is recommended to choose it when finishing, applying a rough or finishing layer within 2-3 cm, arranging warm and self-leveling floors. Characteristic properties also include high thermal stability (up to 1500 °C); this plaster mesh tolerates temperature changes well. The intended purpose of fiberglass is determined by the size of the cells (for interior work it is recommended to buy a 2x2 m fabric, for facades and exteriors - 5x5).

The polypropylene-based variety is universal; its advantages are: lightness, compactness, strength and affordable cost. The specific option depends on the size of the cells: small (up to 6 × 6) is used for reinforcing thin-layer plaster (up to 20 mm), medium (13 × 15) is recommended to buy when reinforcing coatings up to 5 cm thick, including loaded ones, large (22 × 35) – when working with large surfaces and uneven facades. This group includes many subtypes and brands: Plurima (based on polypropylene with high chemical inertness), Syntoflex (ultra-strong and geometrically stable brand), STREN (recommended for use under the influence of aggressive environments), Armaflex (reinforcing any type of masonry, including uneven ones). The cost per square meter depends on the quality, chemical inertness and strength of the plastic and varies from 11 to 110 rubles.

Which mesh should I use and in what cases?

The main determining criterion is the thickness of the applied solution; when working indoors, a reliable foundation and thin-layer leveling (up to 20 mm) can be abandoned. When cladding facades, reinforcement is always carried out: metal mesh reinforcement for plaster is selected when the wall level deviates by more than 30 mm, and if there is a significant risk of destruction of the base or shrinkage of the building, it must be welded. In other cases, to cover standard masonry, fiberglass or plastic with a density in the range of 160-300 g/m2 is sufficient. Smooth foam boards that insulate the facade are recommended to be finished with light fiberglass.

It is better not to skimp on external surfaces; these areas require varieties coated with zinc or impregnated with alkali-resistant compounds. To eliminate doubts, the material is checked by immersing it in a soapy solution for several days; high-quality products do not spread or change color. When purchasing façade mesh, attention is paid to the breaking load value. On flat areas, a blade with 1800 N and above is used, on curved areas - in the range of 1300-1500.

When finishing interior spaces, the same rules apply - thick-layer coating requires reinforcement with metal, thin-layer coating with fiberglass or polypropylene. The latter type is also used as masonry: an elastic fabric with 5x5 cells is placed between bricks or blocks and increases the adhesion of rows and products. The recommended density range for synthetic mesh for internal plaster is 110-160 g/m2, this is enough to ensure crack resistance and keep the layer within 2-3 cm. For sealing joints of building boards (plasterboard, fiberboard or chipboard), strengthening window openings and areas Serpyanka is a good choice for connecting to the ceiling and reinforcing mastic roofs - thin fiberglass with a cell size of 2x2 mm and a density in the range of 45-60 g/m2.

The nuances of installing a mesh with your own hands

The metal variety weighs the most and requires secure fixation with screws or nails. It is degreased (galvanized steel is simply washed with water or wiped with a rag) and cut with special scissors into pieces of the required size, taking into account the obligatory overlap of 10 cm into adjacent areas. In some cases, holes for dowels are prepared in advance, the step is 25-30 cm, on average by 1 m2 requires 16 fasteners. If possible, the edges are fixed with mounting tape (when working with large-mesh options, its use is mandatory).

It is better to finish metal-reinforced surfaces in two layers (not counting the spray), the second, thinner and leveling one is applied after the first has dried slightly. This type must be reliably covered with the mixture; it is important to choose the correct cross-section and method of connecting the wire; the thickness of the coating cannot be reduced below the recommended value.

When working with fiberglass and polypropylene meshes for plaster, the mortar itself or self-tapping screws can act as fastening materials. In the first case, the canvas is placed in the middle of two layers; to increase density, it is better to unwind it directly on the spot, rather than cut it into separate pieces (the exception is the finishing of foam plastic, where segments are better suited). Plaster in the direction from the middle to the edges.

During the process, it is important to prevent the formation of air bubbles and avoid stretching of the plastic mesh.

But the more reliable and correct option is to fasten the dowels to a still dry wall, followed by spraying and applying the first layer as a base. The number of fasteners is minimal (one per canvas with a uniform step of 1-2 m), with a significant level difference they are used for installing beacons. The first layer of mortar is placed along the width of the product; after laying it, they proceed to the adjacent one, tracking the overlap of 10-15 cm with each other. Plastering for the purpose of leveling should also be done from the middle to the edge. Avoid sudden movements with a spatula, especially when working with facade mesh, otherwise they will come off along with the finishing composition. Correctness is checked visually - if they are visible under the leveling layer, then it is better to increase it by 1-2 mm.

Material cost

Carrying out work on plastering surfaces is an important and responsible task. It is imperative to follow the correct technologies that will allow you to securely fasten the material to the wall without unnecessary difficulties so that it does not peel off under any circumstances.

Reinforced mesh for plaster is best suited for solving this issue, since it can be used to create a special layer that, on the one hand, will improve adhesion to the wall, and on the other, will allow the material to be securely fastened together. This approach is used when performing a large number of construction works, and it has proven itself only from the best side. So they use it everywhere and are always satisfied with the result.

What is a mesh for plastering walls?

The reinforcing mesh for plastering walls fully corresponds to its name and is a special product that has small cells that make it possible to effectively contain the solution so that it does not fly apart in different directions and sticks to the wall as firmly as possible.

The following varieties are distinguished:

• . masonry mesh, which has cells measuring 5x5 millimeters and is used with brick walls. Made mainly from polymers;
• . universal mesh, which can have different cell sizes and is used in all types of work where it is necessary to cover a large area at a time;
• . fiberglass mesh, which has a cell size of 5x5 millimeters and is highly resistant to any type of chemical attack, and also easily tolerates high loads that can be detrimental to other materials;
• . Plurim mesh, made of polypropylene and having a lightweight weight, which makes it easy to use without greatly increasing the load on the walls;
• . armaflex - polypropylene material with reinforced nodes. It is used in those types of work where an increased level of load is expected;
• . syntoflex - has “immunity” to chemical and mechanical effects;
• . steel mesh - is one of the most durable models, but is not suitable for outdoor use due to low resistance to precipitation;
• . galvanized mesh - is a modification of the previous model. With the help of special treatment, it has received protection against corrosion, so it is applicable for any purpose, including operation in conditions of high humidity.

The range of products is quite large, so you need to know how to choose the right material when purchasing. The sales consultant will try to sell the product that is beneficial to him, so it is better if the client himself understands the varieties.

How to choose a mesh for plastering work?

Inexperienced users often have the question of what mesh to reinforce the plaster with? Here everything will depend on the current working conditions, since there are not only universal models, but also narrow-profile products suitable for only one purpose. Therefore, you need to first consult with the experts or search for the necessary information yourself. The correct choice is very important for further operation, so you need to take it with the utmost seriousness.

Fiberglass reinforcing mesh for plaster is one of the best universal models, as it combines almost all the positive qualities that such a material should have. It is not afraid of corrosion, since it does not contain metal elements, is not sensitive to moisture and temperature changes, and withstands mechanical loads well. Therefore, many professionals advise purchasing this particular model.

In any case, the reinforcing mesh for plastering walls should not be inferior in performance to the base material. This is especially true for strength, reliability and durability. The base simply must last no less time than the finishing material, otherwise all sense in its use is lost.

How to work with reinforcing mesh?

The reinforced mesh for plaster must be securely and tightly attached to the wall so that it does not disturb the correct balance that will be established upon completion of the finish. Its installation is carried out in stages according to the following scheme:

• . First, the working surface is divided into separate zones, in each of which a certain number of beacons are marked. They can be calculated using a standard formula, the main indicator of which is the square footage of the wall being processed.
• . Next, using a drill, holes are drilled and reinforcement mesh fastenings for the plaster are inserted. They are quite standard screws, but with large diameter heads that will securely hold the mesh and press it against the wall.
• . Next, apply a base layer of plaster, without using a mesh.
• . After this, the mesh is put on the fastenings and tightened as much as possible. But you should not overdo it so that the material does not burst from excessive stress.
• . Finishing work at the final level can be carried out on top of the installed mesh. In this case, the plaster will lie smoothly and adhere without any problems. The main thing is to smooth the top layer well so that it looks beautiful.

The price of reinforcing mesh for plaster will depend on the type chosen. The larger the cell size, the correspondingly more expensive the cost of the material.

Today we’ll talk about why and when plaster reinforcement is needed. In recent decades, we have adopted a conditional renovation of premises, the so-called “European-quality renovation”. It allows you to more thoroughly finish surfaces, using both European standards and modern materials, and limiting yourself only to materials, without particularly paying attention to repair standards.

European standards recommend, but do not require, the use of reinforcing mesh in difficult cases. These reasons have been misinterpreted and have become legends. It is believed that it is necessary to reinforce plaster to improve its adhesion to the wall and prevent the formation of cracks. This is not entirely true. To improve the adhesion of the plaster, it is necessary to thoroughly clean the wall and use appropriate primers. The reinforcing mesh reduces the visibility of cracks, rather than preventing their formation. Let's look at this question in more detail.

Reinforcing mesh can be metal or plastic. Fiberglass mesh is also popular as an analogue of plastic. Metal is used when plastering with strong unevenness and protrusions, sometimes exceeding 4-5 cm. When leveling, a thickened layer of plaster is created, which, after complete drying, can swell and come off. This is especially true when plastering with clay without using filler. To prevent this from happening, reinforcement with a large-mesh (more than 4 mm) metal mesh is needed. This is actually a plaster mesh. Why not plastic? Because plastic is less durable, corroded by aggressive cement-sand plaster and is usually used under gypsum plaster of small thickness. That is, this is a painting mesh with a mesh size of 2-3 mm, which is reasonable to use for finishing the wall with putty or plastering with gypsum mixtures on relatively smooth walls, with a plaster application thickness of less than 20 mm.

In accordance with both our SNiP and European building standards, the thickness of the plaster layer made with a gypsum mixture is on average 15 mm. This plaster is actually applied in one layer. When reinforcing, the mesh is recessed into a freshly applied layer of plaster to a depth of at least 2/3 of the entire layer without the formation of folds, with an overlap of at least 100 mm (in places where one structural element adjoins another - at least 200 mm).

In most cases, reinforcement of plaster on the surface of walls is not carried out continuously, but only at the junctions of various finishing surfaces and structural elements. But when applying a layer of plaster to the surface or when working in a newly erected building that has not yet shrinked, it is recommended to carry out reinforcement over the entire area.

Research conducted by European manufacturers has established that when gypsum plaster is used in new buildings subject to structural deformations, it is possible to reduce the risk of cracks on the surface of the putty plaster, provided that the plaster is applied in the form of a layer 20 mm thick and reinforced with a plaster mesh. My practical experience confirms these studies. So, when finishing an apartment of 100 square meters. meters on the seventh floor of a nine-story brick new building, immediately after the building was commissioned, continuous reinforcement of the walls and ceilings with plastic painting mesh was carried out. When working with gypsum plaster, some walls and ceilings were even reinforced in two layers. Plastering and gypsum mixtures were carried out on the cement-sand plaster left behind by the builders. The walls were being prepared for painting. Within three years after the completion of the renovation, cracks, barely visible to the eye, appeared in the putty layer on the ceilings of all large rooms and on some walls. Such cracks can be easily repaired during the next cosmetic repair, for example, when repainting walls or wallpapering. It is not difficult to guess that saving on reinforcing mesh during finishing work in a damp, freshly built building would lead to the formation of cracks throughout the entire thickness of the plaster layer and would force at least the redoing of the putty layer throughout the entire room.

Plaster mesh. Why is plaster reinforcement needed?

Leveling walls with plaster mixtures requires preliminary preparation related to surface treatment and installation of beacons. Often, plaster mesh is used for finishing - metal, plastic or fiberglass. In what cases is plaster reinforcement necessary, and what mesh is suitable for this?

According to European standards, plaster mesh is recommended for use as a reinforcing material. There is an opinion that it is necessary to reinforce the plaster for better adhesion of the mortar to the wall surface, or that the use of meshes 100% guarantees the absence of cracks. In fact, the solution sticks well to the surface if the surface is cleaned and primed. And the use of plaster mesh allows you to reduce the number and size of cracks, making them invisible.

Among the building materials available on the Ukrainian market, plastic, fiberglass and metal plaster mesh are available. The mesh creates the frame of a layer of starting or finishing plaster applied to the wall. It must meet certain requirements. It should be 150-170 g/mkv.

Ordinary plastic (painting) mesh is only suitable for gypsum plasters that do not contain cement. The fact is that it is susceptible to corrosion by alkaline media. Therefore, it is used for finishing plaster. In other cases, for a small layer of plaster (up to 20 mm), fiberglass meshes and meshes impregnated with special compounds can be used.

Metal mesh for reinforcing plaster is used in cases where the surface of the wall is so uneven that the differences are 4 centimeters or more. When dry, the thickened layer of plaster behaves unpredictably and can swell and come off. In this case, even preliminary priming of the walls does not help. If the plaster mixture contains cement, then it is worth using steel mesh, because compared to other materials, metal is most resistant to corrosion by alkaline media.

Metal reinforcement is also recommended when plastering with clay. For clay, it is better to use a mesh with a large cell - 50x50 mm. When externally plastering the walls of the first floor, metal mesh is also used, because this part of the wall is often subject to mechanical stress.

How to attach a plaster mesh to a wall? To do this, you need dowel-nails with an outer diameter of 6 mm and a self-tapping screw of 4.5 mm. We drill holes for fasteners and cut a piece of mesh to fit the height of the wall. Next, we fix the mesh from bottom to top with dowel nails, simultaneously straightening and tensioning it. You can use washers for fixation, but this is expensive. It is much more profitable to use galvanized perforated tape, which is easy to cut. When attaching the mesh to the wall, you need to ensure that it does not lag behind the wall by more than 1 cm and does not sag. At the joining points you need to overlap.

The company "Metiz-service" produces and sells steel plaster mesh of all types: expanded metal (CPVS), welded, as well as chain-link mesh with small and large mesh. Knitting wire and galvanized punched paper tape are also available for sale.

Reinforcement of plaster (external and internal finishing)

When reinforcing coatings, the mesh is attached in any convenient way directly to the surface of the wall covering. The base can be a wall made of concrete blocks, brickwork, or a wooden surface. The cell size and mesh rigidity depend on the thickness of the plaster layer and the reinforced surface.

The plaster mesh is stretched to level the walls with plaster if there is no confidence in the strong adhesion of the plaster to the base or the layers exceed 20 mm.

Before stretching, holes are drilled under the ceiling every 20-30 cm. Wooden plugs are driven into them (furniture dowels of suitable diameter are very good for this). Nails are driven into these plugs. Then a piece of mesh is cut to fit the height of the room. It is hung on nails with a curve towards the inside of the room, this will make it easier to level it. The nails are bent, and then holes are drilled through the holes in the mesh at intervals of 20-30 cm in height and length. They hammer the plugs into them and use nails to press it against the wall. Be sure to secure all edges. If the mesh in some places moves away from the wall, then additional fastening is made in them. When drilling holes, it is necessary to take into account that there may be pipes and wires in the walls. Usually they are 10-20 cm from the ceiling or corner. If there are pipe outlets on the wall, then it is better not to make holes along the horizontal and vertical axes relative to them.

The amount of mesh is easily adjusted based on the area of ​​the surface to be plastered and the width of the mesh. Corks and nails are needed approximately 25 pieces per 1 square meter.

Is plaster reinforcement required? - apartment renovation library.

Considering that in Russia it is customary in most cases to carry out renovation work to European standards and this type of repair presupposes, first of all, its compliance with European standards, in the future we will also point out the building rules adopted, in particular, in Germany in relation to work on reinforcement of plaster.

Reinforcement of the internal plaster layer is usually done using plaster mesh. Its purpose is to reduce the impact of the underlying base on the finishing layers and minimize the risk of cracks associated with the mobility of such layers.

Plaster mesh not applicable to increase the adhesion strength of the plaster layer to the base. To do this, you should use special solutions such as “Betokontakt” (see also materials for finishing work).

The use of such a grid is not directly provided for by the current Russian building regulations. In turn, European standards, although they do not necessarily require reinforcement of the plaster layer, indicate that the use of plaster mesh is possible in cases where there is a need to reduce the risk of cracks in the plaster layer. However, reinforcement of the plaster layer, within the meaning of European building standards, cannot serve as a means to prevent the formation of cracks caused by the influence of structural processes (for example, deflection of floors, shrinkage, creep of load-bearing structures or their deformation caused by temperature changes) (see DIN V 18550 p. 4.3 paragraph 2 and paragraph 6.3).

Reinforcement of surface finishing layers, among other things, reduces visibility cracks that, due to various types of processes, appear in the underlying layers.

In accordance with the thickness of the plaster layer made with gypsum mixture, the average is 15 mm (which corresponds to European construction regulations). This plaster is applied to one layer. In the case of reinforcing the plaster layer, the mesh is installed(recessed) into a freshly applied and leveled plaster solution to a height of at least 2/3 of the entire plaster layer (for example, to a height of at least 10 mm with a total thickness of the plaster layer of 15 mm) without the formation of folds and is covered even before the formation of a crust on the surface of the main layer a subsequent layer of plaster, having a height of no more than 1/3 of the total thickness of the layer (technology of applying “wet layer on wet base” or “wet on wet”) - thus, virtually all plastering work is carried out in one layer.

The plaster mesh is laid with overlap not less than 100 mm (in places where one structural element adjoins another - not less than 200 mm).

In most cases, reinforcement of plaster on the surface of walls is not carried out continuously, but only at the junctions of various finishing surfaces and structural elements. When applying a plaster layer to the ceiling surface, it is recommended to apply reinforcement over the entire area of ​​such a layer.

When covering the surface of walls with tiles, reinforcement of the plaster layer is not performed. At the same time, the thickness of the plaster layer in accordance with European standards is 10 mm versus 15 mm, provided for subsequent gluing of the surface or covering with paint layers.

Plastering work should be carried out under the condition that massive the moisture content of the underlying base is no more than 8% (Russian SNiP) or the residual moisture is no more than 3% (V DIN, Germany).

Our Austrian colleagues at one time conducted detailed research and found that in the case of using gypsum plaster in new buildings subject to structural deformations (for example, in the form of shrinkage), it is possible to reduce the risk of cracks on the surface of the plaster, provided that the plaster is applied in a thick layer 20 mm and its reinforcement with plaster mesh.

Currently, there are stacks of actual plastering and painting. The first has a cell measuring 5 x 5 mm and is used to reinforce the plaster layer. The second has a smaller cell - 2 x 2 mm and is used when applying putty. In addition, the so-called “spider web” - fiberglass, which is also used to reduce visibility cracks that may form in the underlying layers.

You may find it useful:

• Stages of renovation in an apartment.
• Types of apartment renovation.

Reinforcement of plaster with metal mesh

When plastering walls and ceilings, you have to deal with strong irregularities and protrusions. When leveling, a thickened layer of plaster appears in places, which can swell and come off over time. To prevent this from happening, you need to use reinforcement. It is recommended to take such measures when the thickness of the plaster is more than two centimeters and on hard surfaces. What materials can be used for this? Expanded, welded and woven metal meshes with a fine mesh are usually used. There are also plastic plaster mesh, which are cheaper, but less durable because... are corroded more quickly by aggressive plaster. During installation, such a mesh sags and becomes askew, so experience is required. Metal mesh has a more rigid and, at the same time, elastic structure and is easy to install.

Galvanized expanded metal mesh is ideal for the plaster frame and to prevent the appearance of microcracks when the foundation settles. Judge for yourself: it is elastic and fits well to the wall, repeating its geometry, durable and has no welds, protected from corrosion, and lightweight. The production of expanded metal mesh is waste-free, so it has a low price. It is made by cutting and simultaneously stretching a galvanized sheet of iron into diamond-shaped cells arranged in a checkerboard pattern. This mesh is durable, easy to install and inexpensive.

To attach the mesh to the surface you will need dowel nails, a hammer drill, tie wire, beacons and metal scissors. The surface must be cleaned of dirt and grease and primed. It is important that the mortar sticks to the wall, otherwise the plaster along with the mesh will fall behind and sag. We cut a piece of mesh to the height of the wall and fasten it with dowel nails from bottom to top. In multilayer heavy systems, the entire load falls on the dowels and mesh, and this must be taken into account when choosing them. It is convenient to fasten the mesh with wide washers or two-centimeter sections of the remaining beacon. You can buy special galvanized mounting tape or punched paper tape and cut it into pieces of suitable length. Some people simply do not drive the nails in completely and bend them, fixing the mesh. There is also a way to fix the plaster mesh with knitting wire: we hammer in the dowels not completely, tie the caps with wire in the shape of the letter Z and then finish them off. With any method, fastening is done with a certain step. There are 20-16 dowel nails per 1 square meter. We stretch the mesh well and press it as tightly as possible against the wall; bulges of more than 1 cm are unacceptable. At the joining points we overlap the mesh. The corners of door and window openings must be additionally secured with pieces of mesh measuring 300x500mm. Then we set up the beacons.

After this we plaster the wall. Apply the first layer with a more liquid solution, using sharp movements. This is necessary so that the solution sticks well to the wall through the small mesh cells. After this we leave it to dry. Apply the second layer with a thicker solution and stretch it from bottom to top.

It is up to you to decide whether to use a reinforcing frame for plaster or not. A layer of plaster up to two centimeters does not need to be reinforced. But some claim that even with a layer of five centimeters, no cracks or detachments appeared. However, you should not experiment. Often such experiments backfire. The plaster shrinks and the foundation settles. and the walls are cracking. And reinforcement gives the surface elasticity and mechanical strength. If all technological standards are observed, a reinforced plastered wall is quite strongly protected.

Is plaster reinforcement required?

Considering that in Russia it is customary in most cases to carry out repair work on conditions and this type of repair assumes, first of all, its compliance with European standards, in the future we will also point out the building rules adopted, in particular, in Germany in relation to work on reinforcement of plaster.

Reinforcement of the internal plaster layer is usually done using plaster mesh. Its purpose is to reduce the impact of the underlying base on the finishing layers and minimize the risk of cracks associated with the movement of such layers.

The use of such a grid is not directly provided for by the current Russian building regulations. In turn, European standards, although they do not necessarily require reinforcement of the plaster layer, indicate that the use of plaster mesh is possible in cases where there is a need to reduce the risk of cracks in the plaster layer. However, reinforcement of the plaster layer, within the meaning of European building standards, cannot serve as a means to prevent the formation of cracks caused by the influence of structural processes (for example, deflection of floors, shrinkage, creep of load-bearing structures or their deformation caused by temperature changes) (see DIN V 18550 p. 4.3 paragraph 2 and paragraph 6.3).

Reinforcement of surface finishing layers, among other things, reduces visibility cracks that, due to various types of processes, appear in the underlying layers.

In accordance with SNiP, the thickness of the plaster layer made with gypsum mixture is on average 15 mm (which corresponds to European construction regulations). This plaster is applied to one layer. In the case of reinforcing the plaster layer, the mesh is installed(recessed) into a freshly applied and leveled plaster solution to a height of at least 2/3 of the entire plaster layer (for example, to a height of at least 10 mm with a total thickness of the plaster layer of 15 mm) without the formation of folds and is covered even before the formation of a crust on the surface of the main layer a subsequent layer of plaster, having a height of no more than 1/3 of the total thickness of the layer (technology of applying “wet layer on wet base” or “wet on wet”) - thus, virtually all plastering work is carried out in one layer.

The plaster mesh is laid with overlap not less than 100 mm (in places where one structural element adjoins another - not less than 200 mm).

In most cases, reinforcement of plaster on the surface of walls is not carried out continuously, but only at the junctions of various finishing surfaces and structural elements. When applying a plaster layer to the ceiling surface, it is recommended to apply reinforcement over the entire area of ​​such a layer.

When covering the wall surface with ceramic tiles, the plaster layer is not reinforced. At the same time, the thickness of the plaster layer in accordance with European standards is 10 mm versus 15 mm, provided for subsequent wallpapering of the surface or covering with layers of paint.

Plastering work should be carried out under the condition that massive the moisture content of the underlying base is no more than 8% (Russian SNiP) or the residual moisture is no more than 3% (V DIN, Germany).

Our Austrian colleagues at one time conducted detailed research and found that in the case of using gypsum plaster in new buildings subject to structural deformations (for example, in the form of shrinkage), it is possible to reduce the risk of cracks on the surface of the plaster, provided that the plaster is applied in a thick layer 20 mm and its reinforcement with plaster mesh.

Currently, there are stacks of actual plastering and painting. The first has a cell measuring 5 x 5 mm and is used to reinforce the plaster layer. The second has a smaller cell - 2 x 2 mm and is used when applying putty. In addition, the so-called “cobweb” - fiberglass, which is also used to reduce visibility cracks that may form in the underlying layers.

When, as a rule, a “web” is used. In this case, reinforcing putty layers with painting mesh is not used in most cases. However, such work can be performed additionally at the request of the customer or if there is such a task in the project.

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