How to apply mesh under plaster. The use of plaster mesh. Surface preparation for plaster

When finishing ceilings and walls, plaster and mesh under plaster are often used.

Plaster may not always lie perfectly on the surface. In order for the plaster layer to fix better, you can use a plaster mesh.

Previously, wooden shingles were used for these purposes (for wooden surfaces), brick was plastered without preparation - its roughness and seams were a sufficient condition for good adhesion of the plaster layer to the wall.

Scope and characteristics

The mesh under the plaster is used to ensure that the plaster layer holds firmly. The fact is that even with a carefully prepared surface for plastering, the solution can sometimes not lie as it should. This can happen if some errors are made during plastering: non-observance of proportions, temperature and humidity levels in the room ...

In order to avoid such errors, it is necessary to use plaster meshes, thanks to which the negative consequences of plastering are significantly minimized. These nets are designed to take on the load that may result from misuse of the space.

Grids are used to reinforce walls before painting (pasting with wallpaper). The mesh gives the plaster the greatest strength, increasing the service life. Especially appreciated is the use of grids for walls with significant defects, when it is necessary to apply plaster in a thick layer.

Before you buy a grid for plaster, you need to choose the one that is suitable for a particular job.

Mesh types

There are a lot of types of mesh for plaster. When choosing the one that is needed for certain work, you need to focus on the features of the type of grid and the size of its cells.

There are different types of mesh:

• Masonry grid. It is made from a polymer material. The size of each cell in the grid is 5x5 millimeters. Used for brickwork.

• Grids station wagon are made of polyurethane. Used for plastering and finishing works. There are types of station wagon grid: small - cell size 6x6, medium - 13x15 and large - 22x35.

• Fiberglass. Manufactured from fiberglass, which is specially processed. Cell size - 5x5 mm. This mesh is particularly durable and resistant to various temperatures and chemical attack. Has wide application./li>

• Plurima. This mesh is made of polypropylene. Cell size - 5x6 mm. Possesses chemical inertness. It is applied to internal and external finishing works.

• Armaflex. It is made of polypropylene and has reinforced knots. The cell size is 12x15. It is used when plastering the surface with a thick layer.

• Syntoflex. Also made of polypropylene. Cell sizes 12x14 and 22x35. Suitable for interior and exterior decorating.

• Steel mesh. The basis of this grid is steel rods, which are soldered at the nodes. A wide range of cell sizes is available.

• Metal grid. Cell sizes vary. It is used only for finishing work inside the building.

• Galvanized mesh. It is made of galvanized rods, which are soldered in knots. Cell sizes may vary. Differs in the high durability and durability. It is applied to external and internal finishing works.

Which one to choose?

When choosing a plaster mesh, you need to pay attention to what type of work you are going to perform. That is, you need to know the thickness of the layer of future plaster. Namely:

• With the required thickness of the plaster layer up to 20 mm, you can not use the mesh at all.

• In the presence of rustication and the required thickness of the plaster layer is from 20 to 30 mm. The most acceptable would be the use of fiberglass mesh.

• With a plaster layer thickness of 30 mm. A metal mesh is required.

• If it is necessary to finish an uneven ceiling, in which the height differences are from 50 mm, it is better to abandon plastering altogether, replacing the plaster with a suspended or stretch ceiling. This will make it much easier and cheaper.

Make your choice, and let all the finishing work be done perfectly.

Plaster on the grid is an effective way to rough finish the walls. But what is the essence of this method, which grid to choose and in what cases should it be used? Next, we will try to answer these and some other questions related to the application of plaster on the grid.

Why do you need a plaster mesh

As you know, plaster is a versatile material, as it can be applied to almost any surface. However, not all of them have sufficient adhesion with the plaster solution, as a result of which the finish can peel off and crumble. Moreover, sometimes this process begins almost immediately after the repair.

Such surfaces, first of all, include brick and wooden walls. Accordingly, the use of a plaster mesh will prevent this process. In addition, this material is used for another reason - it allows you to reduce cracking of the surface, which is especially important if the finish is done in a thick layer.

Types of mesh and their application

To date, there are several types of grids on the construction market. First of all, they differ in the material from which they are made.

For plaster, the following types can be used:

• fiberglass;
• Metal.

If the surface of the wall is sufficiently even and the plaster will be applied in a thin layer, then a fiberglass reinforcing cloth is sufficient to strengthen the finish. But if the walls are crooked and the thickness of the plaster is more than two centimeters, then a metal mesh is indispensable.

Unlike fiberglass, metal meshes come in different types:

• Woven;
• Wicker;
• Welded;
• Cut-and-draw.

Now consider the features of each type of material, which will allow you to make the right choice when purchasing it.

Woven

This mesh is a fairly flexible fabric made of durable thin wire. It is sold in large rolls, making it quite convenient to transport.

Most often, it is also the performance of internal work. The only thing when choosing this material, you need to pay attention to the cross section of the cell. Woven plaster mesh 10x10 mm is the best option.

Advice! A prerequisite for the use of this canvas is the presence of a zinc coating on it.

Wicker

Another such material is called a chain-link mesh. As it is not difficult to guess, it is performed by weaving wire.

Most often, this plaster mesh has a cell cross section - 20x20 mm. Most often it is used to strengthen large areas of walls and facades. The material is also sold in rolls, like the previous canvas.

Advice! If plastering is performed with a clay-based mortar, then a 50x50 mm plaster mesh is used for these purposes, i.e. with a large cell cross section.

Welded

Welded mesh is made by joining wire by welding. Such a canvas has symmetrical square cells.

Most often, the wire for its manufacture is galvanized or treated with a special polymeric protective composition. Usually this material is used for plastering walls subject to strong shrinkage. Thus, welded mesh can be used when plastering new buildings or buildings that stand on moving soils.

expanded metal

TsPVS plaster mesh is distinguished by a rather complicated manufacturing process. It is based on a metal sheet, in which holes are made on a special machine. After that, such a metal is stretched, as a result of which it turns into a grid.

The cells look like diamonds and are staggered. This material is used only in cases where a slight consumption of plaster per square meter is expected.

TsPVS is also sold in rolls one meter wide and of different lengths. As a rule, the price of expanded metal mesh is the highest.

The technology of applying plaster on the grid

Foundation preparation

Despite the use of a mesh, the base must still be carefully prepared before plastering:

• First of all, the old coating is peeled off the wall - paint, plaster, etc.
• All flaking and crumbling areas must be removed.
• Then the base is cleaned of dust. If there are traces of mold or fungus on the surface, then the wall must be cleaned with a metal brush.
• A layer of primer is applied to a solid and clean surface of the wall, which improves adhesion, strengthens the base and protects the wall from the effects of microorganisms.

Mesh installation

After the base has been prepared and primed, the plaster mesh can be installed.

Work is carried out in the following order:

• The first step is to measure the height of the wall to be plastered.
• Next, you need to unfold the roll and cut the sheets of the required size with special scissors for metal.
• After all the pieces are prepared, they should be attached to the wall. Plaster mesh installation is usually done with self-tapping screws or construction nails. The sheets should overlap by 10 cm. In order for the mesh to be securely fixed, it is necessary to use washers or perforated galvanized tape.

Note! When installing the mesh, you should pay attention so that it does not sag and does not lag behind the wall by more than 1 cm.

I must say that in most cases, with internal and, a plaster mesh of 5 - 5 mm or with cells of 10 by 10 mm is used, with the exception of some cases, which are indicated above.

Installation of beacons

After the grid is securely fixed to the wall, it is necessary to install beacons with your own hands, thanks to which a flat surface of the walls is achieved. For these purposes, a plaster profile should be used.

Installation is carried out in the following order:

• First of all, the vertical position of the extreme beacon is set using two self-tapping screws. The position of the profile should be controlled using the building level.
• Then the profile is fixed on self-tapping screws with a gypsum mortar, which quickly hardens.
• After that, an extreme lighthouse is installed on the other side of the wall. In order for the rest of the guides to be located in the same plane, a thread can be pulled between the extreme beacons.
• Next, intermediate profiles are mounted with a step less than the length of the rule, which will allow the tool to rely on them when leveling the wall.

Applying plaster

After installing the beacons, you can proceed directly to the plastering.

The instruction looks like this:

• Immediately before finishing, you need a creamy consistency.
• Then the first plaster layer is applied, which is called a spray. The composition is thrown onto the walls with a trowel or ladle. In the process of doing this work, some effort should be applied so that the mixture sticks to the surface, and does not slide down.

The spray layer should be about 1 cm.

• After the spray has set, a thicker solution should be prepared and applied to the walls with a trowel. If the required thickness is reached, then the surface must be leveled using the rule. To do this, the tool should be pressed against the beacons and stretched from the bottom up, which will wipe the solution and remove its excess.
• When the plaster sets, you need to remove the beacons and repair the remaining traces with a solution.
• The final step is to align the corners. The joints between the wall and the ceiling, as well as the internal corners, are leveled with an angled spatula. Perforated metal corners are used to finish the outer corners.

This completes the plastering process, now the mesh and plaster form a durable coating on the wall that can last for many years.

I must say that we considered the installation of a metal mesh. If a fiberglass cloth is used, then it is usually glued to the wall directly during the plastering process.

Conclusion

Having dealt with the types and types of grids for plaster, as well as their purpose, it will not be difficult to choose the right material. However, in order to achieve a positive effect from its use, it is necessary to follow the finishing technology, which is described above.

For more information on this topic, see the video in this article.

Good afternoon Anule,
We strongly recommend that you use a reinforcing mass before applying the plaster. It is in the reinforcing mass that the reinforcing mesh should be embedded, and after that the plaster should be applied. Otherwise, cracking of the plaster cannot be avoided.

I want to offer one of the options for the company's technology for plastering the facade STO AG:

1. Preparation of the base
After cleaning the facade from dust, primer is applied StoPlex W. The soil regulates absorbency, strengthens the surface and increases the adhesion of the surface to the reinforcing mass. StoPlex W contains additives that prevent the appearance of fungi and mold.

2. Application of mineral reinforcing mass StoLevel Uni.
After protecting window openings from contamination with plastic film, a mineral-based reinforcing mass is applied to the primed surface. StoLevel Uni. StoLevel Uni based on high quality white cement reinforced with fiber fibers, which has the advantage of increased resistance to mechanical and thermal stress. Designed for leveling the surface and reinforcing the facade of the building. One of the properties StoLevel Uni - high vapor permeability.
A fiberglass reinforcing mesh is embedded in the reinforcing mass Sto-Glasfasgergewebe, according to the principle: reinforcing mass + glass mesh + reinforcing mass. Sto-Glasfasgergewebe alkali resistant. I do not advise you to neglect fiberglass.

3. Priming of the reinforcing mass.
application of an intermediate layer StoPrep Miral(recommended).

4. Application of mineral plaster Sto-Strukturputz . Sto-Strukturputz used as a facade decorative coating. According to the type of surface structure, it is divided into three types: scratched “fur coat”; furrowed "bark beetle" and modeled.
Sto-Strukturputz as well as StoLevel Uni has high vapor permeability.
over Sto-Strukturputz, as well as over any other mineral solution, it is necessary to apply a finishing coloring coating. If for you one of the main criteria for choosing materials is high vapor permeability, preference should be given silicate or silicone paints. It is in this group of materials that the vapor permeability index is the highest.

5. Painting the surface with silicate facade paint StoSil Color, or silicone facade paint StoSilco Color. Alternatively, you can consider a self-cleaning exterior paint. StoLotusan Color silicone based.
Peculiarity StoLotusan Color– in the presence of high vapor permeability, the surface absolutely water-resistant. Particles of dirt that have settled on the facade of the building during the drought roll down, carried away by raindrops. Drops of water do not linger on the facade, which eliminates the formation of dirty smudges on the surface of the facade.

I described the best solution, taking into account your requirements for high vapor permeability. In any case, in order to determine the most suitable solution for you, you need to familiarize yourself with the object on site. According to the group's experience StoAG before the start of work, we recommend inviting our specialist to conduct master classes on working with materials of the brand Sto directly at the construction site. Departure of the technologist is free of charge.

If our offer is relevant for you, for more specific information, you can contact me via PM.

Too smart. The base reinforcing layer is not necessary here, especially since you won’t be able to level the base with it ... if you advise, then first offer a penetrating primer, then a vapor-permeable plaster for plastering cellular concrete, if you have it, of course, and only then a base reinforcing layer with fiberglass mesh. The use of mineral plaster in private construction is no longer permissible, it is only for municipal and Khrushchev houses, for private houses silicate, silicone, or silicate-silicone decorative plasters, painted in volume with high vapor permeability, friction resistance and abrasion .. mineral water of the last century, but at home on sale. it is not necessary to fully post the instructions, but you are very diligent

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 passed the shrinkage stage, but in a number of works it is indispensable. Cell sizes, diameter and base are different, in each 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 deformations of the finish. Its installation at times reduces the influence of mechanical, humidity and temperature influences and increases the quality of adhesion of solutions to the bases. Plastering of walls on a grid (and other surfaces) is considered mandatory when:

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

Types of grids, 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 web, are divided into thin and flexible woven (with a small wire diameter), woven, welded (the most rigid, recommended for high base mobility) 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 grid for plaster, it is worth choosing a protected type, with a zinc coating, it better withstands the alkaline effect of cement and is less susceptible to corrosion.

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

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 to reinforce thin-layer plaster (up to 20 mm), medium (13 × 15) is advised to buy when strengthening coatings up to 5 cm thick, including loaded ones, large (22 × 35) - when working with large surfaces and uneven facades. This group includes many subspecies and brands: Plurima (based on polypropylene with high chemical inertness), Sintoflex (heavy-duty and geometrically stable brand), STREN (recommended for use under the influence of aggressive environments), Armaflex (reinforcing any type of masonry, including uneven). The cost per square meter depends on the quality, chemical inertness and strength of the plastic and varies from 11 to 110 rubles.

What grid to use and in what cases?

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

It is better not to save on external surfaces; these areas require varieties coated with zinc or impregnated with alkali-resistant compounds. To exclude doubts, the material is checked by immersion in a soapy solution for several days, quality products do not spread and do not change color. When buying facade meshes, attention is paid to the value of the breaking load. On flat areas, a canvas with 1800 N and above is used, on curved areas - within 1300-1500.

When finishing the interior, the same rules apply - a thick-layer coating requires reinforcement with metal, a thin-layer one - with fiberglass or polypropylene. The latter type is also used as a masonry one: an elastic web with 5 × 5 cells is placed between bricks or blocks and increases the adhesion of rows and products. The recommended density range for synthetic meshes for internal plaster is 110-160 g/m2, which is enough to ensure crack resistance and keep the layer within 2-3 cm. adjoining the ceiling, reinforcing mastic roofs, serpyanka is well suited - a thin fiberglass with a cell size of 2 × 2 mm and a density in the range of 45-60 g / m2.

Do-it-yourself grid mounting nuances

The metal variety weighs the most and needs to be securely fixed with screws or nails. It is degreased (galvanized is simply washed with water or wiped with a rag) and cut with special scissors into pieces of the desired size, taking into account the obligatory entry into neighboring areas by 10 cm. In some cases, holes for dowels are prepared in advance, the step is 25-30 cm, on average m2 takes 16 fasteners. The edges, if possible, are fixed with a mounting tape (when working with coarse-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 closed with a mixture, it is important to choose the correct cross section and method of connecting the wire, it is impossible to reduce the coating thickness below the recommended value.

When working with fiberglass and polypropylene meshes for plaster, the mortar itself or self-tapping screws and screws can act as fixing materials. In the first case, the canvas is placed in the middle of two layers; to increase the density, it is better to unwind it directly on the spot, and not cut it into separate pieces (the exception is the foam plastic finish, where segments are better suited). Plastered in the direction from the middle to the edges.

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

But a more reliable and correct option is to fix the dowels on 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 mounting beacons. The first layer of the solution is placed along the width of the product, after laying it, they proceed to the next one, tracking the approach to each other by 10-15 cm. 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 meshes, otherwise they depart 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

The popularity of plaster coatings is due to several reasons. This material is easily applied to any surface, it is resistant to mechanical stress, withstands temperature extremes well, is durable and economical.

Types of plaster solutions

For different types of plastered surfaces, different plaster compositions are used. Lime or cement-lime mortar is used for finishing brick walls, and cement mortar for concrete surfaces. Such solutions include certain additives and fillers required by the operating conditions and the purpose of the plastered surfaces. Without them, the solution will turn out to be fragile and the surfaces treated with a low-quality solution will quickly become covered with cracks.

Plaster mesh installation

Metal mesh should cover concrete walls with strong irregularities and protruding places, areas of their junction with wooden and metal surfaces, as well as surfaces that require a large thickness of the plaster coating.

The use of a plaster mesh provides the rigidity of the structure necessary in these cases. Such a mesh is made of round wire rod or woven from wire.

With significant surface irregularities, in order to make the plaster of the walls along the grid of high quality, a frame is installed. Laths are nailed to the wooden walls, to which the mesh is attached with nails or staples. Steel pins are mounted on brick and concrete walls, to which a mesh is attached with wire. The joints of the walls and the protruding corners of the partitions are sheathed with mesh strips.

On large structures, beams, tees, channels, etc. are used for the frame.

The frame is necessary for high-quality fastening and tensioning of the mesh. It is evenly and tightly stretched, the mesh joints are firmly woven with wire. This is done to ensure that the entire structure is rigid and motionless.

Plastering walls on a grid without a frame

For small flat surfaces, plastering walls on a grid without a frame is acceptable, which is much simpler and cheaper. The mesh is attached to beams and protruding structures with a knitting wire with tension and fastening on dowels. To flat surfaces - with a mortar or a construction gun.

The grid should have small cells and not sag after installation. To protect against corrosion, mesh and metal fasteners, if they do not have a protective coating, must be treated with oil paint, bituminous varnish or cement laitance.

The main rule when plastering on a grid is to surround the grid with a poured mixture from all sides. When this condition is met and high-quality plaster is used, a solid monolithic reinforced mortar slab is formed as a result.