Please tell me when laying bathroom walls from aerated blocks, do they need to be treated with something? As I understand it, gas blocks absorb moisture well; can they even be placed in the bathroom? Thanks in advance for your answer!
Answer: Yes, you are right, aerated concrete blocks have high vapor permeability, and in the bathroom you know it’s constantly standing high humidity air. Having such high ability absorb moisture, aerated concrete blocks can be used for the construction of walls and partitions in bathrooms only after protective waterproofing measures have been taken after the construction of the walls.
The first thing you have to do is prime the entire surface of the bathroom walls with a deeply penetrating primer, for example ST-17 from Cerezit. The soil will provide you with the preparation of aerated block walls for applying a leveling layer of putty, for example ST-29.
Puttying the walls must be done very carefully, since a layer of putty will protect your aerated concrete from moisture. After the putty layer has dried, it is necessary to treat the floor and wall surfaces to a height of 200 mm from the floor level with waterproofing cement based Ceresit CR 65. Well, then tile moisture-resistant adhesive CM-17 from the same company and calmly lay ceramic tiles on the walls of your bathroom. After completing such work, you will reliably protect bathroom walls made of aerated blocks from moisture.
As you know, any room begins, in the dry language of construction terms, with the construction of enclosing structures. In order to do right choice building materials For bathroom walls, it is necessary to take into account many sometimes incompatible factors, the characteristics of each material, and make the most of their positive qualities, leveling out the shortcomings as much as possible. Let's look at what types they have different kinds structures, be it a concrete or brick wall in the bathroom.
The construction of bathroom walls faces numerous technical and legislative restrictions. Incorrect selection of material for building walls can lead not only to legal consequences for the owners of the premises, but also to physical destruction of existing buildings. Compliance with regulatory documentation and technology requirements construction work guarantees and high quality construction and its safe operation.
Properties of building materials used in the construction of bathroom walls
Of all the variety of properties, building materials for bathrooms must meet a fairly small list of characteristics that make it possible to obtain a balanced building structure without significant labor costs and waste of materials:
- Specific gravity. One of the key parameters that directly shows how much it will weigh building construction, occupying a certain volume. Since the bathroom walls are built on slabs interfloor ceiling, then the excess permissible load, and it is 800 kg/m2 for new floors, can cause the collapse of the structure;
- Load bearing capacity. Directly depends on the strength of the material and its ability to withstand static and dynamic loads without destruction;
- Fire resistance. Ability to withstand exposure to open flame and high temperature for a specified period of time. Has a direct impact on the safety of the premises. Failure to comply with fire resistance requirements may serve as grounds for refusal to accept the premises by the interdepartmental commission;
- Moisture resistance. The ability of a material to resist the effects of water vapor and withstand direct contact with water without causing irreversible changes structure and strength. Plays a big role in creating and maintaining the microclimate of the bathroom, the resistance of walls to the spread of fungal microorganisms;
- Thermal conductivity. The property of materials to prevent the transfer of heat outside the bathroom. Without taking into account the thermal conductivity of the material, it is impossible to create the desired microclimate;
- Linear thermal expansion. One of the main parameters that you need to pay attention to when using plastic products. All plastics change their properties significantly when temperature fluctuates. linear dimensions, which can lead to surface deformation.
Analysis of materials for bathroom walls
Ceramic brick
Until recently brickwork was the only way to lay out the walls of the bathroom and toilet inside the living space. Availability of material, low complexity of work and high strength of structures. Bathroom with brick wall has excellent performance indicators, is easy to install indoors and can have complex geometric shape. The brickwork of the bathroom walls is made of solid clay or hollow brick.
Depending on the size of the room, you can use half-brick or one-quarter brick masonry, but the second option requires more highly qualified mason and increased by one third the time required to build the wall. Brick wall, made of facing hollow bricks can serve decorative element interior without additional finishing.
Important! When using bricks, it must be remembered that the masonry is carried out according to a scheme called ligation of seams, when the load of the upper row is distributed over two underlying bricks, this ensures high strength of the masonry. If a bathtub with a brick wall is to be plastered, then the masonry is done in a waste area for better adhesion of the plaster mortar.
Ceramic bricks, intended for laying walls and partitions, have the following advantages:
- High compressive strength, determined by the brand of brick, where the number shows how much load in kilograms 1 square cm of surface can withstand;
- Good surface wear resistance;
- Low water absorption at 14% for ordinary bricks and no more than 3% for clinker bricks;
- Good sound insulation properties that meet the requirements of regulatory documentation;
- Environmentally friendly material made from natural clay without chemical additives.
Some inherent disadvantages of ceramic ordinary brick reduce the attractiveness of the material for building walls indoors:
- High dead weight. Square meter masonry weighs about 220 kg;
- High cost of high-quality brickwork;
Foam concrete
A modern building material created on the basis of cement-sand mortar with the addition of foaming additives, which determine the porous structure of the material after hardening. The properties of foam concrete are ideally suited for the construction of non-load-bearing partitions inside finished building structures.
The walls in the bathroom made of foam blocks are small in thickness and have their own weight. One standard size block weighing no more than 18 kg replaces about 20 ceramic bricks with a total weight of about 80 kg. A more than 4-fold reduction in the load on the floors allows you to build plumbing cabins anywhere in the room.
The material is very environmentally friendly and does not contain harmful impurities. Foam blocks for the bathroom do not absorb moisture, creating a favorable indoor microclimate. The foam block made from natural ingredients does not burn, and its heat and sound insulating properties make it possible to reduce the thickness of the wall being built to a size sufficient to maintain the strength characteristics of the structure.
Note: The material can be easily cut and drilled with tools designed for wood, and does not require a thick layer of plaster for final finishing.
Foam blocks are made by casting in special molds or cutting from a finished monolith, which does not affect the quality of the material. Foam blocks for bathroom partitions have the following advantages:
- Low dead weight, guaranteeing the impossibility of overloading the floors;
- Low shrinkage under load;
- High sound and thermal insulation properties;
- Easy installation and processing, with the ability to cut out shaped structures;
- Low price;
- Low water absorption. Foam block can long time float in water without compromising the properties of the material;
In front of everyone positive qualities foam blocks also have some disadvantages that must be taken into account during construction:
- Difficulty in securing heavy objects;
- Long-term gain of structural strength and some shrinkage of the material;
- The need to apply a plaster layer;
- The use of a synthetic foaming agent instead of a natural one reduces the strength of the block.
Aerated concrete
One of the varieties of cellular concrete, which is used as a material for bathroom walls, is aerated concrete. The cement-based material is chemically foamed using aluminum powder and hardens at high temperatures in a special autoclave. Hardening of aerated concrete blocks occurs in special installations at high temperatures, which increases specifications material. After cooling, aerated concrete continues to increase its strength over time to the value established by the characteristics.
Aerated concrete blocks in the bathroom must be insulated from moisture with inside, since the porous structure can absorb a large number of moisture. Aerated concrete has the highest strength characteristics among cellular concrete, and its surface holds better Decoration Materials. Bathroom walls made of aerated concrete are almost as strong as brick walls, but are several times lighter, and laying the blocks using a thin layer of special glue reduces the cost of work.
Important! One of the varieties of aerated concrete is gas silicate, produced using a similar technology from a silicate mixture and a foaming agent. Apply gas silicate blocks in the bathroom it is undesirable due to their high absorbency and low thermal resistance.
At standard sizes block 600x200x100mm they have the following advantages:
- Better heat and sound insulation than foam concrete;
- Excellent fire resistance. The material can be on fire for several hours;
- Simplicity machining without the use of special tools;
- Less amount of cement used in production;
The increased porosity of the material entails some easily removable disadvantages:
- increased hygroscopicity;
- the most high price among cellular concretes.
cinder block
When choosing a material for the walls in the bathroom, you can successfully use a universal hollow building stone obtained by vibration pressing. cement mortar with a filler of metallurgical granulated slag. Cinder block is cheap to manufacture and can even be made independently without the use of expensive equipment. Bathroom blocks are made hollow with a total thickness of 100 mm, which improves technical and operational characteristics and reduces material consumption.
The main advantages of cinder block:
- High mechanical strength;
- Resistance to water and high temperature;
- Relatively light weight;
- Low cost and the possibility of self-production;
- Possibility of using any filler capable of being held together with cement binders.
Among the disadvantages it is necessary to note:
- Increased surface roughness, requiring plastering work;
- Application for processing special cutting tools.
Important! When choosing cinder blocks, you need to pay attention to the components from which they are made. Not all are suitable for use in residential premises, because... may contain hazardous impurities and components for human health. Such blocks can only be used for the construction of households. buildings
Sheet materials based on cement binders
Construction materials for the bathroom based on cement binders include a group sheet materials in which various fillers are used. This and cement bonded particle board, in which waste from woodworking and flat asbestos cement sheets of varying thickness, better known as “slate”.
The materials have sufficient strength, and are mounted on a wooden or metal carcass using standard fasteners. It is advisable to use slate walls in the bathroom as a base for finishing materials when sealing technological channels in order to avoid unreasonable reduction internal space. The advantages of slate as a material for building walls lie in its excellent water resistance, and all other qualities can be attributed rather to disadvantages:
- Increased fragility;
- Use of asbestos as a filler, which releases harmful substances when heated;
- Quite heavy weight;
Cement particle board is much better suited for the construction of walls in terms of its performance qualities:
- High strength in the longitudinal direction:
- Good sound insulation properties;
- Increased water resistance and resistance to rotting;
- Ability to resist high temperatures and prevent the spread of fire;
- Excellent vapor permeability.
Among the disadvantages of DSP, one can note the increased weight and some complexity of installation compared to plasterboard.
Tongue-and-groove gypsum board
You can significantly speed up the installation of a plumbing cabin if you use tongue-and-groove blocks for the bathroom and toilet. But faster doesn't mean better. Tongue-and-groove slabs are high-tech gypsum products cast in metal form and equipped with special locks to facilitate joining the plates to each other. The rather large dimensions of the slab, 500x667mm, allow the construction of even plaster walls with perfectly fitted joints, requiring no further pre-treatment.
Regular tongue-and-groove slab in the bathroom allows you to immediately stick facing tiles or paint with preliminary finishing putty. The thickness of the slab is 80 mm and is considered sufficient to ensure the strength of the enclosing structures of the plumbing cabin and provide the required level of thermal insulation.
For your information: Hollow PGP, in which air channels are provided to lighten the weight, has an insufficient level of sound insulation. Acoustic vibrations arising in the channels can be amplified to such an extent that the tongue-and-groove wall in the bathroom will serve as a kind of sound system, relaying sounds occurring behind adjacent walls.
The use of gypsum, even with water-repellent additives, does not allow the PGP to be considered completely waterproof, which requires additional waterproofing. Despite all the attractiveness of the tongue-and-groove slab, only a few advantages can be identified when constructing walls in the bathroom:
- High speed of installation with prepared floor surface;
- Low cost of material and the opportunity to save on subsequent finishing operations.
But this material has many more disadvantages:
- Low strength, especially hollow slabs when securing heavy equipment causes serious problems;
- Insufficient moisture resistance;
- Poor sound insulation;
- Heavy weight, which makes it difficult to install the upper part of the wall;
- A large amount of harmful gypsum dust when cutting the material.
If the technology is strictly followed and the adhesive materials specified in the instructions are used, you can use GGP for the construction of bathroom walls, but it is better to do tongue-and-groove partitions in bathrooms that separate part of the room for the toilet.
Sheet gypsum materials
About application plasterboard systems I didn’t write unless I was very lazy, but correct use technologies and a precisely calculated power structure make it possible to obtain excellent results, especially if necessary to build combined walls in the bathroom during reconstruction, when some part old wall cannot be dismantled and it is necessary to connect the existing and new structures.
Use instead of traditional plasterboard gypsum fiber sheets, the strength of which is twice that of drywall. Bathroom walls made of gypsum fiber board can withstand significant loads and provide sufficient levels of heat and sound insulation. As practice shows, the widespread use of gypsum sheet systems is due to quite large advantages:
- Dry construction technology, which can be performed by a limited number of workers;
- Good heat and sound insulation properties;
- Obtaining a flat surface ready for final finishing;
- Opportunity to save money when independent execution installation;
- Possibility of hidden placement of communications;
- Light weight structure.
Plaster walls in the bathroom also have some disadvantages:
- the need for protection from direct prolonged contact with water;
- Difficulty in securing heavy objects.
Concrete walls in the bathroom
Until recently, during construction panel houses ready-made concrete plumbing cabins were used, which had only two advantages - ease of installation and a fairly large load-bearing capacity.
Thin concrete walls in the bathroom they do not have sufficient heat and sound insulation, but have the ability to increase vibrations. To improve the performance properties, it is necessary to either carry out additional measures, which can lead to a significant reduction in the internal space of an already small bathroom or the need to dismantle the existing cabin and erect walls from modern materials.
Plastic
Plastic walls in the bathroom can be used if it is necessary to create mobile or temporarily used objects. The lack of vapor permeability of most types of plastics, strong flammability with the release of toxic substances limits the use plastic walls in stationary conditions.
Conclusion
Bathroom. This is that small piece of our home that should not just be a place to install plumbing equipment, but be an island of comfort and coziness, where every thing is at hand, every lamp provides a unique ray of light, and even a seemingly lifeless wall radiates positive energy , filling the owner of the house and giving a charge of positive emotions. Every detail of the interior, every touch in the decoration of the walls, and even the walls themselves should be aimed at achieving such harmony.
When deciding what to make bathroom walls from, it is better to focus on the use of foam concrete and plasterboard systems with double cladding. It is these materials that provide a sufficient level of comfort and acceptable technical characteristics at low construction costs. And before you lay out the walls in the bathroom, you need to take care of preparing the base for future design, providing the required level bearing capacity and appropriate waterproofing.
There are special requirements for waterproofing for bathrooms and toilets due to high humidity and significant temperature fluctuations, especially in the shower stall. The sequence of work directly depends on the material used.
If waterproofing is carried out in compliance with technological requirements, the formed layer will last quite a long time.
Types of materials
- coating materials: mastics, varnishes, pastes, rubberized compounds;
- penetrating;
- liquid or bulk: solutions or mixtures;
- rolled, involving gluing or surfacing onto the protected surface.
For the floor, as a rule, coating or pasting materials are chosen, the basis of which is bitumen, polymer or rubber.
For a room it is better to purchase penetrating ones. Roll waterproofing It is rarely used here, as it requires special care in performing the work.
Which waterproofing will be used in a particular case depends on the scope of work and the area of application of the specific composition.
The characteristics of the material used in the construction of the building must be taken into account. For this purpose it is necessary to use non-flammable compounds. Brick is characterized by an increased ability of binding components; aerated concrete is characterized by high roughness.
Protecting drywall
Waterproofing the ceiling should begin with priming the surface to be protected. The composition should be intended for processing drywall, which is highly absorbent. Then a layer of mastic or water-repellent liquid is applied.
Waterproofing material should be not only on the surface of the ceiling, but also on the walls: where the shower cabin will be installed.
When using drywall in the bathroom you must:
- check the presence of gypsum board marks on each sheet;
- provide additional ventilation with regulator.
Sequence of work
In the most general case, waterproofing is performed as follows:
- Preparatory stage. The protected surface is cleaned from existing contaminants, traces of paint, and dust. The actual condition of the ceiling, floor, and walls of the bathroom is determined. Depending on the existing defects, a specific waterproofing material;
- Special sealing tapes are used to seal the joints in both planes. Special attention is given to the installation location of the shower cabin;
- The surface is primed. One composition is used for drywall, and another for aerated concrete;
- Waterproofing is applied taking into account technological requirements. Depending on the material used, it may be necessary to dampen or dry the ceiling;
- Finishing work.
Waterproofing barrier for floor
All work in the bathroom begins with the construction of a waterproof tray. To do this, the joints at the point of contact between the walls and the floor are carefully taped, especially where it is planned to install a shower stall. There is a high probability of direct contact with water.
If desired, you can immediately soundproof the bathroom. This will significantly reduce the noise level created by plumbing during operation.
Before starting work you must:
- remove old flooring and all dirt;
- repair existing cracks. For drywall it is worth using mastic and also processing antiseptic impregnation. For aerated concrete you will need cement-sand mortar.
To increase the adhesion of the waterproofing material, the protected surface is primed. The waterproofing material can then be applied using a suitable tool:
- paint brush;
- special spatula;
- burners.
The composition should form a uniform layer on the surface of the floor and 15-20 cm of the side walls. Where the shower cabin will be installed, the overlap can be much greater. After a day, you can begin laying the decorative flooring.
Is it worth protecting the ceiling?
Necessity of execution waterproofing works V in this case dictated not only by the risk of flooding the bathroom by neighbors above.
Without a reliable barrier on the floor in the apartment on the floor above, it will be difficult to prevent a flood. By protecting the ceiling, it will be possible to protect it from exposure to a humid environment.
Excess moisture can cause the bathroom to overlap and worsen appearance finishing material.
Work begins with preparing the ceiling surface by removing dirt and sealing existing joints. This is done using cement mortar if the house is made of aerated concrete.
For drywall you should choose more suitable composition, the main thing is to prevent direct contact between moist air and construction floors, especially above the installation site of the shower stall.
Such defects can cause loss of the formed layer protective properties, which will significantly worsen the performance characteristics of the formed coating. A waterproofing material is applied to the primed surface.
To protect a plasterboard ceiling you can use tensile structures, plastic panels, glass, mirrors. Becoming reliable barrier for humidity, they often act as a stylistic solution, harmoniously combining with the finish of the shower stall.
It doesn’t matter what material the walls and partition in the house are made of: aerated concrete or plasterboard, if high-quality implementation You may not remember the renovation work in the bathroom for 10 years.
Even if a certain amount of water spills from the shower stall onto the floor every day, you don’t have to worry about the condition of the building’s floors.
The common belief that aerated concrete absorbs some of the water like a sponge is due to its porous structure, which is formed during the production process. At the same time, aerated concrete holds the accumulated volume of water within itself.
The insignificant level of water absorption of aerated concrete is due to the fact that the pores in this material are not only closed, but also open. Cellular aerated concrete absorbs moisture by 6-8%, as it has the property of hygroscopicity. Considering this property of blocks, it is necessary to create additional protection from moisture. Protection of the material is provided not only for the constructed walls, but also during transportation and storage.
According to experts, in order to thoroughly destroy aerated concrete, it is necessary for the aerated concrete to remain in direct contact with water for a long time, i.e., the aerated concrete must lie in water.
Ready aerated concrete block consists of approximately 75% pores. Moreover, the largest volume is accounted for by macropores, which form rounded voids and interpore partitions.
The operational humidity of aerated concrete products is 4-5%. At the same time, the critical humidity for the material, which entails its destruction, for aerated concrete with a density of 400 kg/m³ is 45-50%. Similar indicators for aerated concrete with a density of 500 kg/m³ are 40%.
Thanks to its porous structure, the material “breathes” and, accordingly, has high thermal insulation and sound insulation properties. Absorption of large amounts of moisture leads to a change in these properties for the worse. To ensure that aerated concrete does not absorb moisture, additional processing is carried out.
It actively absorbs moisture from environment during rain, sleet, and also in spring when the snow melts. If you do not create protection, aerated concrete can absorb up to 35% of moisture relative to its weight. This percentage of moisture sharply reduces thermal resistance, and the rooms become damp and cold. Aerated concrete can crack in winter if the premises are not warmed up in the fall and the material has absorbed a large amount of moisture.
The humidity of aerated concrete used to construct the wall of a building depends on the number of seasons of operation of the house, on the design of the wall and sorption capacity. For example, the moisture content of aerated concrete walls country house, which is not used for residential purposes in the cold season, does not play any important role. If mineral material aerated concrete is protected from precipitation reliable roof, then in this mode of use of the building it will always be unharmed.
Moisture can enter the room from below from a poor-quality foundation or from the junction of walls with the ground surface; outside, with changing seasons, precipitation; from the inside in case of improper operation of the air conditioning system, flooding.
According to the manufacturers, a certain amount of water can penetrate shallowly into the material, however, it is the capillary-porous structure of the block that allows it to release moisture back quite easily and quickly, i.e., the liquid does not linger for a long time in the structure of wetted aerated concrete.
Aerated concrete easily releases the accumulated part of the water outside; when the air in the room becomes too dry, a wall made of this material will provide humidification.
The amount of water that penetrates into aerated concrete primarily worsens its thermal insulation properties. The higher the water absorption, the lower the actual thermal insulation properties of the material.
Aerated concrete walls, when saturated with water, create additional weight loads in the structures in which they are used. Accordingly, the higher the water absorption of aerated concrete, the greater the risk of an emergency.
The sphere of water itself is a destructive factor. The constant presence of water in aerated concrete can lead, at a minimum, to a decrease in strength.
Currently the greatest practical use We have found two methods to protect aerated concrete from water - waterproofing and hydrophobization.
Water repellents are compositions that are supplied in the form of concentrates or ready-to-use solutions, aqueous or organic solvents. They do not create a surface film, but form a water-repellent (hydrophobic) layer up to several millimeters deep. The vapor permeability of the treated surface is almost not reduced, i.e. some of the water evaporates but does not get inside. The surface treated with a water-repellent agent, as a rule, does not change color. A hydrophobic coating significantly increases the frost resistance of any material.
These properties allow the use of water repellents for silicate and ceramic brick, concrete and aerated concrete, limestone, travertine, shell rock, granite, marble and even paving slabs.
The water-repellent effect is due to the penetration of the water repellent into aerated concrete to a depth of 5 to 50 mm, depending on its density and humidity. The water repellent is fixed after 12-24 hours. At the same time, crystals form in the capillaries of the material, which prevent water from penetrating into the aerated concrete. But this does not prevent air from entering.
As for waterproofing, experts note: largely exclude negative impact water on aerated concrete helps the construction of the wall. Ideally, the “pie” of the wall structure should be such that the outer layer is significantly more permeable to vapors than the inner one. This will not only effectively remove some of the water from the premises, but also prevent water from entering the house from the street. For example, Indastro Renoart RSi240 will help solve this problem.
To prevent the blocks from absorbing moisture, use various ways protection. Osnovit SSL15 Safescreen insulation with antiseptic properties also performed well.
Treating the inner surface of walls with a primer deep penetration(acrylic primer Ekorum) followed by treatment with putty for interior works. This creates a vapor barrier. To create such a barrier, you cannot use traditional plaster without treating it with a primer and gluing it to the surface of the wallpaper. When using traditional plaster, the aerated concrete becomes damp from moisture from inside the room. The plaster is cracking and peeling. Treatment of the outside of the wall is carried out gypsum plaster, cement-sand is not suitable, as it peels off. Treatment with gypsum plaster is carried out once every 2-3 years.
Using exterior wall finishes decorative materials, for example, tiles, stones and so on. The decoration will protect the layer of plaster on the surface of the aerated concrete. Big choice decorative coatings.
Outer side lined with bricks. Pick up a brick. Since the cement-sand mortar allows steam to pass well between the brickwork and the aerated concrete wall, an air gap is left. The width of the gap is approximately half a brick. In construction in this way, one small problem arises: how to fix the facade wall if it is being built with a gap. The problem is solved using anchor elements, which are installed every 5 rows of laid brick. It is not recommended to use ordinary reinforcement or steel angles as anchors, as these elements are susceptible to corrosion. Over time, a tight connection between load-bearing wall and there will be no façade. The front wall will collapse. Fiberglass or stainless steel, popular on the building materials market, is used as anchors.
Finishing the facade with siding. The method is much worse than brickwork; it is not recommended to use it, since at the end of the work there is a lot of hidden problems. Of course, the finishing may look beautiful and the price is several times lower, but the durability of a building made of aerated concrete will decrease.
The use of reinforced concrete sandwich panels, which are based on shipbuilding concrete with a water resistance value of W.
Together with interior finishing and external walls foundation waterproofing work is carried out using aerated concrete, since moisture can penetrate through an improperly constructed foundation. To do this, when building walls, aerated concrete blocks are laid above ground level from 30 to 50 cm.
With quality equipment window openings, decorative ledges and roof drainage systems, as well as high-quality waterproofing basement, a house made of aerated concrete can stand for decades without the occurrence of any structural defects.
When carrying out construction work, do not leave aerated concrete under open air, since when it rains, moisture is absorbed very quickly and its properties deteriorate. It is not recommended to unpack the aerated concrete completely.
It is not recommended to build structures made of aerated concrete from November to March. During this same period, it is not advisable to plaster the wall surfaces. Excessive moisture will worsen the properties of the block, and when the plaster dries in a hotter, drier period, it will peel off and crumble. In this case everything plastering work must be repeated.
Gas and foam concrete are characterized by high vapor permeability, and this determines the nuances of selecting building materials for internal lining buildings. IN warm room There is always water vapor in the air, which easily penetrates deep into the aerated concrete wall, cools there and condenses. The block is getting damp. To prevent this, it is important to carefully select finishing building materials for the interior, whose performance vapor permeability should be much lower than at the walls. The same determines the choice of façade facing material, which must have even greater vapor permeability so as not to interfere with the free exit of moisture vapor accumulated by the walls to the outside.
Attention: Vapor barrier of walls made of aerated concrete or gas silicate is carried out indoors, and not on the facade. It does not matter whether the building is insulated outside or inside, or not, and whether the façade is lined or not.