A corner in a block house gets wet what to do. Why do the walls in the house sweat and get wet and how to fix it

The problem of dampness of corners and walls often worries both residents of high-rise buildings and owners of private houses. Due to the fact that the corner of the room is damp, the walls begin to darken, the wallpaper peels off, mold appears, the air becomes heavy in the room. Plus, in the cold season, the temperature in the rooms decreases, the windows are less often opened to ventilate the room, there is a lot of precipitation, and the walls themselves are not dried by the sun's rays.

Damp corners and walls are a serious problem that should be addressed immediately. Dampness in the room can cause various diseases, as well as become a collection point for fungi and mites.

Therefore, the question of why the corners in the house are damp worries many.

Sources of dampness in the corners of rooms are obvious and hidden. Some are easy to find, others will have to be searched. However, all the reasons why the corners in the house are constantly damp are divided into two subcategories - internal (poor ventilation, insufficient heating) and external (increased thermal conductivity of the wall, water penetration from the outside, etc.).

Often dampness appears in the corners of the room in such cases:

• there is a "leakage" of the wall (water can enter through cracks in the wall from the attic, drainpipes or eaves);
• the wall freezes (the corners "cry" from the fact that a "cold" bridge has formed due to the increased thermal conductivity of the walls);
• the heating capacity in the room is insufficient;
• there is no ventilation or it is ineffective;
• a fungus has formed on the walls;
• the foundation of the house is poorly waterproofed;
• there is a lot of washing and drying in the house;
• there are no hoods in the kitchen and bathroom;
• a void has formed in the seams not filled with mortar;
• the outer walls are too thin;
• voids have formed in the floor slabs;
• cooling occurs through metal beams or reinforced concrete structures;
• there is too much water and moisture in the basements;
• balcony slabs are poorly embedded in the wall;
• condensation appears on the ventilation pipes due to improper vapor barrier.

Eliminate dampness in corners

Attentive owners will always notice damp corners in time and establish the cause of sputum.

After finding the culprit of the problem, you can start fixing it:

• If the wall freezes, you need to take measures to insulate it. The most effective is It will not only reduce dampness, but also reduce heat loss. This is done either with mineral wool or foam. However, for apartment owners in high-rise buildings, such insulation is a rather troublesome business. If problems arise with external insulation, you can use the premises.

When applying insulation from the inside, thermal calculations should be made in order to avoid the appearance of condensation and moistening of the insulation material, as a result of which its insulation properties are lost.

• To make the correct calculations, the climate, the degree of thermal conductivity of the wall, etc. are taken, therefore, in such cases, expert advice is simply necessary.
• If the heating system is ineffective, additional sources of thermal energy should be used. It can be an electric fireplace, radiator or others, which are recommended to be installed in those places where there is the most dampness.
• If condensation appears due to excessive tightness of the room after installing plastic windows, the room should be ventilated more often.
• If the thickness of the walls is insufficient, it is recommended, if possible, to veneer the building from the outside with an additional ball of brick or apply insulation under the plaster. it is possible with a slab insulation (, mineral wool), placed on the frame with 5 cm walls for filling it with expanded clay. This building material will absorb moisture from a damp wall and prevent mold from spreading.
• You can improve ventilation by installing an additional hood, and even at the bottom of the door when entering a separate room, you can make a slot for air regulation. Ventilation should also be improved in the kitchen, which is most often a source of dampness.
• If present under the dwelling, moisture can penetrate through microcracks in the floor, as a result of which the walls become damp. To eliminate such a problem, the floor is treated with an anti-fungal agent, a moisture-resistant base is laid on it, and all the cracks are sealed with a sealant.
• If the cause of the damp corners is the fungus and mold on the plaster that has appeared in the wall, then all the affected areas are treated with antifungal solutions, plaster, if necessary, with a high-quality mixture, and only after that new wallpaper is glued.
• In case of poor-quality installation, moisture penetrates into the seams, therefore, the joints between the slab and the wall should be sealed so that there are no leaks leading to damp spots.
• When capping seams in external walls, care should be taken to ensure that closed and open joints provide air protection, and the latter, moreover, are well protected from moisture.

Damp corners on the upper floors of the building

In private houses or on the highest floors, the walls are often damp because of the attic.

This happens in such cases:

• the corners turn gray due to violations in the insulation of the attic, dampness and black spots appear most of all in places where the attic overlap is adjacent to the outer walls;
• the space of the attic is poorly ventilated (there are few ventilation holes, there is no through ventilation), with well-performed ventilation in the attic, the same temperature is maintained over the entire surface of the roof in the autumn-winter season.

Preventing dampness

Keeping dampness to a minimum and preventing its occurrence in the future will allow compliance with some rules.

• The laundry must be dried outside living rooms or with the hood turned on for air extraction.
• When cooking, pots and pans should be covered with lids to prevent steam from escaping.
• In the bathroom, where the concentration of humidity is highest, as well as in the kitchen, hoods and ventilation openings should be regularly cleaned from excessive debris, and these rooms should also be ventilated daily.
• In a private house, you can insulate the attic, as well as cover the walls with waterproofing material, preferably with pores.
• All flammable substances that form a lot of moisture, in particular, paraffin, are rarely used indoors.
• Ventilate all rooms in the house daily.
• Eliminate errors in the heating system in time.
• Use a dehumidifier to reduce humidity. This household appliance can easily cope with the problem of dampness, and its compactness will allow you to transfer the dehumidifier from room to room.

Reducing humidity

If the walls often get wet in interior rooms with high moisture (bath, bathroom), then the matter is most likely in the ventilation system. Therefore, first of all, you should check the ventilation holes for unnecessary objects that may interfere with air circulation.

It is easy to check how clogged the ventilation channels are: we bring the burning candle to the air vent and see how the flame reacts: if it reaches for the grate, then the channels are not clogged and there is a draft. When there is no reaction of the flame to ventilation, additional devices need to be installed in order to establish air circulation.

When the holes are not clogged, and the draft is still weak, then at the bottom of the door you can make additional slots for air intake. If this does not help, a forced exhaust is mounted in the ventilation duct. Such fans are turned on only when there are no people in the room, as they can greatly harm health.

Experts advise installing fans with a built-in humidity controller in the bathroom. When the moisture rises, the fan works automatically, eliminating the air saturated with dampness.

Some nuances of sealing joints

If the tightness of the seams is broken and when cracks appear in the walls, the corners in the room begin to damp. With this state of affairs, there is only one way out: the waterproofing of the joints between the panels must be repaired, and microcracks in the walls must be repaired.

After high-quality sealing, the walls should not pick up moisture. They can become damp and leak only when the technology of sealing the seams is violated.

The main mistakes are applying sealant without preliminary repair or using a low-quality sealant.

It should also be borne in mind: if the waterproofing of the joints is done in one apartment, and not in the whole house, then the problem of dampness will not disappear. Moisture will penetrate poorly sealed seams in an apartment on the floor above or on the technical floor, so although more slowly, it will find its way into the desired room.

Foundation waterproofing

It happens that dampness in the house is caused by the fact that the foundation is poorly insulated. With insufficient waterproofing, groundwater, when raised above 1.5 m, can penetrate the walls. In this case, they will get wet, mold will appear under the baseboard and in the corners, the plaster will begin to crumble, and the wallpaper will deteriorate. However, if the foundation is correctly made, then it will be able to prevent the penetration of groundwater.

Condensation after installing new windows

It happens that pockets of dampness in the corners of an apartment appear after replacing ordinary windows with plastic ones. The installed windows are very airtight, they tightly close the openings, as a result of which the ventilation of the room deteriorates. In such cases, you can avoid dampness of the walls if you know what to do.

Ventilation is often sufficient for air exchange in a room. However, if this is not enough, ventilation can be improved by placing an additional fan on the air vent. Then the humidity in the room will decrease, and there will be no condensation of moisture on the cold walls, in particular in the corners where the air exchange is reduced.

The problem of damp corners often begins to worry in the cold season. Many at first do not even notice the damp walls, however, when moisture turns into mold, the problem should be taken seriously. From constant dampness in the room fungi, mites and centipedes multiply, and the residents may develop various diseases, shortness of breath, cough, and allergic reactions.

Video: how to get rid of dampness in a house or apartment

The fight against excess moisture in the living space should be started immediately. This process is quite laborious, sometimes it requires money. However, with an accurate determination of the root cause of the increase in humidity and the correct choice of effective ways to deal with dampness, you can forget about wet corners forever. And if necessary, new repairs in the apartment will refresh the walls and delight everyone.

Brick is an excellent material, ideal for the construction of various objects - garages, office buildings and, of course, private and apartment buildings. But sometimes, after settling in, residents begin to notice that the wall of a brick house is getting wet. Black mold appears on the surface of the walls, the wallpaper peels off, the plaster damp.

Mold is a rather unpleasant gray microorganism that appears quite unexpectedly and is very difficult, but possible, to etch it out.

Causes of dampness

The reasons for the dampness of the walls in a brick house can be the following factors:

1. If the apartment is corner, the likelihood of dampness increases significantly, since unprotected walls will be subject to constant changes in temperature and cooling.
2. High humidity. In a brick house, dampness most likely comes from the basement.
3. If the wall is poorly insulated or insufficient waterproofing is done.

In any case, so that it does not get wet anymore, it is necessary to insulate the wall, as well as increase its waterproofing.

This is a much simpler and less costly way than buying a new, non-corner apartment.

The fight against dampness in the basement can not always be crowned with success, especially in old houses with an obsolete sewer system.

Tools you will need: level, hammer, tape measure, pliers, knife and others.

To prevent this problem, different types of devices are used. This also requires a variety of tools. Depending on the method, these are:

• roulette;
• level;
• a hammer;
• hacksaw;
• stapler and staples;
• construction thread or twine;
• trowel;
• spatulas;
• and others.

Heat insulating materials

When choosing thermal insulation materials in abundance on the construction markets and in stores, you need to pay special attention to the characteristics indicated by the manufacturer.

Some materials are intended for thermal insulation work from the outside of the house, others - for wall insulation from the inside. It is better for residents of a private house to insulate the wall from the outside, this will bring the greatest effect.

In an apartment building, it is not possible to insulate the walls from the outside, so you need to limit yourself to the internal processing of the wall. With the correct execution of work from high-quality materials, such processing will give the desired result.

• close attention should be paid to the water absorption coefficient. The ability of the heat-insulating material to absorb moisture directly depends on it. The lower the value of this indicator, the better its water-repellent properties, which is very important in a situation when the wall gets wet;
• the thickness of the layer of material that will be used as insulation varies depending on the degree of density of the material and the coefficient of thermal conductivity;
• thermal insulation with a low coefficient of thermal conductivity will take up the smallest space.

The soundproofing properties of materials should be of interest to those who suffer from too noisy neighbors or loud noises in the courtyard of the house. If the thermal insulation material has a high sound absorption coefficient, you can significantly save both time and money without additional repairs to install the sound insulation.

The flammability class of the material is also important. The safest material is class G1, since this insulation will not burn without an open fire.

There are several of the most popular thermal insulation materials:

1. The most common insulation, due to its cost, is mineral wool. However, if the wall gets wet, and you need to get rid of this problem first of all, and not just insulate the wall, then mineral wool is not the best choice. This material has a too high water absorption coefficient.
2. Styrofoam is used for both interior and exterior decoration. It absorbs little moisture, but has a low vapor permeability and does not allow air to circulate freely. When burning, it releases toxic substances into the atmosphere.
3. "Warm plaster" is suitable for wall insulation, both from the inside and from the outside. It has excellent sound insulation properties, does not absorb moisture, and has a low coefficient of thermal conductivity. The disadvantages of this material include a large mass, a layer of such plaster, due to its severity, should not exceed 50 mm and requires a reinforced foundation for a private house.
4. Cork insulation is used for interior work. Its thermal conductivity coefficient is even lower than that of "warm plaster", while the cork insulation is lightweight. Convenient to use, great for wall insulation, but it burns strongly.

External wall insulation

If the house is private, then it is better to carry out work on the insulation of the weeping wall outside, this will give the best result. For these works it is recommended to use polystyrene, "warm" plaster.

• for a start, the brick wall is cleaned of debris, dust and dirt. A layer of leveling plaster is applied, then the surface is primed. It turns out a prepared base for insulation. Styrofoam sheets can either be glued or fixed to the wall with dowels;
• if glue is used, then each sheet of material is carefully processed with glue, then the sheet is attached to the wall and pressed. You need to start this work from the bottom, lay the sheets in a checkerboard pattern, moving each level stacked higher relative to the previous one. The specified position of the foam sheets will help to strengthen the strength of the structure;
• glue is also used when fixing sheets with dowels, only it is applied to the foam plastic pointwise, preferably around the perimeter. Having lightly glued the material to the wall, a hole is drilled into it, into which the dowel is inserted;
• after laying all sheets in one way or another, the structure is fixed with a reinforcing mesh, plastered. Wall insulation ends with decorative finishing by painting or applying decorative plaster.

The simplest option from the outside is to use "warm" plaster. After cleaning the surface to be treated, it is primed. A plaster mesh is attached to the wall and heat-insulating material is applied. After the "warm" plaster has dried, the wall is decorated with tiles and paint.

Internal wall insulation

This is the best option for residents of an apartment building in the event that the wall gets wet. Cork, mineral wool, polystyrene, "warm" plaster are used as heat-insulating materials.

The material is chosen depending on the size of the wall, the financial capabilities of the owners of the premises, as well as for safety reasons. From this point of view, the use of foam plastic for wall insulation from the inside is undesirable, due to its high fire hazard.

Wall insulation from the inside can be divided into several stages:

1. Removing wallpaper, cleaning walls from dirt.
2. Impregnation of the wall with a primer.
3. Placing a frame made of metal or wooden slats. They need to be placed at a distance of 40 to 60 cm from each other.
4. Laying the selected material. If necessary, the sheets are cut so that they fit as much as possible into the frame openings.
5. Sheathing of the resulting structure with plasterboard, plaster and final decorative wall decoration (wallpaper, painting).

Waterproofing plaster

You can prevent the walls of the house from getting wet with the help of special drying plasters. This is a relatively simple and inexpensive way to significantly increase the waterproofing of a wall. Drying plasters can be used for both interior and exterior decoration.

Drying plaster material, mainly silicates, has a microporous structure. This structure does not allow salts to penetrate into the plaster, but crystallizes in the depths of the wall. Because of this, moisture does not rise above the level of the wall, but at the same time its natural evaporation is not blocked.

• drying plaster can be applied to old plaster, directly to brick, mortar. This material can be used at any stage of wall decoration - during the initial plastering, leveling the wall, exclusively for waterproofing;
• Before laying the waterproofing plaster, remove the wet layer of the old plaster and another 50 cm of the dry base. The surface for plastering must be flat, without cracks and chips, delamination is not allowed.

The ideal substrate is clean and slightly rough. Before application, the surface is wetted with water or primed. Special plaster is laid in the same way as usual. The layer thickness ranges from 2 to 4 cm.

A condition for using drying plaster should be the use of vapor-permeable decorative finishing materials, for example, paper wallpaper, silicate fabrics. There must be good ventilation in the treated area.

The problem of wet walls in the house must be taken very seriously, and if you run it, the consequences can be dire.

If the fogging of the walls has already developed into the formation of mold, then ordinary scraping is not enough here, since after a short period of time it will grow on the wall again, no matter what you process it. Here it is necessary to look for other solutions, namely, to get rid of moisture in the walls.

In order to find a solution to the problem, it is necessary to determine its source, and in a specific case, to find the reason why the walls in the house are sweating and getting wet.

Another important aspect, in order to localize the formed spot of moisture on the wall and prevent it from growing, a few primitive measures can help. First, you need to remove all obstacles to air circulation in that place (curtains, rags, etc.), and then put a heater with a fan directed at the spot (at least just a fan), this way you will slightly improve the situation.

What makes the walls in the house wet and how to deal with it

First you need to determine the source of moisture. There may be several options, we will consider each separately.

1. Freezing of the outer wall of a house or apartment

This option most likely refers to old houses, because before they only dreamed of good insulation during construction. Or, when building a house, they saved a lot on insulation, relying on a large number of batteries.

Signs: The house is constantly cold and damp in winter. The walls inside the room are very cold. A lot of energy is spent on heating in winter.

Why is this happening: In severe frosts, the dew point in the wall moves closer to the room, and with insufficient heating, the wall begins to sweat. In this case, we need to move the dew point closer to the street.

How to fix: In this case, you have two options, the first is to heat the room harder, but this is additional cash costs with dubious benefits, and second, it is necessary to insulate the walls of the house from the outside. To do this, you can try to insulate the walls with expanded polystyrene, for example. Under these circumstances, thermal insulation of the wall from the inside of the house will not help, but, on the contrary, will aggravate the situation. In this case, we will move the dew point even closer to the room. The moisture on the wall itself under the insulation will become even more, and it will gradually turn into puddles on the floor. Only external wall insulation can help here. With external insulation, we will shift the dew point in the direction we need, as you can see in the diagram. It is not very cheap, but reliable. And naturally watch out for ventilation. Wet walls cannot be avoided without ventilation.

2. The wall gets wet due to insufficient waterproofing

This option, in most cases, applies to those who live on the top or first floors of houses. If the wall is wet at the bottom, then moisture can get from the street through the basement, through the floor, basement, if there is insufficient waterproofing in those places. If the wall in the house gets wet or sweats upstairs, most likely, moisture enters through the roof that is poorly insulated from water.

Signs: The largest spots on the walls are in autumn, in wet weather, or in spring, when the snow begins to melt. If the room is well heated, then at subzero temperatures, wet spots will slowly dry out.

Why is this happening: With a poor-quality roof, water will always find a loophole and get into the interior of the room. And how does it rise to the top with poor waterproofing of the floor? The fact is that whether it is concrete, brick or building block, all these materials have a very bad property - to absorb moisture. A plinth, for example, can lift moisture from the ground by almost a meter. That is why waterproofing between the wall of the house and the basement is so important.

How to fix: In this case, you have only one way out. Find a place through which water enters the wall, and make the waterproofing better, or insulate the basement from the outside, if it's in it. Examining a house from the street will yield more results than looking for a solution from the inside. And of course, ventilation or frequent airing of the room in many cases will reduce the likelihood of problems with wet walls.

3. Poor ventilation of the room or part of it

This is a very common occurrence when the ventilation in the house is not sufficiently calculated, or does not work well. Even if she is normal, there are still corners in the house in which she “does not work”, and they start to sweat over time.

Signs: If there is a general ventilation problem, the windows may fog up a lot. With local - the wall in the house gets wet behind the curtain, or behind some objects that prevent air recirculation near the wall, and the rest of the walls are completely dry.

Why is this happening: With insufficient ventilation, no matter what you do, moisture will accumulate on the walls. In fact, there is enough moisture in the room for this, even if the air seems to be dry.

How to fix: With a general problem with ventilation, it is necessary to solve it. There should be circulation in the house. In case of a local problem in certain places, remove objects that interfere with circulation.

4. Recently renovated

If before the repair you were all right, and immediately after the repair the walls in the house suddenly get wet, then there is nothing terrible here and this is a common phenomenon.

Signs: The windows in the house sweat a lot.

Why is this happening: When you make a major repair using plaster, putty or other materials that contain water, the walls begin to absorb this moisture and this cannot be avoided. The repair is over, everything seems to be dry, but the moisture in the wall will remain in any case for some time. In addition to this, if during the renovation you did not ventilate the room enough, a huge amount of moisture will be in the air.

How to fix: During the repair, it is necessary to ventilate the room, and in the cold period it is also sufficient to heat it. At the same time, the walls will dry out soon.

Despite where the moisture on your walls came from, you must remember that starting this process is highly undesirable, and the sooner you find the source of the problem, the easier it will be to fix the consequences.

Hello! In the fall, we bought a private house, made of bricks, the walls with a well covered with expanded clay. Now the temperature on the street has dropped - 17, it began to get wet in the corners, they looked in the attic, everything was covered with slag, what should I do?

Galina, Kalachinsk.

Hello, Galina from Kalachinsk!

To answer your question, you should carefully examine the house and identify the root cause of the appearance of dampness.

Most likely, your sellers - home owners have encountered this problem, it would be good to ask them about it, if, of course, it is possible.

There can be many reasons for the appearance of dampness. This is the penetration of moisture from the bottom of the walls, right down to the foundation due to insufficient waterproofing, or even the complete absence of it. / Between the surface of the basement base and the lower row of brickwork, there should be a layer of roofing material or its analogs. /

These are leaks of rain moisture with its accumulation in expanded clay backfill. And leaks can be both through brickwork along loose seams, and from the roof of the house.

The option of insufficient thickness of the walls of the house is far from excluded, which leads to their freezing and the formation of condensation with the appearance of water inside the premises of the house. / The so-called dew point. /

There may be other reasons as well. But the above are usually the most likely.

What to do? The question is complex and depends on the identified reasons, first of all.

If moisture penetrates through the bottom of the walls, an attempt should be made, which implies installation between the walls and the adjacent soil of waterproofing. In practice, it most often looks like digging a small trench of possible depth in this place (about 30 centimeters) and installing a pair of layers of roofing material vertically, or better glass insulation. A good effect is given by smearing the vertical surfaces of the base of the walls with a primer, bituminous mastic. Starting from the very bottom (from under the surface of the earth and with a rise above it by several tens of centimeters.) This is done with a material heated to the maximum possible state (so that the same mastic in a metal container begins to bubble from high temperature).

This minimizes the possibility of ground moisture entering the bottom of the walls.

Other questions about condensation in rooms.

Many have seen the effect fogging windows in a house, in an apartment, in a car, or when a wall gets wet. And they asked ourselves the question: why is this happening? This is based on a simple physical process - condensation, in particular, of moisture from the air.
Although not only moisture can condense, but entire planets are formed in this way after a supernova plasma explosion. And this happens under certain conditions of temperature, pressure and humidity of the air at the moment. First you need to clearly understand what air humidity is.

We deal with air humidity.

Absolute humidity is the actual water content in grams in the vapor (gaseous) state in 1 cubic meter of air.

Maximum absolute humidity- this is the ability of air to dissolve the greatest amount of moisture in itself, to be saturated. Under normal conditions, it mainly depends on the temperature.

air temperature	-30	-20	-10	0	10	20	30	40	50	60	100
maximum moisture content gram / m3	0.3	0.8	2	5	9.5	17	30	50	80	130	600

Relative humidity- this is the ratio of the absolute to the maximum air humidity, that is, it shows how much steam is currently dissolved in the air, relative to its maximum possible content at a given temperature.

And this is where the main conclusions can be drawn. When it is minus -10 outside and the relative humidity is 50%, this means there is only 1 gram of steam in the air. In a house or apartment at an air temperature of plus + 20 and a relative humidity of 50% already contains 8 grams of steam in one cubic meter of air.

When ventilating a room, or simply by letting in such cold air into a warm house through ventilation, it mixes with warm air and is heated. But since new moisture is not immediately taken from anywhere in it, that is, take for example, we started half of the cold air, in which there will be about 5 grams of moisture, and it will heat up to 20 degrees, which means that the relative humidity in it will be only about 25% , which is not suitable for a comfortable stay, since air with such a low relative humidity will tend to take away (evaporate) moisture from our mucous membranes, the nose and throat will dry out, and the ensuing consequences.

Although in real conditions, due to life and the use of water in everyday life, when bathing, washing or cooking - that is, water sources, the relative humidity will be 30% -40%.

And the opposite situation, when warm air, for example +30 degrees with a relative humidity of 90%, that is, almost 30 grams of steam is dissolved in it, it meets cold and also saturated with steam air up to 90% and is cooled to a temperature of, for example, + 10, which can be maximally dissolve only 10 grams in yourself. Then all the rest of the moisture, that is, the extra 20 grams will precipitate. If it happens in the atmosphere, it rains.

Here are the main reasons why windows are sweating or a wall damp.

The first and foremost reason is because they are cold! And of course, basically, all over the house or apartment this happens only in winter. The bulk of the air in the room has a temperature of about 22 degrees and a humidity of 40%, that is, the moisture content in it is about 8 grams per 1 cubic meter. Cold walls, and even more so windows, do not have perfect thermal insulation from the external environment. Therefore, when it is freezing outside at minus 20 degrees, the temperature of the double-glazed windows can even be below zero degrees. If there is a multi-chamber profile and a three-chamber double-glazed unit, their surface temperature is unlikely to be higher than plus + 5 degrees.

Here is room air, which, due to natural air, comes into contact with a cold surface - it cools sharply, for example, to 0 degrees. And at this temperature, the air physically cannot dissolve in itself more than 5 grams of moisture, here its remainder of 3 grams and precipitates - it condenses on windows or walls and the wetting effect manifests itself, that is, a surface with such a low temperature does not have enough vibration energy to push moisture away from you. And with intense and constant condensation, people say walls or windows cry.

The second and also important reason is too high humidity - more than 70% at high temperatures. For example, this occurs when you boil water in the kitchen for a long time, or when you take a shower or bath, the temperature can reach plus + 40 degrees and humidity up to 100%. With such humidity and temperature, even walls or windows with an outdoor temperature of + 20 degrees will be at the dew point. This means that steam from the air will also condense on these surfaces. You can easily see this effect on the bathroom mirror, or when you just breathe on the mirror.

The same thing happens with the window in the car. You sit in a cold cabin and begin to breathe, one might say, hot and very humid air from your lungs. It is this moisture that settles on very cold windows in the car.

The third reason - I would call it hybrid. When the owners replaced the old wooden windows with new plastic ones. The old wooden windows had cracks, they did not have sealed double-glazed windows and therefore there was constant uncontrolled ventilation, which means that the house always had low humidity and low temperature. They did not fog up from this window.

And having installed new PVC windows, which are very airtight, while the walls remained cold, and feeling that it did not become much warmer, people, due to banal savings and possibly poor ventilation, simply do not systematically ventilate each room and do not use micro-ventilation , which is possible in almost any PVC windows. From this, the moisture had nowhere to go, and in some rooms there was constant high humidity, which condensed on cold glasses or walls, especially in the corners where there was a reduced air exchange. This means that conditions were created for the rapid reproduction of mold spores, fungus germinated and the corners or even all the walls began to turn black.

What do you need to prevent the windows from sweating and blackening the corners?

Wall activities. Primarily you need to insulate the whole house with high quality, the insulation layer is not less than 100 mm. For private houses with well masonry - it is best to fill the air gap between the outer and inner walls - .. This insulation has open pores, which means it has vapor permeability, which does not allow moisture to accumulate on the surface, unlike foam or polyurethane foam. In such a house, ordinary ventilation is sufficient.

For apartments, the best option is extruded foam, it is colored and much more expensive. It is best to glue it on a perfectly flat plastered surface, using polyurethane glue, which is applied around the entire perimeter, and preferably an area, so that it fits snugly and there are no gaps between the wall and the foam. And on the outside, plaster it with as large a layer as possible, in several passes and each with a reinforcing wall, especially the sunny sides to protect against atmospheric phenomena.

Window activities. No matter how many chambers there are in a double-glazed window or in the profile of windows, even with a maximum thickness of about 80 mm, they cannot insulate from the external environment as much as walls with a thickness of 500 mm! Why the windows will always lose the most heat, or rather cool.

The best option, even for new plastic windows - put two frames, as it was before, along the edges of the entire wall, so that there is the maximum possible air gap between the sealed windows. Better are two windows with single-chamber double-glazed windows, between which there will be an additional 100 mm of air, and in total it is about 200 mm, than one window with a five-chamber double-glazed window, with a total thickness of 80 mm.

Another variant - install modern shutters, or better insulated... Since in winter, the night is long, up to 16 hours, that is, we can reduce heat losses through the windows by an average of 10 hours a day, due to the additional air gap. The more insulated and airtight the shutters are, the better the window insulation will be.

And the last option, which is not very aesthetic, is cheap and practical. , or better with foamed polyethylene, which can be inserted from the outside between the glass unit with the frame profile.
For this, thinner sealing beads must be ordered. Foamed polyethylene has very low, which means good thermal insulation. With a thickness of 8 mm, it is comparable, and maybe even better than an additional whole chamber in a double-glazed window!

If the window is sweating from the inside or between the frames - it means that the tightness of the glass unit is broken. You can try to seal it around the perimeter with a sealant, pre-dry it in a warm dry room, or replace it with a new one.

Here are just such a house or apartment, to allow, without significant heating costs, to have warm walls and windows on which condensation will not fall out and to maintain, with the help of frequent ventilation or ventilation, the maximum comfortable humidity of 50% - 60%