37764 0

Facade finishing is one of the most important construction operations. Exterior wall cladding is exposed to precipitation, freeze/freeze cycles and harsh ultraviolet rays. Such difficult operating conditions put forward increased demands on the quality of the finish. Eliminating defects on facade walls is very expensive and time consuming. We will have to mount scaffolding, wait for good weather, remove construction debris. To prevent the occurrence of unpleasant situations, you need to take all measures to prevent them.

Finishing of front walls is carried out by various materials and technologies. The reinforcing stack is used in two cases.

To improve the performance of the plaster layer. For such purposes, it is better to use a metal mesh made of galvanized wire.

All-metal mesh

The fact is that among the many advantages of foam blocks, it is necessary to pay attention to one very significant drawback - low physical strength. Another problem is that concrete blocks begin to crumble when freezing / freezing in conditions of high specific humidity. As a result, cement plaster begins to peel off with all the negative consequences.

The reinforcing mesh allows the plaster to adhere to the wall surface. The talk that such a grid should be used with a large thickness of the plaster, that due to this, cracks do not appear on the plaster, have only a partial confirmation. First, there are simpler and cheaper methods to prevent cracks from appearing in thick plaster. The simplest is to throw the solution in a thin layer in several stages. Secondly, it is possible to increase the adhesion of the mortar with the facade wall due to a slight increase in the amount of cement in the mortar. If this is not enough, then a spray of cement milk is done.

To protect the insulation of facade walls from destruction. The reinforcing facade mesh is used during the finishing of foam insulation boards.

Not to improve the fixation of the adhesive to the surface of the expanded polystyrene and to prevent cracks, as some "sofa" builders write, but for mechanical protection.

Why do we say so? The surface of expanded polystyrene is protected from the negative effects of ultraviolet rays and, oddly enough, from damage by birds. For some unknown reason, birds are very fond of pecking foam, if left unprotected, then soon many large and small depressions will appear on the surface. Conclusion - polystyrene foam must be closed. The cheapest and most reliable method is to use glue.

By the way, the advertising characteristics of manufacturers of plastic reinforcing meshes “they are not afraid of UV” do not affect their actual performance in any way. The fact is that even the thinnest layer of glue or other cement-sand mixture does not completely transmit ultraviolet rays. Why should a consumer pay for properties they don't need? And one more nuance. Most often, builders fix the reinforcing mesh on the entire wall. We think that this is done either out of ignorance of physical properties, or a desire to earn more. We recommend using a reinforcing mesh to a height of 1.5–2.0 meters, there is no need to go higher. No one will damage the finish screed on foam plastic so high. Mechanical damage occurs due to various impacts, careless chores near the facade wall, etc.

Types of facade reinforcing meshes

Facade reinforcing meshes are made of galvanized wire or polymers. The former are used for facade plaster, and the latter for universal use.

Name	Cell sizes, mm	Roll dimensions, m	a brief description of	Approximate cost, rubles
Safety	2×2	1×50	Production material - fiberglass, used to reinforce plaster near door and window openings, to align the joints of insulation boards	900
OXISS	5×5	1×50	The mesh has a reinforced protection against alkalis, can withstand significant dynamic and static forces for a long period of action.	1050
Facade fiberglass mesh	5×5	1×50	For holding plaster of concrete facades and insulation boards. Withstands a tensile load of at least 1400 N/cm.	1400
STREN C5	22×35	2×25 2×50	Withstands rough and fine facade plaster up to 5 cm thick.	2750
KREPIKS Facade 1300	4×4	1×50	Fiberglass, there is protection against alkalis and ultraviolet radiation.	1560
KREPIKS Facade 1500	5×5	1×50	Reduces the likelihood of cracking due to thermal linear expansion	1970
KREPIKS Facade 2000	4×4	1×50	For reinforcing finishing plasters during the finishing of the insulation layer of the facade	2300
	6×6, Ø 0.6 mm	1x15	Increased strength, resistant to precipitation and sunlight	1110
	10×10, Ø 0.8 mm	1x15	For rough facade plasters with a thickness of 3–5 cm	1330
	25×25, Ø 1.0 mm	1×25	For strengthening facade walls, universal use. Hot dip galvanized wire, minimum coating thickness 20 µm	1770
TsPVS grid	20×20, Ø 0.5 mm	1×25	All-metal expanded metal. It has an increased area of ​​contact with a solution of facade plaster.	580

Modern facade mesh

Prices for construction reinforcing meshes

Construction reinforcing mesh

Metal mesh fixing technology

Metal meshes are used only for cement-sand facade plasters, foam insulation is not finished with them. The reason is the small thickness of the screed on foam boards. And the metal mesh cannot be aligned with such accuracy, it must be pressed with a thick layer of mortar. The metal facade reinforcing mesh is able to withstand great efforts, it is used if it is necessary to apply a thick layer of plaster on an uneven base.

The fixation algorithm has several features, the implementation of which guarantees the expected effect. You can lay the grid in both vertical and horizontal stripes. For the strength of the plaster, this does not matter, decide for yourself how it is more convenient for you to work. How to properly fix the metal mesh to the facade wall?

Step 1. Take the dimensions of the wall, cut the metal mesh along them. Select the cutting tool according to the wire diameter. Universal tool - scissors for metal.

If they are not there, then a thin mesh with a wire diameter of up to 0.8 mm can be cut with ordinary scissors. True, after that these scissors will have to be sharpened, they will no longer cut the paper.

Prices for construction scissors for metal

Step 2 The metal mesh can be fixed with dowels, the length of the hardware should provide a strong fixation. For facade walls made of foam blocks, ordinary nails 80–90 mm long can be used. They are easily hammered into blocks with an ordinary hammer, working with them is much faster and easier. Nails are much cheaper than dowels, and the quality of fixation is no different. Use dowels only on brick or concrete facade walls.

Step 3 Using an electric drill with a hammer drill, drill the first hole for the mesh. The depth of the holes should be several centimeters greater than the length of the plastic part. Otherwise, it is impossible to insert the dowel to the desired depth - the hole is slightly filled with brick chips during drilling and reduces its effective depth. It is difficult to remove it from there, it is better to drill more.

Important. The height of the protruding part of the dowels should not exceed the thickness of the plaster. Follow this parameter on the entire area of ​​​​the facade wall so that during plastering you do not have to adjust the dowels.

Step 4 Drill holes in one line at a distance of about fifty centimeters, hang a net on each dowel. Pull it a little, do not allow large irregularities. The position of the line does not matter, it can be vertical or horizontal, depending on the method of attaching the reinforcing metal mesh.

Step 5 Check the position of the opposite edge of the grid, if it is uneven, then move the grid to adjacent cells.

Plaster mesh fastening - scheme

Step 6 Everything is normal - continue to fix the grid, install the dowels in a checkerboard pattern. Most metal meshes are one meter wide, you will need three rows of hardware to fix them.

Important. In places where two rolls overlap, install the dowels at a distance of approximately 10 cm from the edge. Two strips of reinforcing mesh will be hung on these dowels at the same time.

Step 7 In places of window and door openings, the mesh is cut to size. But there is nothing to worry about if you do not cut it off, but simply bend it. Just make sure that the edges of the bent sections do not protrude beyond the thickness of the plaster layer.

During the plastering of such a facade wall, the mortar must be applied in several stages. For the first time, the mass should be a little thicker than for the final alignment. Specific values ​​​​depend on several indicators and are determined individually, taking into account the practical experience of the master. The consistency of the mortar is influenced by the weather, the ability of the facade walls to absorb moisture, the linearity of the wall, the maximum parameters of the irregularities, etc.

Step-by-step instructions for fixing plastic meshes

The durability of its operation largely depends on the correct implementation of the recommendations for installing a plastic reinforcing mesh on a foam insulation. In all cases, do not rush, work carefully. We have already mentioned that there is no need to reinforce the entire wall in height, it is enough to protect only the lower vulnerable area. But these are our recommendations, if in doubt - protect the entire surface of the facade wall.

Any brand of glue is suitable for gluing the mesh. Read the instructions, it should have high adhesion with plastic materials. In most cases, a final layer of adhesive several millimeters thick is applied over the plastic reinforcing mesh. The final coating is done with facade paints or a thin layer of decorative plaster.

Step 1. Examine the surface of the plates. If they were fixed with dowels, then completely drown the caps and close the recesses. At the same time, you can close the slots, but this is not necessary. The fact is that the slots will automatically close during the application of the first layer.

Step 2 On the wall, draw a horizontal line along the height of the reinforcing layer. It will help to monitor the height of the application of glue. A thin layer of material dries quickly, and this not only causes an increase in material consumption, but also negatively affects the final leveling of the layer for painting.

Step 3 Prepare the adhesive according to the manufacturer's instructions. Always fill the container with water first, and then add the dry mix. This technology will greatly simplify the mixing process. Mixing can be done manually with a trowel or with a mixing attachment to an electric drill.

The second method is not only easier, but also more effective. You need to mix for several minutes, and then leave the mixture to stand for another 5-6 minutes. During this time, the moisture will be evenly distributed throughout the volume, the smallest dry lumps of glue will completely disappear.

Step 4 The glue is applied to the wall with a spatula, the longer it is, the smoother the surface is in the end. Professionals work with spatulas up to 70 cm in size, beginners can use shorter ones at first.

Practical advice. If you are just learning how to apply glue to the surface, then it is better to immediately get used to working with both hands. One gets tired - connect the second hand. Believe me, it is not so difficult, you just need to show a little endurance and patience.

Apply glue to the spatula with a trowel in the center of the tool. The quantity will be determined empirically. While applying the layer, hold the spatula at an angle to the foam plates, press with medium force. Achieve a layer thickness of approximately 2-3 millimeters. Do not prepare a large amount of surface at once; for beginners, two meters per dyne is enough. If you do not have time to fix the mesh, the glue will harden, you will have to remove the old layer and make a new one.

Step 5 Try on the location of the plastic reinforcing mesh. If it does not fit into the window opening, trim the material.

Step 6 Glue one end of the grid, align it horizontally to the length of the prepared section of the wall. Make sure that the mesh lies flat without distortions and bends, be guided by a pre-drawn line on the foam.

Practical advice. The mesh should overlap with about ten centimeters. You can find recommendations not to smear the place of overlap of one line with glue, but to do it simultaneously for two rows. We do not recommend doing this, it only complicates the work. Glue the first row of mesh immediately across the entire width, including the overlap. The second line will be glued on top of the freshly applied glue. This method simplifies mesh fixation and has a positive effect on quality.

Step 7 With your hand, press the mesh to fresh glue in several places, check its position again.

Step 8 With a spatula, begin to press the mesh to the surface of the insulation. Make sure that the glue of the first layer protrudes over the entire surface and evenly covers the mesh cells on the front side. If there are places with insufficient thickness of the adhesive, apply it again over the reinforcing mesh. Such omissions may appear in inexperienced craftsmen. Over time, you will learn to determine the optimal thickness of the glue by eye and there will be no more gaps. Smear excess solution on free surfaces. You should not try to immediately make the surface perfectly flat, but you need to strive for such a result.

Step 9 Give the glue time to dry. It is better to leave it overnight, it is recommended to finish the surface grouting the next day.

That's the whole technology, the surface of the facade wall is prepared for painting or finishing with other materials. We remind you once again that plastic reinforcing mesh on insulated facades is used not to prevent cracks on the adhesive surface, but to prevent mechanical damage to the foam. Keep this in mind when making a decision.

Prices for popular types of putty

Putties

Facade mesh for building protection

Compliance with safety regulations during construction work on multi-storey buildings is one of the main requirements for all developers. This is especially true of objects being built within cities. The facade mesh is fixed on the scaffolding and prevents construction debris and tools from falling onto pedestrian walkways. For such purposes, the cheapest of the plastic reinforcing meshes is used; after dismantling, it is suitable for direct use.

"Emerald" - a new grid for scaffolding

Question answer

Is it possible to repair exfoliated sections with a reinforcing facade mesh? It is possible, but it is better not to allow such situations. Unfortunately, in most cases, delaminations appear several months or years after finishing the insulated facade walls.

How is the repair done?

1. Revise the delaminated area. By hand, check the strength of the fixation of the mesh next to the exfoliated area. Prepare materials: glue and a piece of plastic reinforcing mesh. If the facade walls are painted, then you need to have the appropriate paint.
2. Pull the peeled mesh towards you and cut it around the perimeter with a sharp mounting knife. Be very careful not to damage the foam. If during cutting the sect continues to flake off - excellent. In this way, you remove the entire problem area; in any case, it would exfoliate over time.
3. Cut out a new mesh for the patch, the size should be slightly larger than the freed area for the overlap.
4. Remove a layer of old glue from the surface of the foam.
5. With a spatula, carefully remove the top layer of glue from the surface of the remaining mesh to the width of the new overlap. Apply the first layer of glue, sink the mesh into it and apply the second layer of glue.
6. After it dries, smooth it out. Pay special attention to the connection point. It should be as even as possible without sudden changes in height.

Everyone must have seen new houses with a cracked facade - thread-like cracks or generally fallen off pieces of plaster. The main reason for such consequences when finishing "wet facade" is the use of a mesh that does not meet the necessary requirements.

Currently, the building materials market offers a large selection of reinforcing mesh. As they say, eyes run wide - and white, and blue, and green, and yellow, and orange. But - the color of the grid does not affect its characteristics in any way, and each manufacturer paints them to their own taste or by order of large consumers. For example, you can make a grid even with your portrait - the main thing is that it meets the criteria that are necessary for its use.
Reinforcing meshes differ in density, breaking load, and alkali resistance - these are the main indicators that you need to pay attention to when choosing a mesh:

/duck) (n\5cm)

	Facade mesh parameters
	cell (mm)	density (gr\m²)
	5x5	145	1500/1500
	5x5	160	1800/1800
	4x4	165	2000/2000
	8x8	320	3200/3200

And now in more detail:

• Density - shows the mass of the grid and is measured in grams per square meter (g \ m²). The mesh can be used on the facade if its density is not less than 120 g/m². All grids with a lower density are only suitable for interior work.
• It must be understood that a grid with a minimum density will not work if the surface is plastered above 2 floors - as a standard, up to 5 floors, you can use a grid with a density of 145 g / m & sup2, and above - 160-165 g / m².
  Fiberglass with a density of 320 gr m², also called "anti-vandal", is used on basement floors to protect the plaster layer from mechanical damage and can serve as a basis for facing with stone or tiles.
• Inseparable from the density and such a characteristic as breaking load. It is measured in newtons per 5 centimeters (n/5cm). But it is important to know not the unit of measurement, but the load indicator - for a mesh with a density of 120 g / m² it is 1200-1300, 145 g / m² - 1500, 160 g / m² - 1800, 165 g / m² - 2000, 320 g / m² - 3200.
• Alkali resistance is an important indicator and the less the mesh is impregnated with a special compound, the more likely it is that in an alkaline environment, which is the plaster mortar, the mesh will simply dissolve and will not fulfill its function - to keep the plaster from cracking. This indicator is not written on the labels, so be sure to ask the seller for a product quality certificate.

Thus, when choosing a fiberglass mesh, we advise you to pay attention, first of all, not to the price, but to the presence of a technical certificate and a quality passport from the seller, because chasing cheapness can lead to big problems. And now let's estimate - one square meter of a "wet facade" with work will cost you 1,700 rubles. The price of one meter of a high-quality mesh that meets all conditions, even if the maximum is 50 rubles, a mesh of dubious "content" will cost 25 rubles. Doesn't it really affect the price of 1 m²? And when the plaster collapses in a year, the rework will cost 3,500 rubles per 1 m² (taking into account the breaking off of the destroyed layer). It is easy to calculate that with a scope of work of 2,00 m², while saving a grid of 25 * 200 \u003d 5,000 rubles, it turns out problem for 3500 * 200 = 700,000 rubles!

The presentation of the article is designed for those who are not the first to hold a spatula in their hands. Therefore, the technique for applying facade plaster or glue for polystyrene foam insulation is not explained in detail.

But photos of wet facades will perfectly demonstrate the difference in the technology of installing a plaster mesh in two ways, popular with craftsmen. This will allow you to calculate the feasibility of using one or another method on various parts of the facade.

Wet facade - plaster technology with fiberglass mesh

We are talking about light thin fiberglass mesh, which is sold in rolls. It comes in a variety of colors (usually blue, white or green). Its main property is resistance to solutions with an alkaline reaction. Unlike heavy welded metal meshes, which are used when plastering brick walls, fiberglass plaster mesh is successfully used in the finishing of facades insulated with polystyrene foam in a wet way.

By purchasing such a grid on the construction market, you can get a lot of useful tips and tricks from the "experienced" on how best to use it.

We demonstrate two ways of fixing a plaster mesh when reinforcing a wet facade.

Technological way of fastening plaster glass mesh (for pros)

The main steps for installing wet facades in this way.

We measure the length of the mesh from the roll, equal to the height of the wall section that is being prepared for plastering.

Mix the mortar mix according to the instructions on the bag. Instead, glue for polystyrene foam insulation boards is often used, which makes sense, since the adhesive mixture has the highest waterproofing and hydrophobic properties.

In the photo - just such a mixture.

We apply a layer of mortar, with a thickness of 2 to 5 mm. This must be done as quickly as possible, along the entire height of the wall segment. We level out small (up to 5 mm) differences in the level of the wall, but we don’t try to “display” the influxes - it’s too early yet.

Immediately apply the plaster mesh to the top of the wall, exposing it strictly vertically.

You need to press the fiberglass into the plaster layer with the widest spatula that can be found on the farm.

In one place, you need to make no more than 2-3 sweeping movements:

• press the grid;
• cover the grid in the "bald spots" with a thin layer of mortar;
• bring the area under the general level of the wall - align.

Pros and cons of the method

The disadvantages of the method:

• the cut mesh "gets underfoot" and is easy to get dirty;
• foam balls that have escaped from the insulation layer stick to the spatula and interfere with applying the solution;
• it is difficult for a beginner alone to quickly apply a plaster layer to the entire height of the wall and attach the mesh to the wet layer strictly vertically.

Advantages:

• dry mesh is laid without folds;
• easily pressed evenly;
• it is easier for many to bring the wall perfectly even using this method.

An alternative way to attach a plaster mesh (for beginners)

We cut off a segment from the mesh roll, the length of which will be equal to the height of the wall section plus 5-7 cm.
With a mounting stapler, we nail the mesh to the top of the wall or to the wooden part of the roof, using the allowance. The grid must be fixed in a strictly vertical position.

We mix the plaster solution. We apply a layer of plaster mixture 2-5 mm thick directly on the grid, trying not to leave empty spaces between the grid and the insulation. You need to start doing this from the highest point of the wall, moving down. Slightly leveling the differences in the walls, but we don’t worry about perfect smoothness yet.

It is not necessary to apply the solution to the entire height of the wall - you can repeat the following steps in 2-3 stages, moving from top to bottom along the wall.

Grasping the lower dry edge of the mesh, pull it towards you, completely separating it from the wall and the wet layer of mortar. Then release, without pressing, lay on top of the plaster.

Apply a small amount of mortar to a wide spatula and cover the mesh with it, moving your hand from top to bottom.

With wide arcuate movements, “smooth down” the wall to make it as even as possible for painting.

Advantages and disadvantages of the method

• during operation, the mesh gets a little wet and becomes heavy, which makes it difficult to remove it from the wall surface (stretches, forms waves, wrinkles);
• the output result may not please: it is difficult to achieve a mirror-like evenness of the surface, like a pro.

• pre-fixing the mesh allows you to break down the work into stages that can be completed by a beginner, even alone.

On the feasibility of two wet facade installation technologies

To master the technological method, first try sections of walls with a small height (under the windows, above the doorway). This will allow you to evaluate your strengths for applying the correct do-it-yourself wet plaster technology.

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 primarily implies its compliance with European standards, in the future we will also point to building regulations adopted, in particular, in Germany in relation to work on plaster reinforcement.

Reinforcement of the internal plaster layer is carried out, as a rule, with the help of plaster mesh. Its purpose is to reduce the impact of the underlying base on the finishing layers and to minimize the risk of cracks associated with the mobility 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 prescribe the reinforcement of the plaster layer without fail, however, indicate that the use of a plaster mesh is possible in the case when there is a need to reduce the risk of cracks in the plaster layer. At the same time, the reinforcement of the plaster layer, within the meaning of European building standards, cannot serve as a means to prevent the formation of cracks due to the influence of structural processes (for example, floor deflection, shrinkage, creep of load-bearing structures or their deformation caused by temperature differences) (see DIN V 18550 p. 4.3 paragraph 2 and paragraph 6.3).

Reinforcement of surface finishing layers, among other things, allows to reduce visibility cracks, which, due to various kinds 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 building regulations). This plaster is applied to one layer. In the case of reinforcing the plaster layer, the mesh installed(embedded) in 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 wrinkling and even before the formation of a crust on the surface of the main layer is covered a subsequent layer of plaster, having a height of not more than 1/3 of the total thickness of the layer (technology for applying "wet layer on a wet base" or "wet on wet") - in this way, virtually all plaster work is done in one layer.

Plaster mesh is laid with an overlap not less than 100 mm (at the junction of one structural element to another - not less than 200 mm).

Reinforcement of plaster on the surface of the walls in most cases is not carried out completely, but only at the interface of various finishing surfaces and structural elements. When applying a plaster layer on the surface of the ceiling, it is recommended to reinforce the entire area of ​​such a layer.

When facing the surface of the walls with ceramic tiles, the 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 against 15 mm, provided for subsequent pasting of the surface with wallpaper or covering with paint layers.

Plastering work should be carried out on the condition that mass the humidity of the underlying base is not more than 8% (Russian SNiP) or the residual moisture is not more than 3% (V DIN, Germany).

Our Austrian colleagues once conducted detailed studies 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 the form of a layer thick 20 mm and its reinforcement with plaster mesh.

Currently, there are stacks of proper stucco and painting. The first has a cell size of 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.

When, as a rule, a "cobweb" is used. At the same time, the reinforcement of putty layers with paint mesh is not used in most cases. However, such work can be carried out additionally at the request of the customer or if there is such a task in the project.

If you have any questions - write! We will try to answer them.