Insulating the facade in winter is difficult, but possible

External facade insulation systems are special structures that protect walls from the cold. Currently, there are several approaches to solving this problem, so the wide choice often leaves users with difficult choices.

There are many different systems for insulating facades on the market, each of which requires compliance with a number of norms and rules - from the selection of materials to installation.

Advantages of external thermal insulation systems

External insulation is considered the most popular - it has repeatedly proven its effectiveness. Internal thermal insulation, of course, also plays an important role in construction, but its advantages are incomparable to external ones. An external thermal insulation system has many advantages.

Reduced environmental impact

External insulation protects walls from overheating and hypothermia in any season of the year. As a result, the durability of the building increases, cracks do not appear on the facade, the plaster does not peel off, and the seams do not depressurize.

Exposure to moisture is eliminated: with external thermal insulation, the destructive effects of snow and rain are significantly reduced. There are also no ice formations in the thickness of the wall surfaces due to capillary moisture and its condensate.

Condensation protection

In the cold season, it is not uncommon for the temperature of the façade walls to drop below the “dew point”. As a result, condensation forms on the internal surfaces. The external façade insulation system prevents its appearance.

Smoothing or eliminating cold bridges

External facade insulation technology involves heat accumulation by the walls. As a result, the temperature of the coolant in the heating system decreases and the orientation of the building ceases to play a role - the temperature dependence disappears. “Bridges of cold” either smooth out or disappear.

Creating the perfect wall surface

Due to heat insulators, the wall structures of the building look smooth, and various defects inherent in stone and concrete are hidden by insulation.

High noise absorption

Most insulation materials are considered good sound insulators. Their use reduces noise coming from the street and creates a comfortable environment in the premises.

Durability

Although heat-insulating materials are constantly exposed to the environment, their production technology has long made it possible to create products that last for decades without losing their initial performance properties. 30-50 years is the average service life for any high-quality insulation.

The best way to insulate a house, how to choose the right material

When purchasing insulation for a facade, you must ensure that they are components of the same system. Sometimes when purchasing you will need the help of a professional, because the materials are not always sold as a single set, but must correspond to each other according to such characteristics as:

• vapor permeability;
• frost resistance;
• thermal expansion.

And also when choosing, you should take into account the chemical processes that will occur in a single system. Materials for insulation should be selected not only taking into account the type of frame. In this case, you need to make allowances for the climatic features of the region, architectural characteristics and technical purpose of the building.

The most common materials for facade insulation are mineral wool and polymer insulators

When insulating the façade of a house from the outside with foam plastic or other material, the continuity of the contour should be maintained. There should be no cracks, gaps or breaks on the façade through which moisture or frost would enter the frame

It is also important to maintain the vapor permeability of the system. Here the main rule is that each subsequent layer from the inside to the outside must have a higher degree of vapor permeability

This is done so that the walls can “breathe” and condensation does not form on the surface.

The cost of facade insulation will depend on what material is chosen for this. The most common are:

1. Mineral wool (mineral wool). Belongs to the group of fiber insulation materials. Most often made of fiberglass or basalt fiber.
2. Ecowool. Modern insulating material based on cellulose.
3. Group of polymer insulators. Polyurethane foam, polyurethane, expanded polystyrene.
4. Bulk radiators – expanded clay, vermiculite.
5. Natural traditional materials - dry leaves, reeds, straw, sawdust, pine needles, which can be used together with clay.

When insulating the facade of a house from the outside with polystyrene foam, the continuity of the contour must be observed; there should be no gaps, gaps or breaks

How to determine the thickness of the material for external wall insulation

Another key issue is to determine the heat transfer coefficient through the walls, which depends on the choice of specific thermal insulation material. Theoretically, the thicker the insulating material, the lower the ratio and therefore the better. In this case, it should be emphasized that the degree of insulation of mineral wool or polystyrene depends not only on their thickness (although this, of course, is of great importance), but also on the thermal conductivity coefficient. The indicator is also more favorable if its value is lower.

Insulation boards with a lower coefficient can be thinner while still maintaining good thermal conductivity.

This is important because the thinner the insulation, the smaller the recess will be for window and door openings.

Research has proven that exceeding a certain thickness of insulation does not lead to a significant improvement in the thermal insulation properties of the wall

Each house is individual, therefore, when choosing the thickness of insulation, not only climatic features are taken into account, but also the heat capacity of the floor covering, the specifics of the thermal insulation of the roof and basement, as well as the glazing area of ​​the house.

Today, when choosing an insulation material, you have to choose between three thickness standards (in centimeters):

• 50;
• 100;
• 150.

Calculating the layer thickness is easy. To do this, you need to calculate the initial wall thickness and estimate how much is missing from the norm, and then calculate how thick the facing layer should be. In addition to the thickness of the insulation, other criteria must be taken into account:

• plaster layer;
• external finishing;
• air gap.

Classifications

To protect the thermal insulation layer from destructive and pervasive atmospheric influences, various facade insulation technologies have been developed. Today, there are several options for external insulation systems for facades: wet and ventilated, siding, thermal panels, etc. Each technology has its own characteristic features.

Thermal insulation board

The efficiency of insulation work and the durability of the system largely depend on the façade slab. Facade insulation systems are made in two ways - contact and hinged. Contact methods - wet insulation, suspended methods - insulation of a ventilated facade.

If we consider the issue from the standpoint of cost, then the most economical and at the same time effective technology for insulating facades can be defined as thermal insulation systems with “wet” protection of each subsequent layer of insulation.

Contact method

Contact insulation is based on the use of special plates made from different raw materials. This includes mineral wool, polystyrene foam, and cellular glass. For finishing, thin-layer decorative plaster is used.

Plaster finishing simultaneously performs a protective and decorative function. Considering the quite reasonable cost of insulation, the facade becomes both beautiful and quite warm. The thermal insulation system of the facade is applicable to residential buildings, both existing ones and new buildings.

Such a facade makes it possible to reduce the thickness of the walls and increase them in terms of energy savings and noise insulation. The fire safety of the “wet facade” in question is also noted.

In addition, the “wet method” does not actually increase the load on the structure of the structure. When using this technology, there is an undeniable possibility of continuous thermal insulation, even despite the impressive area of ​​​​the facade.

Types of contact systems

There are two types of contact insulation system for facades - light and heavy wet method. In the latter case, the functions of the supporting structure are performed by a metal mesh, which is connected to the wall and insulation with fasteners (braces and spacers).

The easy wet method involves installing a heat-insulating layer consisting of facade slabs with glue to the outer part of the wall. After fastening, the insulation material is again covered with glue, on top of which a reinforced glass fiber mesh is placed. If necessary, the slabs are attached to the wall not only with glue, but also with dowels.

The load-bearing function falls on the heat-insulating facade slab. A reinforcing layer is distributed over the fiberglass mesh. As a rule, the total thickness of all layers is no more than 9 mm.

Advantages and disadvantages of mineral wool

These fibrous products are obtained from molten glass or silicate volcanic rocks and blast furnace slags. For heat conservation, glass wool and stone (basalt) wool are used. The main advantages of mineral insulation:

• do not absorb moisture;
• withstand significant mechanical stress;
• have biological and chemical resistance;
• withstands, without collapsing, temperatures of more than 10000C;
• perfectly absorbs noise;
• The lifespan of structures based on them is 40-50 years.

Disadvantages of the material:

• at very high temperatures it releases substances harmful to health (under normal conditions, mineral wool is not toxic);
• dust from microscopic fibers is dangerous for the respiratory tract and lungs.

When performing installation, protective equipment should be used. The cladding is carried out using the “wet” method and using the “ventilated facade” technology. This insulation is produced in the form of rolls, large slabs, and compact tiles. If you do the insulation yourself, it is better to work with tiles.

Advantages of the easy “wet” method

The advantage of facade insulation systems made using the light wet method lies in the location of the so-called “dew point” outside the wall. Thanks to this, the problem of “cold bridges” that can reduce thermal insulation disappears.

Another plus is that the living space is not reduced, because all the necessary work is carried out outside. Insulation materials are also universal materials in terms of finishing. Based on them, you can implement an aesthetically attractive architectural project of almost any complexity - for example, decorating walls with marble chips or tiles.

Flaws

This approach has some disadvantages:

• foam has very low vapor permeability characteristics - sometimes this causes discomfort due to high humidity;
• the problem of the integrity of the external finishing of the facade during shrinkage processes is not solved if the plaster layer functions for shear;
• even with very low vapor permeability, the outer layer of the finish, as well as the adhesive composition, is saturated with moisture.

Installation of a contact system has its own characteristics. One of them is careful preparation of the base.

If the structure is installed using the light wet method, the minimum ambient temperature should be at least 5°C. The low maintainability of local areas turns replacement into a labor-intensive undertaking.

Wet facade insulation technology: we understand the intricacies of this insulation technique

The walls of houses built from brick, various wall blocks, and even more so those that are a reinforced concrete structure, in most cases do not meet the requirements for regulatory thermal insulation. In a word, such houses need additional insulation in order to prevent significant heat loss through the building’s enclosing elements.

Wet facade insulation technology

There are many different approaches to thermal insulation of external walls. But if the owners prefer the exterior decoration of their house, made of decorative plaster, in a “pure” form or using facade paints, then the optimal choice is the wet facade insulation technology. This publication will discuss how complex such work is, what is required to carry it out, and how all this can be done on your own.

What is meant by a “wet façade” insulation system?

First of all, it is necessary to understand the terminology - what is the “wet facade” technology, and how does it differ from, say, conventional wall cladding with insulating materials with further decorative cladding with wall panels (siding, block house, etc.)

The technology allows both insulation and decorative finishing of the building facade

The clue lies in the name itself - all stages of work are carried out using building compounds and solutions that are diluted with water. The final stage is plastering the already insulated walls, so that the thermally insulated walls become completely indistinguishable from ordinary ones covered with decorative plaster. As a result, two important tasks are solved at once - ensuring reliable insulation of wall structures and high-quality facade design.

An approximate insulation scheme using the “wet facade” technology is shown in the figure:

Schematic diagram of insulation using “wet facade” technology

1 – insulated facade wall of the building.

2 – layer of construction adhesive mixture.

3 – insulating boards of synthetic (expanded polystyrene of one type or another) or mineral (basalt wool) origin.

4 – additional mechanical fastening of the thermal insulation layer – “fungi” dowels.

5 – protective and leveling plaster layer, reinforced with mesh (item 6).

7 – decorative plaster finishing of the facade.

This system of complete thermal insulation and facade finishing has a number of significant advantages:

• Very material-intensive installation of the frame structure is not required.
• The system turns out to be quite light. And it can be successfully used on most façade walls.
• The frameless system also predetermines the almost complete absence of “cold bridges” - the insulating layer is monolithic over the entire surface of the facade.
• In addition to insulation, facade walls also receive an excellent soundproofing barrier, which helps reduce both airborne and impact noise.
• With the correct calculation of the insulating layer, the “dew point” is completely removed from the wall structure and taken outside. The possibility of the wall getting wet and colonies of mold or mildew appearing in it is eliminated.
• The outer plaster layer is characterized by good resistance to mechanical loads and atmospheric influences.
• In principle, the technology is not complicated, and if the rules are strictly followed, any homeowner can handle it.

If desired, the external decoration of the facade can be updated

• If the work is done well, such an insulated facade will not require repairs for at least 20 years. However, if you want to update the finish, this can easily be done without compromising the integrity of the thermal insulation structure.

The disadvantages of this method of insulation include:

• Seasonality of work - it is permissible to carry it out only at positive (at least +5°C) temperatures and in stable good weather. It is undesirable to carry out work in windy weather, at too high (over +30°C) air temperatures, on the sunny side without providing protection from direct rays.
• Increased demands on both high quality materials and strict adherence to technological recommendations. Violation of the rules makes the system very vulnerable to cracking or even peeling of large fragments of insulation and finishing.

The insulation was clearly carried out in violation of the technology
. As mentioned, mineral wool or expanded polystyrene can be used as insulation. Both materials have their advantages and disadvantages, but still, for a “wet facade”, high-quality mineral wool looks preferable. With approximately equal values ​​of thermal conductivity, mineral wool has a significant advantage - vapor permeability. Excess moisture will freely find its way out of the premises through the wall structure and evaporate into the atmosphere. With expanded polystyrene it is more difficult - its vapor permeability is low, and in some types it even tends to zero. Thus, the accumulation of moisture between the wall material and the insulating layer is not excluded. This is not good in itself, but at abnormally low winter temperatures, cracking and even “shooting” of large sections of insulation along with finishing layers occur.

There are special topics of expanded polystyrene - with a perforated structure, in which this issue is resolved to a certain extent. But basalt wool has another important advantage - absolute non-flammability, which expanded polystyrene cannot boast of. But for facade walls this is a very serious issue. And in this article we will consider the best option - the “wet facade” insulation technology using mineral wool.

How to choose insulation?

Which mineral wool is suitable for a “wet facade”?

Expert opinion: Afanasyev E.V.

Chief editor of the Stroyday.ru project. Engineer.

As is already clear from the concept diagram of a “wet facade,” the insulation must, on one side, be mounted on an adhesive solution, and on the other, withstand the considerable load of the plaster layer. Thus, thermal insulation boards must meet certain requirements in terms of density and ability to withstand loads - both dent (compression) and rupture of their fiber structure (delamination).

Naturally, not every insulation classified as mineral wool is suitable for these purposes. Glass wool and slag wool are completely excluded. Only slabs made of basalt fibers are applicable, produced using a special technology - with increased rigidity and density of the material.

Leading manufacturers of insulation based on basalt fibers in their product line include the production of slabs specifically designed for thermal insulation of walls with subsequent finishing with plaster, that is, for a “wet facade”. The characteristics of several of the most popular types are shown in the table below:

There is no point in experimenting with lighter and cheaper types of basalt wool, since such a “wet facade” will probably not last long.

How to determine the required thickness of insulation?

As can be seen from the table, manufacturers offer a wide range of insulation thicknesses for “wet facades”, from 25 to 200 mm, usually in increments of 10 mm.

Plates for facade work can have different thicknesses

What thickness should I choose? This is by no means an idle question, since the created “wet facade” system must provide high-quality thermal insulation of the walls. At the same time, excessive thickness means extra costs, and in addition, excessive insulation can even be harmful from the point of view of maintaining an optimal temperature and humidity balance.

Usually, the optimal thickness of insulation is calculated by specialists. But it is quite possible to do this yourself, using the calculation algorithm presented below.

So, an insulated wall must have a total heat transfer resistance not lower than the standard value determined for a given region. This parameter is tabular, it is in reference books, it is known in local construction companies, and in addition, for convenience, you can use the diagram map located below.

Schematic map with normalized values ​​of thermal resistance of building structures

A wall is a multilayer structure, each layer of which has its own thermophysical characteristics. If the thickness and material of each layer, existing or planned (the wall itself, interior and exterior decoration, etc.) is known, then it is easy to calculate their total resistance, compare with the standard value in order to obtain the difference that needs to be “covered” by additional thermal insulation.

We will not bore the reader with formulas, but will immediately suggest using a calculation calculator that will quickly and with minimal error calculate the required thickness of insulation with basalt wool intended for facade work.

Calculator for calculating the thickness of insulation of the “wet facade” system

The calculation is carried out in the following sequence:

• Using the diagram map for your region, determine the normalized value of heat transfer resistance for walls (purple numbers).
• Check the material of the wall itself and its thickness.
• Decide on the thickness and material of the interior walls.

The thickness of the external plaster finishing of the walls is already taken into account in the calculator and will not need to be added.

• Enter the requested values ​​and get the result. It can be rounded up to the standard thickness of manufactured insulation boards.

If suddenly a negative value is obtained, insulation of the walls is not required.

Go to calculations

What other materials and components will be required?

To decide on the materials, it is necessary to once again consider in detail the scheme of the future “wet facade”.

Materials and components required for insulation using “wet facade” technology

1 — starting (basement) profile. Its width must exactly match the thickness of the insulation. The number of profiles corresponds to the perimeter of the insulated walls.

2 – connecting elements for the base profile. They ensure precise joining of profiles in one plane and set the required temperature gap between them. Quantity: one for each joint, or two for insulation thickness of 100 or more.

3 – profile fastening. Expansion dowel nails must have a length of at least:

- for concrete walls or those lined with solid brick - 40 mm;

— for walls made of hollow bricks – 60 mm;

— for gas silicate blocks or other low-strength materials – 100 mm.

It is not difficult to calculate the number of fastening points: for insulation with a thickness of 80 mm and above, increments of 300 mm; for thicknesses less than 80 mm, it can be installed in increments of 500 mm.

A plastic spacer washer is provided at each attachment point for precise alignment of the profile.

4 – primer for preparing the wall for gluing slabs.

— For brick, plaster or gas silicate walls, deep penetration soil will be the best choice. Average consumption – 300 ml/m².

— For concrete walls, soil of the “concrete contact” type is purchased. Average consumption – 400 ml/m².

5 – adhesive composition for installation of insulation boards. It should be designed specifically for such tasks - for attaching a thermal insulation layer.

Various types of adhesives for insulation work

There are many of its varieties - usually mineral wool manufacturers give their recommendations on the most adapted compositions or even offer their own proprietary mixtures.

The average glue consumption at this stage of work is approximately 6 kg/m².

6 – insulation boards with calculated thickness. Average consumption, taking into account cutting and possible waste, is 1.05 m² per 1 m² of wall.

7 – “fungi” dowels for additional mechanical fastening of the insulation. The total length of the dowel must correspond to the thickness of the insulation plus the length of the spacer - depending on the wall material (see above).

Dowel-mushroom with metal spacer nail and thermal head

It is preferable to use dowels with a plastic expansion nail or with a core equipped with a special thermal insulation head - so that “cold bridges” are not created.

Average consumption – 6 pcs/m².

8 – basic protective reinforced plaster layer over insulating boards. A special plaster composition or the same adhesive composition that was used for installing the slabs is used.

The thickness of the layer is 4 mm - for further application of decorative plaster, or 5 mm - if simply painting with facade paint is intended. Based on this, the consumption also varies - from 4 to 5 kg/m².

9 – reinforcing mesh made of alkali-resistant fiberglass. Usually sold in rolls 1000 mm wide. Average consumption is 1.1 linear meters per 1 m² of wall.

9a - not shown in the diagram, but during the work you will definitely need reinforcing corners with mesh strips - for plastering corners on knocking walls and on window and door slopes.

PVC corner with strips of reinforcing mesh

Consumption - based on the actual total length of all corners.

10 – water-dispersion primer – for preparing the plastered surface for finishing work. Average consumption - 150÷200 ml/m².

11 – decorative plaster of the selected class. Consumption depends on the type of plaster and its specific qualities.

12 – facade paint.

Points 11 and 12 already relate, rather, to finishing work, and will not be considered within the framework of this publication.

Some manufacturers offer complex “wet facade” systems that include all the necessary materials - from insulation to finishing decorative plaster of facade paint, and a full range of all necessary components. This is generally the optimal solution, since all components of the system are maximally adapted to each other.

The calculator below will help you quickly calculate the required amount of basic materials for a wall of a certain area.

The area of ​​the wall is easy to calculate. For a rectangle, this is the product of length and height. If the wall has a complex configuration, other geometric relationships are used.

Need help finding the areas of complex shapes?

A special publication on our portal dedicated to calculating areas will help the reader quickly and accurately make the necessary calculations.

Calculator for calculating the amount of required materials

Go to calculations

Carrying out work using “wet facade” technology

In order for the insulation of walls using the “wet facade” principle to be high-quality and durable, it must be carried out strictly in stages, with strict adherence to all technological recommendations. Each step is important, and ignoring one or another operation will inevitably lead to marriage.

Preparing the wall surface for insulation work

When insulating a facade using this technology, thermal insulation will be effective only if maximum contact is ensured between the wall and the insulating layer. This, in turn, means that careful surface preparation is essential.

• The slabs will be mounted with glue, but it is designed for “clean” wall surfaces, without paint residues. If the façade was previously painted, you will have to clean it down to the base or a stable plaster layer.

Walls for such insulation require high-quality cleaning.
Cleaning can be carried out mechanically, using heat using a construction hair dryer or using special flushing compounds - depending on the specific initial conditions. But the goal is the same - the base must be clean, without paint stains, oiled or bitumen-impregnated areas.

• You can leave old plaster only if its condition does not cause any concern. This must be verified by carrying out a thorough tapping test - unstable areas must be removed without any pity.
• It is prohibited to carry out work on a wall that has even the slightest signs of mold, moss, fungus, etc. All this must be cleaned off, and then the entire wall is treated with a special “treating” composition - in accordance with the instructions attached to it. You can proceed to further stages only after the bactericidal treatment has completely dried.

The wall clearly needs “treatment” with antiseptic compounds.
However, even if there are no obvious signs of damage to the wall by microflora, it will not hurt to carry out such “health” measures in any case.

• The wall should be fairly level. All potholes, remote areas, cracks, crevices must be repaired - cut, primed and tightly filled with repair mortar, leveling these “patches” to the general level of the wall. Existing protrusions are knocked down - in the same way, to the general level.
• They inspect the plane of the wall - vertically and horizontally. If there are significant deviations (more than 20 mm), then you should not hope to level them later, with a layer of insulation and subsequent decorative plaster - nothing good will come of this. Leveling will have to be done now, using conventional cement-sand plaster, optimal for the specific wall material. True, the work will be delayed - it will be possible to proceed to the installation of insulating boards no earlier than in 3 ÷ 4 weeks.
• All metal elements necessary for the installation of antennas, drains, air conditioning systems, lighting, etc. must be pre-installed on the walls. These brackets must be immediately coated with anti-corrosion primers.

All metal parts of the facade must be treated with anti-corrosion primer

• When the repair or plaster layer on the wall is completely dry, the entire surface is treated with a primer. The type of primer and its consumption have already been discussed above. Application is carried out with a roller or, in hard-to-reach places, with a brush. It is important not to miss the slightest section. If excessive absorption of the composition is detected in any area, then do not skimp on the primer - the area should be treated twice.

Once the soil has dried, the first stage can be considered complete.

Installation of the base profile

The base profile on which the first row of insulation boards will be installed must be mounted strictly along the horizontal “zero” line, which is marked using a laser or water level. An important condition for high-quality insulation of the first floor is that this line must be at least 300 mm below the floor level in the rooms so that there is no “cold bridge” left.

A correctly set profile solves two main problems. It ensures even laying of insulation boards and becomes protection from below, in the only place where mineral wool will not be covered by a plaster layer.

Scheme of fastening the base profile

The types of fasteners and the step of their installation have already been discussed above. Plastic spacer washers (item 1) are used to compensate for slight curvature of the walls, if necessary, so that the profile is pressed tightly to the surface but at the same time does not deform.

Profiles are never installed overlapping - only end-to-end, leaving an interval of 2-3 mm. This is ensured by connecting elements (item 2) - one or two for each joint.

At the outer or inner corners of the wall, the profiles are also joined, leaving a gap. To do this, they are cut at an angle of 45°, and a connecting element is inserted at the joint. Another option is to cut a 90° angle inside the profile, leaving only the outer limiting edge intact. Then the profile is bent at a right angle, and a connecting element is also inserted at the joint. These measures will allow you to maintain a perfectly even horizontal profile line along the entire perimeter of the building.

In the event that insulation with a thickness of over 80 mm will be installed, you should consider the issue of temporary stops under the starting profile so that it does not sag at the initial stage of gluing the slabs. After the insulation is installed, these stops are simply removed.

Typically, the base profile is installed immediately along the entire perimeter of the insulated walls. Then you can move on to the next stage - gluing the plates.

Installation of insulation boards

To install the slabs, the adhesive composition is prepared in strict accordance with the instructions attached to it.

The dry mixture is gradually added to the required amount of water and at low speeds of the mixer it is gradually brought to the desired consistency, without lumps. This usually takes at least 5 minutes. Then a pause is made - for 6 ÷ 8 minutes, and after that the composition is mixed again for 5 minutes.

The adhesive composition is diluted in strict accordance with the instructions attached to it.

You should not make too much of the mixture at once - its “life” is limited, and adding water when signs of setting appear will not do anything. If there was a short break during work, about 10÷15 minutes, the mixture should be mixed again with a mixer.

Glue can be applied to slabs in several ways.

• This is usually done around the perimeter, with a distance from the edge of 20-30 mm, strips 100 mm thick, and also in the center - three slides with a diameter of about 200 mm. The height of the applied layer is about 20 mm, but it can vary slightly (no more than +10 mm) depending on the degree of evenness of the base.

Recommended scheme for applying adhesive to boards

• If the wall to be insulated has excellent evenness, then ruts can be applied over the entire surface using a notched trowel with a comb height of 12 mm.

In both cases, it is recommended to apply the glue in two stages:

- first, a small amount of glue is rubbed with force into the surface of the slab in the right place.

— then the required amount of composition is applied.

In those places where the slab will extend around a corner or over a slope, glue is not applied.

The glue-coated slab is installed in its intended place and pressed tightly against the wall surface. Light movements up and down and to the sides while pressing against the surface ensure uniform distribution of the glue. All excess that appears at the edges is immediately removed with a spatula.

When installing the next slab, they achieve the tightest possible connection, without the slightest gaps. If gaps cannot be avoided, then they are subsequently tightly filled with cut out wedges of mineral wool. Filling the voids between the blocks with glue is strictly prohibited!

Laying is usually done from one of the corners, in a row. At the same time, be sure to follow several important rules.

Basic principles of correct placement of insulation boards

• The first row should rest against the starting profile, exactly along the limiting edge.
• The slabs are laid “in a bandage”, with the vertical joints offset by at least 200 mm (item 1).
• At the corners, the “gear lock” principle is observed (item 2).
• A slab fragment adjacent to a corner or slope cannot be less than 200 mm wide (item 3).
• Usually, a connection is immediately provided for the insulation of the wall and slopes, which is also done with mineral wool slabs, but of lesser thickness (item 4).

The junction of slabs to slopes requires special attention.

This arrangement of the slabs relative to the edges of the slopes will certainly lead to cracks.

No matter how the vertical and horizontal seams go when laying the slabs, they should not coincide with the continuation lines of the slopes, otherwise the plaster finish will inevitably crack in this place. If such a situation occurs during installation, then inserts are made at the corners of the slopes, the thickness of which both vertically and horizontally must be at least 200 mm. These inserts can then be cut to fit the window opening.

This issue is solved by inserts at the corners of the opening.

The cutting of the slabs is carried out using a hacksaw with a fine tooth or a special knife.

Special knife for high-quality cutting of mineral wool boards

During installation, constant monitoring of the evenness of the resulting plane is carried out - until the adhesive mass has hardened. There is still an opportunity to make certain adjustments. For control, use a long rule and a building level.

The adhesive mixture must be given about three days to dry completely, and then additional mechanical fastening of the insulation water is carried out using dowels-“fungi”. Typically, 5 fasteners are used for each slab - in the corners and in the center. Often, in order to save money, dowels are installed in such a way that their head simultaneously holds adjacent slabs.

Recommended arrangement of dowels-"fungi"

A drilling depth limiter is installed on the hammer drill to ensure the required length of immersion of the spacer part of the dowel into the wall + 15 mm.

A hole is carefully drilled directly through the insulation, avoiding beating. A “fungus” is inserted into it and fixed with a spacer core. The hat should be slightly wrinkled, 0.5 ÷ 1 mm, into the mineral wool layer. The central hole of the dowel should be covered with a thermal cap. If it is not there, you can insulate it with polyurethane foam.

The installation of insulation boards is completed by checking the surface for the absence of cracks or places of loose fit. All identified defects are eliminated by densely inserting mineral wool wedges.

Find out which insulation is not chewed by mice from a new article on our portal.

Application of a base layer of reinforced plaster

The installed insulation requires covering with a protective reinforced plaster layer. as already mentioned, the same adhesive mixture can be used as the base material, but it is also possible to use a different solution recommended by the slab manufacturer and included in the overall insulation system. For example, in the ROCKWOOL ROCKFASAD system, the use of a special ROCKmortar plaster mixture is recommended. But the application technology does not change.

ROCKmortar plaster mixture

• The composition is diluted in the required quantity (ensuring its production within 1÷1.5 hours) in accordance with the instructions.
• Work begins with the most difficult areas - corners and slopes.
• An adhesive composition approximately 200 mm wide and 2 mm thick is applied to the sides adjacent to the corner. It is advisable to use a notched trowel with a ridge height of 5 mm - this will make it easier to stick the reinforcing layer.
• A corner with mesh stripes is installed, strictly along the line of the corner.

Corner reinforcement using a special profile

• Using a regular flat spatula, the mesh is pressed and sunk into the layer of solution. It is important not to leave “dry” areas, but at the same time, the mesh should remain in the thickness of the solution, and not lie close to the insulation.

On slopes the task is a little more complicated - here it is necessary to ensure a connection to the window or door structure. I usually do this - a special connection profile (U-shaped) is attached to the window or door block. The corner mesh is inserted into it (item 1), and then the entire slope is plastered with a base layer, so that the reinforcement remains inside it. The total layer of plaster on slopes should usually be thicker than on walls - about 6 - 7 mm.

Approximate scheme of slope reinforcement

Additional reinforcement of the tops of the corners of window and door openings is required. To do this, rectangular “kerchiefs” are cut out, which are applied as shown in the figure (item 2) and sunk into the plaster mortar.

Now you can move on to the surface of the walls. It is covered with plaster according to the same principle.

— The mesh is cut into strips (you shouldn’t get carried away with too long ones - it will be inconvenient).

— The glue is applied and distributed over the wall in a vertical strip of 1100 - 1200 mm, using a notched trowel.

— The first mesh strip from the corner is glued to the mortar so that there is an overlap of approximately 100 mm with the already completed reinforcement.

— Using the force of a spatula, the mesh is recessed into the applied (approximately 2 mm) layer of solution.

Embedding reinforcing mesh into a layer of plaster

— The next strips are also laid with an overlap of 100 mm both vertically and horizontally.

— From below, the excess mesh is trimmed to the level of the base profile.

Trimming excess reinforcing mesh

It is important to ensure uniform distribution of the solution over the entire surface of the wall and complete “immersion” of the mesh. That is why the use of a notched trowel seems to be the most convenient method.

The glue should set slightly - and it will be possible to carry out preliminary grouting, so as to achieve a uniform layer of approximately 2 mm. Then another layer of mortar is applied - also 2 mm, or 3 mm if it is not intended to use decorative plaster, but to limit it to façade paint.

When grouting the second layer, the task is to level the wall surface as much as possible in order to avoid even small defects, which may well appear through the decorative finish.

Grouting the base plaster layer

After the plaster leveled surface has completely dried (and this will take at least 72 hours), it is covered with a layer of water-dispersion primer, which will ensure reliable adhesion to the decorative coating.

If work is carried out during a hot period, then while the plaster layer is drying, it must be protected from direct sunlight - uneven evaporation of moisture can lead to the appearance of a network of small cracks.

The finished surface becomes a “blank slate” for any type of facade paint or plaster. But this is already a topic for a separate consideration, dedicated specifically to finishing work.

The work is completed by applying decorative plaster or facade paint

And at the end of the publication - a video tutorial on how to insulate walls using the “wet facade” technology using TechnoNIKOL materials.

Video: insulation using “wet facade” technology

Mounted systems

Wall mounted facade insulation systems are considered more modern and have many advantages over the contact method:

• their use makes it possible to reduce energy costs for heating by more than 1.5 times;
• no need to prepare the base before installation;
• can be installed at any time of the year;
• service life is about 30 years.

Insulation boards in this case are attached to the surface mechanically - dowels or load-bearing elements are used. At a distance of 2-5 cm from the outer part of the heat insulator, elements of external finishing are placed, which perform two functions at once: the first is decorative, the second is protective.

The surface layer of the system is made of various materials - from stone and metal to ceramics and wood. You can decorate the facade with glass, which has become very popular in the decoration of office buildings. In this case, the insulation board is covered with white or black glass fiber canvas. An important advantage of ventilated facades is the removal of moisture accumulated in rooms without forced ventilation.

For the manufacture of curtain-type facades, sandwich panels are often used - structures consisting of a heat-insulating core and 2 steel sheets. They are suitable for finishing both new and reconstructed buildings. Products from different manufacturers differ in color, size and other features. However, high-quality sandwich panels are united by high reliability, durability and wide functionality.

Advantages of complex systems for facades

When using facade insulation systems, the color scheme of the facade can be changed at any time. Taking into account the thermal insulation system of the facade at the design stage of the building saves on expensive building materials for walls. The difference in price for a medium-sized building with and without insulation is on average about 150 thousand rubles, but if you take into account the heat savings, such finishing will pay for itself by reducing heating bills within 5-7 years.

If the structure is built from foam concrete, based on the insulation system, it is possible to use a block whose thickness is 10-15 cm thinner. When erecting a building made of brick, the fence structures are mounted in one brick and are 64 cm.

Standards

Everything that happens in the atmosphere, including the phenomena of natural cycles and the consequences of technogenic human activity, causes increasingly sharp temperature changes, which is strongly reflected on the surfaces of structures and buildings. Without additional protection, facades gradually deteriorate under the aggressive influence of the environment.

As a result of such exposure, the building cannot effectively conserve heat during the cold season. Today in construction it is believed that, regardless of what material the walls were built from, it is necessary to carry out auxiliary insulation with a material at least 50 mm thick.

According to Russian standards, for a brick-silicate wall built with 1.5 bricks, it is necessary to use insulation with a thickness of 100-120 mm. Such a house will fully comply with current energy efficiency requirements. Naturally, the market value of such a house with subsequent insulation using facade insulation technology increases almost 2 times, but an insulated facade will subsequently bring serious savings on repairs and heating.

Criteria for choosing insulation

When selecting facade insulation, it is necessary to take into account the type of wall material, thickness, architectural features and dimensions. Climate and weather conditions are also taken into account. The thickness of the insulation layer is determined by the building density of the area - a building that stands alone requires a larger layer of insulation than a house located in the central part of a densely populated village.

The thermal insulation layer in facade systems is made from extruded or ordinary polystyrene foam, as well as from laminated or ordinary mineral wool. Both types of material are supplied in slabs. Mineral wool is made from glass, soda, limestone and sand. Its structure is represented by glassy thin fibers. Positively distinguished by high vapor permeability.

Expanded polystyrene is a polymer that has the following positive qualities: it does not enter into chemical reactions with other substances, is resistant to moisture and is not susceptible to rotting and fungus. It is recommended for use for insulating plinth slabs. According to statistics from the last 3 years, consumers prefer systems made of polystyrene foam as the cheapest material.

What issues need to be resolved before installing insulation?

To avoid problems when working with insulation and finishing, you need to immediately take care of purchasing all components of the system, as well as tools and consumables.

Choice of insulation

The most careful attention is paid to the type of thermal insulation material, which should retain heat well and not trap moisture inside. Also, the insulation must withstand the load of the plaster layer, have optimal density, and resist dents and tears.

Most often, expanded polystyrene with a density of 16-18 kg/m³ is used for the installation of a wet facade. This insulation is moisture-resistant, durable, and easy to use.

Expanded polystyrene PPS-35 for facade insulation

However, when cladding houses made of porous materials, it is necessary to take into account the risk of moisture accumulation and be sure to provide forced ventilation. Special sheets for facades of type PSB-S 25F, which have the necessary properties, are best suited.

If you decide to install insulation boards on the walls of public buildings, it is important to strictly follow fire safety recommendations. For this purpose, the coating is cut with non-flammable basalt wool bridges, which reduces the risk of fire spreading along the facade. In private housing construction, such insulation is usually treated with fire retardants - special impregnations.

Special mineral wool MVP slabs with a density of 130-150 kg/m³ are suitable for working with wet facade systems. They are used with only one caveat: the top layer of cladding must have high vapor permeability.

Mineral wool slabs
For this reason, the following are not suitable for finishing according to MVP:

• acrylic-based paints and plasters;
• artificial and natural stone;
• clinker tiles.

Occasionally, wood concrete is used as insulation; glass wool and slag wool are not used at all.

Materials and components

To work you will need a list of the following accessories:

• a starting profile with a width corresponding to this indicator for the insulation (the quantity is selected along the perimeter of the walls), with connecting elements for each joint;
• fastening dowels of a certain length (for concrete and brick - 4 cm, for hollow brick - 6 cm, for gas silicates and other materials - 10 cm);
• adhesive composition for attaching insulation;
• deep penetration primer or concrete contact, as well as water-dispersion primer for plaster;
• mushroom dowels for insulation with a plastic spacer mushroom;
• insulation boards (when calculating the quantity, possible waste and damage during cutting are taken into account);
• facade alkali-resistant fiberglass mesh and reinforcing corners with mesh strips;
• decorative plaster and facade paint;
• anti-corrosion composition for metal.

Materials for constructing a wet façade

Tools for work

From the tools, as well as additional devices, you may need:

• drill (screwdriver);
• hammer drill with attachment for dowels;
• mixer attachment for drill;
• knife (cutter) for profile;
• spatulas 100 and 350 mm wide for plaster;
• serrated trowel for glue;
• level;
• hammer;
• square;
• roulette;
• a hacksaw or knife for cutting insulation;
• brushes or rollers for primer and paint;
• containers for plaster and glue;
• ironer;
• grater with sandpaper;
• trowel for decorative plaster;
• rags;
• nylon cord and plumb line;
• masking tape.

Determining the thickness of insulation

There are special calculators on the Internet that allow you to correctly calculate the thickness of the insulation. To get the figure you need to know:

• thickness of walls, interior decoration;
• standard heat transfer resistance (available in construction reference books, depends on the region).

Afterwards, insulation is selected that is close to the obtained thickness value. Usually on sale you can find material of 25-200 mm in increments of 10 mm.

Environmental conditions

Work on installing insulation using wet facade technology is carried out at an ambient temperature within +5...+25 degrees. If the regime is violated, you can get a cracked, crumbling coating.

Important! It is best to do a wet façade in late spring or early summer.

Installation

You can install a facade insulation system with your own hands, however, specialists with experience will cope with this task faster. Insulation work involves several stages, after each of which you need to check the absolute evenness of the surface, cleanliness and smoothness.

It is very important that there are no depressions or cracks on the surface of the walls - otherwise the finishing layer will not be continuous, and the thermal insulation will become ineffective.

Differences in materials

Weather requirements are the same for both mineral wool and expanded polystyrene. The technology in both cases is virtually identical, and only the fastening method differs. Glue is applied to polystyrene foam boards over the entire surface, around the perimeter, or in “patches”.

In the case when polymer insulation is fixed to plastered walls, in addition to glue, dowels are used, at a rate of at least 4 per 1 m2. For mineral wool slabs, mechanical fastening is mandatory. Dowels with a tip made of galvanized steel are used.

The next point that requires special attention is the hydrophobicity of mineral wool. On this basis, before applying an adhesive solution to the surface of the slab, it is first puttied with an identical solution. Next, a layer of reinforcement must be applied to the thermal insulation slabs; after setting, it is primed with plaster mixture.

The plaster backing compound of the wall protects the building for 6 months if work is suddenly suspended. The procedure for applying the plaster itself summarizes. When directly applying and drying the plaster, temperature indicators should vary in the range from +5С to +25С.

Features of facade insulation with mineral wool

The popularity of polystyrene is due to its low purchase price, easy workability and the possibility of very quick gluing. However, insulating the exterior of the house façade with mineral wool under plaster comes to the fore. The material is used for finishing not only commercial, but also high-rise and public buildings. According to the updated standard, wool is required for use in the construction of structures more than 20 meters high.

In addition, insulating the facade outside the house with mineral wool provides excellent sound insulation. Therefore, the material can be used to insulate houses on busy streets. In combination with special plasterboard boards, mineral wool sheets can be used in the construction of partitions when good acoustics are required.

Advantages of insulating the façade of an apartment building from the outside with mineral wool:

1. The material, due to its low diffusion resistance, has excellent vapor permeability and prevents the formation of mold.
2. When used correctly, mineral wool has a virtually unlimited service life, making it an excellent choice for building insulation.
3. High fire resistance. If it is a high-rise building, wool insulation must be used starting from the seventh floor. On the lower floors, strips of mineral wool are inserted next to the windows and also under the roof to prevent the spread of fire in the event of a fire.

Insulating the exterior of a house with mineral wool provides excellent sound insulation

The material is impregnated with chemicals, so it does not absorb moisture, as a result of which it is not afraid of corrosion or rotting. And thanks to its simple shape and flexibility, cotton wool can fill even the smallest cracks and bends. Disadvantages of facade insulation with cotton wool:

• heavy weight, causing difficulties during installation;
• the price of insulation will be about a third higher than when using polystyrene, the cost of insulating walls outside per 1 sq. m starts from 1900 rub.

Types of material used for wall insulation

There are two main types of materials used in the production of wool - glass and mineral. Glass wool is made by cooking cellulose with the addition of other ingredients. Mineral wool is obtained by melting rocks, it is also called stone or basalt. Glass wool is non-flammable, vapor permeable and flexible, suitable for all non-stressed and non-slip structures, such as inclined walls, various cavities and gaps, even ceilings.

Materials such as glass and mineral are used in the production of cotton wool.

It is a little more difficult to use stone wool for facade insulation due to the fact that it is heavier than glass wool and less elastic, but the material provides ideal thermal insulation of the outer cladding of the building. Any façade wool should always be glued to a dry and solid base.

When insulating a facade with mineral wool, the following types of material are used:

1. Transverse fiber orientation. Suitable for façade systems where heavier tiles will be used. The material has high tensile strength.
2. Longitudinal fiber orientation. Designed for application to external walls and contact insulation systems.

Due to its good characteristics and low flammability, cotton wool can be used in conjunction with any materials. It is popular to insulate the exterior of the house with mineral wool under the siding; in this case, you will be able to get both a thermally efficient and beautiful house.

Any type of facade wool must always be glued to a solid and dry base