Plastic windows perform their function perfectly: they retain heat perfectly, isolate street noise and maintain room temperature. But a common occurrence is the appearance of condensation on glass in cold season of the year. Why do plastic windows sweat in winter and how to fix this problem?
Causes and consequences of window fogging
The reason for window fogging is hidden in physical properties water. Being in a gaseous state, it is invisible, but as the temperature drops, the so-called dew point is reached, that is, water vapor turns into liquid. It is in this case that condensation forms and settles on the plastic windows.
The reason for moisture settling on glass is increased humidity.
If the windows begin to fog up from the inside, there can only be one reason - it’s a defective double-glazed window.. This element of the entire system must be sealed, and if this condition is violated, water vapor gets inside, where it settles on the inner glass as it cools. This problem is eliminated by replacing the glass unit, the frame can be left.
However, most often condensation forms on the outer surface of the window. Why do plastic windows sweat in winter and how to eliminate this factor? There may be several answers to this question:
Subsequently, fogging leads not only to disruption of the view through the glass. Often this process provokes the occurrence of worse phenomena:
- Freezing of windows and formation of ice on them.
- High humidity causes mold, rot and mildew.
- Water and low temperatures gradually destroy the foam in the gap and break the tightness of the entire system and the house.
Constant fogging of windows can lead to mold growth What to do with such a negative impact and how to eliminate the causes of window fogging?
Troubleshooting
If your windows are leaking, you need to determine the cause of the phenomenon. It happens that the situation arises as a result of placing a large number of indoor plants on the windowsill, which evaporate a large amount of moisture.
Window adjustment
You can verify what the cause is by doing a simple inspection of the entire window. The first thing to do is to check the correct adjustment of the valves and the degree of their locking. This is done as follows:
- You can feel a strong draft by running your hand along the window.
- Light a match or candle; if the light fluctuates, the seal is broken.
- Paper is placed in the door and locked. You can pull out the sheet without any effort.
If deficiencies are found, proceed with adjustment. The sash is adjusted vertically and horizontally with screws located on the lower hinge.
To adjust the sashes, tighten the bolts located on the lower hinge The degree of pressure is adjusted by eccentrics at the ends of the window, as well as by tightening the pressure plates.
Switching to winter or summer mode is carried out using eccentrics Don't forget about seasonal window adjustments. To do this, turn the regulators with a marker inward in the summer, and toward the street in the winter.
Window sills
Windows often cry due to improper air circulation during the cold season. The reason is hidden in the wide window sills, which block the access of warm air masses to the surface of the glass unit.
In this case, to normalize circulation in the window sill, you need to drill several holes that will ensure normal heat access to the glass.
Holes in the window sill allow warm air to warm the glass You also need to pay attention to the grilles covering the heating radiators; perhaps they also impede air exchange.
Slope finishing
If the window was installed incorrectly (leaky gaps, the frame has moved), then you should contact the installation company. Installers are required to fix this problem free of charge.
An independent attempt to seal the gaps may not correct the situation, since the double-glazed window was initially installed incorrectly.
Finishing and insulation of slopes prevents windows from fogging The situation is different with slopes. If finishing has not been done, it must be done immediately, otherwise it will lead to complete destruction of the polyurethane foam in the gaps. To prevent windows from crying, it is best to additionally insulate them using heat-insulating material (mineral wool, foam plastic or penoplex).
Accessories
Quite often, windows cry due to poor-quality or worn-out fittings. All mechanisms must function normally and smoothly close the sash while maintaining normal pressure.
Damaged seal must be replaced The seal must be carefully inspected. It should be elastic, without tears or cracks. If there is damage and elasticity is lost, proceed to replace it.
Ventilation
Ventilation of the room must be approached very carefully. This is especially true for rooms with high humidity levels (kitchens, bathrooms), where glass most often sweats in winter.
After all, plastic windows completely seal the room and make it difficult for air to enter from the street. The problem of air exchange can be solved in the following ways.
Check existing ventilation for blockages. This can be done by lighting a candle near the channel outlets. If the light does not deflect, then the hood does not work. The gratings are removed and cleaned until normal operation is restored.
However, in addition to the exhaust system, there must also be supply ventilation. This issue can be solved by installing ventilation valves on the windows.
Supply ventilation can be provided using the valve built into the handle Today there are modern supply systems installed in the window handle; they do not spoil the appearance and provide a sufficient amount of fresh air.
By ensuring a normal level of ventilation, the problem of high humidity is eliminated.
Thermal insulation
Single-chamber double-glazed windows are used in most non-residential premises where thermal insulation is not so important. If such a double-glazed window is installed in a living room, it will not provide adequate heat conservation.
Thermal insulation of glass with film will not solve the problem of cold The problem can be eliminated by insulating the slopes and applying an energy-saving film to the glass. But these measures will not ensure full heat conservation.
Optimizing humidity levels
As mentioned above, this phenomenon can be eliminated by ensuring normal ventilation of the rooms. However, if this does not help, then you can install moisture-absorbing devices under the window sill. Such cartridges are inexpensive, and their efficiency is quite high..
Recent renovations can increase indoor humidity. A large area of plastered surfaces evaporates a huge amount of moisture, which ventilation cannot cope with. This is a temporary phenomenon and as the walls dry, the humidity level returns to normal.
As a rule, these are the main reasons why windows cry in winter. Once they are eliminated, the situation will normalize and there will be no problems with fogging.
Of course, we all know very well that metal-plastic windows and doors can retain heat in the house much better than wooden ones.
Since wooden ones can allow cold air to pass through the gaps between the frame itself and the glass, just like the wood itself excellently allows air to pass through.
But any wooden frames - be it balconies or windows - have one undeniable advantage, and this advantage lies in the fact that they are made of natural material - wood.
The same, unfortunately, cannot be said about metal-plastic structures.
Yes, they do not allow cold air to pass through, but at the same time the process of air ventilation in the room is disrupted. 
Preparing a sleigh in the summer
When carrying out renovations indoors, you need to think about increasing thermal insulation, which will save your money in winter, and about proper ventilation, which will protect you from dampness and mold. By considering all of the above and some other possibilities when repairing and replacing indoor windows, you can save time, money and health.
When replacing windows in summer period You may not encounter a condensation problem. IN summer heat the room is almost constantly ventilated, air circulation is excellent and, no matter whether it is damp outside or not, moisture on the windows can only be seen when it rains. With the arrival of cold weather, the problem becomes obvious. In the absence of heating in the fall, we often cannot ventilate the room - saving heat and trying to close ourselves off from the weather. This process inevitably leads to increased humidity indoors, which in turn will invariably affect your glass.
Where does condensate come from?
It is the tightness factor, but only in conjunction with a violation of heating and air convection in the room, that causes the formation of condensation. Condensation begins to appear on the glass when the room temperature drops below +18 degrees. As a rule, it begins to actively appear in the autumn winter period when the heating is on and the temperature outside is much lower than inside.
How does heating affect condensation?
Have you noticed drops of condensation on the glass? Typically, moisture appears in the corners of frames or at the bottom of the glass. Most often, the appearance of moisture indicates insufficient thermal insulation of the room, or deficiencies in the heating system. By thoroughly approaching the solution to this issue, you can get rid of water droplets on the glass forever. “Drying” the window surface is quite simple; to do this, you need to install an additional heating radiator in the room. This way you will increase the room temperature in winter and your windows will no longer be covered with drops of moisture.
We fight condensation by insulating walls
If it is not possible to install a radiator for technical reasons, you can consider insulating the walls from the inside. True, in this case you will have to repair the walls in the room, but your costs will pay for themselves in the next heating season. Another solution could be external wall insulation. However, to do this you will have to hire professionals to do it. high-altitude work. However, the effect of such insulation will be double. In winter you will keep warm, in summer you will keep a cool atmosphere in the apartment. And most importantly, if you live in a private house, do not forget about insulating the attic, since it is through it that a huge amount of heat escapes.
Good ventilation prevents moisture loss!
However, you can think about the issue of indoor air ventilation in advance. Forced ventilation devices will help you, which you can install in ventilation grilles during repairs. Also, when ordering metal-plastic windows, you can provide the opportunity to set the window to micro-ventilation mode, or order a ventilated double-glazed window profile. Heating radiators, as we have already said, must be taken care of in advance, without blocking the access of hot air to the room. Knowing that the room is often damp, try to minimize the presence of flowers in the room.
Mold and mildew removal products
Answering the question of what to do and how to get rid of mold on windows, we will consider all possible combinations of actions. The most common ways to remove fungus on plastic windows are the following:
- Mechanical methods for eliminating fungus:
- mechanical cleaning,
- ultraviolet irradiation, carried out using professional irradiators,
- alternatively, the affected areas can be treated with a quartz lamp,
- heat treatment with a stream of hot dry air - for example, using a hairdryer.
- Treatment of affected areas by special means, for this the following are traditionally used:
- Long-acting fungicides - they are used to treat window openings, resulting in the disappearance of mold and mildew on installation seams and window slopes guaranteed for 5 years.
- Bleach solutions are also very common and are used to permanently remove fungus on the slopes of plastic windows.
- Among the folk remedies for killing mold, the most common are hydrogen peroxide, vinegar, citric acid, copper sulfate, and boric acid.
- Separately, it is worth noting this product based on sodium perchlorate - not only is this substance itself dangerous for humans, it is completely unsuitable for treating porous surfaces, for example, window slopes made of plasterboard.
- From modern means tea tree oil can be noted, which is very economically used and is suitable for treating areas large sizes. It is enough to dilute 1 tbsp. oil in 1 glass (standard, 200 ml) of water, pour into a spray bottle and thoroughly treat the areas affected by the fungus. Having removed the plaque, there is no need to thoroughly rinse the product in the future. Grapefruit seed extract is used similarly.
- Remedy from copper sulfate(100 g), bleach (100 ml) and water (1 liter)
- Good old alcohol is also used for disinfection.
- If the depth of the damage is high and the fungus has penetrated into the concrete, you will have to remove the damaged part using a hammer drill or spatula.
Preparing and treating mold-affected surfaces
As a rule, fungus is eliminated quite simply. You will need:
- Thoroughly rinse and clean the affected surfaces, trying to remove as much mold as possible,
- Prepare and apply the fungicidal agent or other substances recommended above,
- Rinse it off thoroughly with water,
- Dry the treated area thoroughly - it is best to use a dry rag for this (you need to throw it away later), and then use a hairdryer, which will thoroughly dry the surface with a stream of hot dry air.
This algorithm applies to cases where traces of fungus were found on windows.
But what to do if fungus appears on the slopes of plastic windows? In this case, the following cleaning measures should be carried out:
- First we disassemble the slope,
- We additionally insulate existing voids polyurethane foam, the excess of which must be cut off after hardening,
- We treat with any fungicidal agent or bleach solution,
- Dry the treated area
- We are restoring the slope.
If dark spots begin to appear at the joints, you need to proceed as follows:
- First we clean the joints,
- We check whether the mold has gone even deeper, down the slope,
- If not, dry the joint, treat it with bleach,
- Dry thoroughly
- We apply a suitable sealant, treating all slopes and joints with it,
- We finally restore the joint.
If the root cause of mold appearing on window slopes is high humidity, there are several recommendations for eliminating the problem:
- If the window sill is too wide, holes are made in the window sill itself and plastic grilles equipped with blinds are installed to improve ventilation. Such gratings can be found in almost every hardware store. They perform the function of directing air away from heating battery to the window.
- To control the level of humidity, special hydraulically controlled ventilation valves are installed at the top of the window, capable of automatically opening when the humidity level rises. It is thanks to such valves that continuous air flow and a noticeable reduction in humidity in the room are ensured.
- As a last resort, additional ventilation system- for example, an air conditioner with a filter made of fungicidal impregnation, which helps destroy mold spores.
Prevention of occurrence
If there is no mold or mildew on your windows, this is not a reason to relax and forget about its possible appearance. Therefore, it makes sense to take an interest in preventive measures in advance, which include:
- Constant fight against dust
- Control of humidity in the room, preventing its excess (especially with leaking pipes, a large number of indoor plants, etc.),
- Availability of air conditioning and ventilation systems,
- Maintaining a stable microclimate (humidity not higher than 60%, and the air temperature in the room is approximately 22-24 C),
- If you have not yet installed PVC windows, before starting installation you need to treat the window opening with any fungicide - you can buy it in every construction market.
- Keep kitchen and bathroom vents open to ensure good air circulation.
- Check that the window frames are working properly and are not damaged. Fix damage immediately.
- It is advisable to keep interior doors open.
- Ventilate the apartment 1-2 times daily.
- Do not dry clothes indoors with the windows closed or on radiators.
- It is preferable to use moisture-resistant materials for finishing the apartment.
- If you have previously encountered fungus on windows, it makes sense to treat potentially dangerous areas monthly with a solution of some fungicidal agent.
- When installing plastic windows, it is recommended to install a built-in ventilation system in them.
In the article we discussed everything related to fungus on PVC windows and the fight against it. It remains only to advise readers to remove fungal deposits immediately after detection, without jeopardizing the health of their loved ones and themselves.
Glad you came to see me again!
This winter my teeth hurt. It’s not clear whether it’s the paste or the water, but one even broke down altogether. While he was solving the problem through visits to the dentist, he noticed how much the windows in his office fogged up. Therefore, today I will tell you how to deal with the formation of condensation on plastic windows.
Condensation on windows: causes, methods of combating
The most accurate diagnosis of the causes is carried out using a television examination. In general, the classification of the reasons due to which “fog” settles on glass includes four points.
The problem occurs due to the following factors (one or more):
- the microclimate of the room has been changed;
- incorrect choice of window design;
- installation technology is broken;
- defective glass unit, frame.
I propose to study in detail the problem of foggy PVC windows in order to know how to effectively deal with its causes.
The microclimate of the room is disturbed
What requirements does the Sanitary and Epidemiological Station put forward for the microclimate of residential premises?
The most comfortable living conditions are +18+23 0 C, 40-50% humidity and an air exchange rate of 3 cubic meters per “linear” meter of the room, if it is used for relaxation and leisure time.
In kitchens, air exchange should be 2 or 3 times faster(with electric and gas stove respectively). From these recommendations it follows that a living space can be considered comfortable not only when it is warm, but also if a sufficient amount of fresh air enters it.
Ventilation device
The apartment's domestic ventilation system is installed in the kitchen and bathroom. To the other rooms Fresh air enters during ventilation and through microcracks in frames. With the arrival of winter, in houses with ordinary wooden frames, natural micro-ventilation is blocked by covering the window panels with paper strips. But even with such protection, windows rarely fog up. After PVC installations double-glazed windows, the situation changes dramatically if the designs are chosen without taking into account the characteristics of the regional climate or errors were made during the installation process.
What is the essence of such a phenomenon as window fogging? There is a certain amount of moisture in the airspace. And if it comes into contact with a surface whose temperature is less than the “dew point”, then condensation will form. If such a surface turns out to be window glass, then it fogs up. The degree at which condensation forms is not constant. The dew point is more closely related to the ratio of the air temperature in the room and the saturation of the air with moisture. The higher the last one and the lower the first one, the higher the dew point.
Let’s assume that the temperature in the room is stable at +15 degrees, then condensation will begin to form at +13.38, +7.30, +1.53 if the air humidity is 90, 60 or 40%, respectively. Therefore, it is somehow not surprising that windows always fog up in damp and cold rooms.
But where does the water on the glass in your home come from? We will further examine the issue of condensation formation on PVC windows.
Condensation appears under different conditions and depends both on the factors mentioned above and on the processes of our life. After all, while we are outside the home, the level of humidity in it is the same, and as the home fills with households and in connection with our activities under the roof of our home, the amount of water in the atmosphere of the premises begins to increase.
Here are the approximate volumes of water formed per hour at:
- breathing - from 40 to 90 g from each person;
- the presence of growing flowers - up to 10 g from one small bush;
- cleaning and during cooking -1000 g;
- taking a shower or bath – up to 2600 g;
- when washing by machine – up to 300 g;
- the presence of a medium-sized aquarium - up to 200 g.
How much water is contained in construction mixtures that were used to decorate your home, under washable wallpaper? Moisture can be stored inside such objects for up to two years. If the air in the apartment rarely warms up above 17 degrees in winter, then there are all the conditions for the formation of condensation in the cold season.
About the causes of condensation on windows in the video:
https://youtu.be/q6vLSYtbu7Y
How to avoid this unpleasant phenomenon?
Here are a number of proven methods that need to be taken at least a couple of times a day:
- keep the window slightly open for a long time to dry the air in the room(option only for apartments with good heating);
- open wide all the windows in the apartment for a quarter of an hour(a lot of heat will not escape, unlike moisture);
- arrange two-minute ventilation by opening the windows and front door (make sure that with such a drastic change in the humidity level, all open elements frame structures and the door was securely fastened, and did not slam, threatening to crumble).
At the same time, do not forget to make sure that warm air from the radiators it flows not only into the room, but also to the frames, and the curtains are some distance away from the edges of the window sills.
Mistakes with choosing PVC windows
If condensation is tormented, and the windows are plastic, then you can eliminate the problem by replacing conventional structures with energy-saving ones.
But only on the condition that the installation will be carried out by a specialist, and not by a “comrade from the street.”
Problems due to technology violations during the assembly of double-glazed windows
If you attach a defective glass to glass sealing rubber or incorrectly install some elements of window fittings, then an expensive double-glazed window will not meet the owner’s expectations. In some such cases, the problem can be eliminated by properly adjusting the fittings.
Problems due to illiterate installation and design of slopes
Are you 100% confident in the window manufacturer? Then the reason for the “fog” on the windows may lie in poor-quality foaming of the frame or a poor vapor barrier coating. Sometimes builders completely “forget” about the last factor due to ignorance of the process correct installation waterproofing in window construction. That is why I always insist that you, my reader, trust the installation of windows only to professionals and advise other people to do so. Correcting mistakes made when installing PVC frames in openings is very difficult.
Reasons for “tears” and “sweat” on windows
Condensation on window glass can form both in structures with PVC panels, and with wooden ones.
The main reasons for “foggy” windows:
- cold season;
- a large amount of moisture in the atmosphere of the room;
- window design with poor thermal insulation.
You can’t cope with the cold outside, so either influence the level of humidity in the room or change the double-glazed windows to modern ones. Moreover necessarily with enhanced thermal insulation (with a special coating, with double chambers).
You shouldn’t think that only modern windows sweat. Condensation appears on any windows. And the type of material used to make the profiles is not the main reason. It's all about the tightness of the window structure.
The same Finnish windows with a wooden supporting frame and double-glazed windows sweat several times less than windows according to the European standard, but with one chamber. This happens due to the different thermal insulation properties of the products - in two-chamber windows, thermal energy insulation is better.
When I was younger, in my house, and in all houses of that time - with rare exceptions - the window frames were wooden, the glass rarely fogged up. But if modern seals were installed in those structures to ensure tightness, then the windows would “cry in three streams.”
Why does this inconvenient phenomenon occur in everyday life?
There is always water vapor in the air. As the temperature rises, the amount of moisture in the air increases. As soon as you bring something cold into a room with an atmosphere, saturated with moisture, an invisible “casing” of colder air forms around the object. This temporary shell does not have the ability to hold as much moisture as the rest of the air in the room does, so the surface of the introduced object quickly becomes wet due to “dew.”
The more water in the atmosphere, the less “demanding” moisture is regarding the temperature level of objects on the surface of which it can fall in the form of condensation. Those. they no longer need to be the same temperature as, for example, vegetables in the refrigerator or bottles of drinks . If the air saturation with water is about 100%, then the steam will begin to settle on all bodies whose temperature differs by a degree, or even less, from the temperature of the atmosphere itself.
The manifestation of the so-called dew point occurs when a certain relationship is formed between the air temperature and its humidity.
Approximate data can be obtained from the table below.
When the inner glass in the double-glazed window chamber has a temperature that is the same as the value at which the race point is formed or lower than it, and the air humidity inside the structure also corresponds a certain parameter, the glass begins to fog up. That's why “Tears” on the window indicate strong air humidity inside the house.
Possible reasons for this:
- the result of your daily activities in the apartment;
- disrupted ventilation process;
- problematic glass unit;
- violation of the technology for installing a glass-transparent structure in a frame opening.
If the essence of the problem is poor air conditioning, then take the manifestations of condensation as a call to ventilate the room. But if, after ventilation, the glass soon becomes cloudy again, and frequent opening of windows leads to excessive consumption of thermal resources, then it makes sense to stabilize the ventilation system and, perhaps, find a replacement for the existing double-glazed window.
Choose a new design taking into account the typical temperatures for your region during the cold season.
If a drop in the mercury thermometer to -20 is a completely standard phenomenon for winter, then purchase a double-glazed window taking into account the dew point and the level of humidity and heat in the room that is comfortable for your family. If acceptable air humidity is about 60%, and you try to keep the air temperature around +20, then under such conditions the dew point is +12. At the same temperature, but 40% humidity, the dew point is +6.
How can the relationships I just described be used in practice?
When studying the range of double-glazed windows, pay attention to the indicator with the C/W value. With the above described initial data (-20 outside, +20 in the room and humidity at 40%), the thermal insulation index of the window structure (Ro) should exceed 0.35-0.36 m2°C/W. With an increase in humidity, say, up to 55%, the lower maximum permissible value is Rо = 0.54 m2°C/W.
What else do you need to remember when choosing a double-glazed window?
If Basic structure with a spacer frame made of aluminum, then at the edges metal products Cold bridges will form.
Because of this, when it gets colder, condensation may form on the glass near the lines of contact of the transparent elements with the aluminum profiles.
Additional measures to reduce the likelihood of condensation forming on the glass of PVC windows:
- find out whether near all windows the heated air from the radiators reaches the glass(a strongly protruding edge of the window sill and close placement of curtains can interfere with the process);
- ventilation valve installation, which allows portions of fresh air to reach the surface of the glass, also helps fight the formation of condensation.
Let me summarize my “lecture” on the topic of combating condensation on windows.
Tips for combating condensation and mold on PVC windows in the video:
https://youtu.be/BotwVGyYUwA
How to deal with glass fogging?
It is best to navigate the choice before installing new double-glazed windows in window openings desired design The data from the first table will help.
Having determined the appropriate tp (dew point) level, tell the manager serving you that you want to buy a double-glazed window with a tp value higher than the parameter you found in the table. To protect yourself from the order executor ignoring your request, ask to include it in the contract and make sure that this is actually done. If they are really stubborn, then maybe it’s worth changing the order executor? Why would you buy a double-glazed window whose technical characteristics will be similar to those of the structure it is replacing?
Everything was sorted out, the glass unit was correct, the installation was done according to the instructions. But bad luck: with the advent of cold weather, light “clouds” of condensation appeared near the profiles. What to do? Change again?! No. Small spots are natural and not problematic, unlike what I will talk about below.
What is happening secretly from our eyes:
- camouflaged decorative slopes window openings have cold bridges, due to which moisture gradually accumulates under the panels, which can provoke the growth of mold and the loss of the technical qualities of the insulating gaskets);
- the slopes themselves prevent warm air from reaching the surface of the glass(you can see the solution to the problem without damaging the appearance of the window on the page about preventing the appearance of moisture on windows);
- Soviet windows are remembered for the number of cracks from which it blew mercilessly during the cold season - however, these micro-holes participated in the process of natural ventilation of apartments, which disappears when installing sealed metal-plastic windows (a significant problem that requires the urgent invention of a new effective ventilation scheme for residential premises).
The windows first “sweat” and then become covered with an ice crust
Few apartment owners with metal-plastic windows I have not encountered any condensation on the glass. Such untidiness happens for various reasons. And even a professional is not always able to quickly determine where the “legs” of such a problem “grow” from. Identifying the causes requires some knowledge of physics and practical experience. But eliminating the reason why the windows “cry” will help you forget about such a phenomenon as foggy glass for a long time.
Explanation of the cause of window fogging from the point of view of physicists
When a window fogs up, you are seeing the actual result of atmospheric moisture being converted from vapor to liquid form due to exposure to low temperatures. After all, cold air is not able to hold much water, so its excess settles on everything that has a lower temperature than the air. If the window glass is the coldest part of your apartment, then this is where moisture from the cooled air will settle.
With significant volumes of condensate formed, it becomes a problem. Not only that building construction moistened, mold may also appear. And if there is severe frost outside, “icebergs” may even grow on the window. And all because of the high humidity!
However, excessive dryness of the atmosphere leads to health problems.
So how should you behave in order to get rid of condensation on the windows, but not harm yourself and your loved ones? Use the old-fashioned method - ventilate more often.
Why are there no problems with condensation in apartments with old-style window designs?
Double-glazed windows are sealed and do not give air flows outside the window a chance to penetrate into the room. Because of this, natural ventilation of apartments disappeared, which, by the way, was taken into account as a phenomenon when designing buildings. And the air masses, even if they penetrated through the cracks in small volumes, dried the air in the rooms and prevented condensation from forming on the windows. With the replacement of conventional window frames with modern ones, not necessarily with metal profiles, but with a sealed vestibule, natural ventilation stopped, and excess moisture began to settle on the glass.
To achieve normal humidity in a room, you need to either systematically ventilate it yourself, or entrust this process to the windows, equipping them with double-glazed windows with delicate ventilation systems. Then the microcirculation of air masses will be restored and the windows will stop “crying”.
Additional factors affecting window fogging
Very often, an excessively wide window sill is to blame for the formation of condensation., preventing warm air flows from radiators from reaching the vertical surface of the window opening. The presence of several flowerpots, which are also sources of moisture evaporation, only aggravates the problem. Is there no possibility for normal convection? Then get ready to run with a cloth from window to window and open the window more often.
If, in addition to the fact that natural ventilation does not occur due to the tightness of the window, and even the hood is broken or completely absent, then you will encounter window fogging almost all year round. So a kitchen hood over the stove is not a whim of the wife, but a useful household item that maintains a normal level of humidity in the house. Don't forget about this device when you start repairing - you shouldn't turn it on when the wallpaper has just been pasted. But activate it more often later, when the repairs are completed - even when you are not preparing food.
Even more tragic consequences occur in those apartments where the owners incorrectly reconstructed or even completely dismantled the existing ventilation system. Condensation and freezing of glass will not keep you waiting. Although such a nuisance can also happen in an apartment with a hood - if cheap double-glazed windows are installed that are not capable of providing good thermal insulation.
For example, in the northern regions, single-chamber double-glazed windows can only be built into partitions indoors. For window openings External walls require two-chamber structures with three glasses. And it is desirable that one of them be an energy-saving “I” or “K” type. Such glass not only reduces the risk of condensation, but also helps to avoid excessive consumption of heat resources.
To make you understand the difference between a regular double-glazed window and an energy-saving one, I will give an example, talking about a standard metal-plastic window and a single-chamber window, but with i-glass. Using a pyrometer, I will obtain temperature data.
Measurement result (regular double-glazed window with a thermal insulation property of 0.54 sq. m. C/W):
- in the room +22.7;
- outside -17.2;
- near the glass +14.
Measurement result (single-chamber heat-saving double-glazed window with a heat-insulating property of 0.64 sq. m. C/W):
- in the room +22.8;
- outside -17.5;
- near the glass +19.
As you see, A single-chamber double-glazed window can be more efficient than a double-chamber one in terms of energy conservation.
If any features in modern windows, why do the latter “cry” and become overgrown with ice when frosts arrive?
Yes, the aluminum spacer has a lower temperature than the rest of the window. That is why condensation occurs most abundantly near the edges of double-glazed windows.
I think that this problem is unknown to you if the humidity level in your apartment is within 60%, there is properly functioning ventilation and you heat your home well. But if one of these conditions is not met, then remember the rationale: order a double-glazed window with a polymer spacer frame. This material will not allow cold bridges to form, and therefore condensation will not fall out. If there is no condensation, then there will be no ice on the glass either.
Another reason for the formation of condensation on glass is the residual effects of recently carried out repairs. Therefore, if a new double-glazed window was installed during a period when the room or the entire territory of the apartment was updated using some kind of construction work, or you have moved into a new building, it is not surprising that condensation appears on the windows. And the quality of the glass unit has nothing to do with it.
Newly erected concrete or brick walls are an additional source of moisture for 2 years. Slowly but surely, seemingly dry surfaces release water through microcracks, and it is impossible to resist this process. It is wiser to adapt to it by using moisture eliminators, using frequent ventilation and double-glazed windows with pre-installed ventilation elements. Without all this in apartments of new buildings excess humidity air, affecting both well-being and the transparency of windows, will be present for at least a year. Especially if you live in a region where summer is not characterized by an abundance of sunny and really hot days.
And I don’t think you’ve thought at all about the connection between condensation on the windows and the side of the world they face.
It turns out that the glass of northern windows does not dry out from condensation longer than southern ones.
About methods for eliminating condensation on plastic windows in the video:
Mistakes during installation and construction work
It’s a shame, of course, if, having spent money on purchasing high-quality double-glazed windows, you do not get the expected result after installing them due to errors in the installation of structures. Therefore, I strongly advise you to hire only qualified installers.
Typical installation errors:
- insufficient filling of the assembly seam construction foam (the layer will thin out under the influence of moisture and wind, which immediately or over time, depending on the thickness of the seam, will lead to a decrease in the thermal insulation properties of the structure);
- non-compliance with recommendations for the design of junction units leads to the formation of “cold bridges”, which in winter will contribute to the formation of condensation;
- unfilled seams between walls are found not only in buildings built under the Soviets, but also in more modern ones (if such a problem is discovered during the installation of a window structure, the hole must be filled with polyurethane foam so that the double-glazed windows are not exposed to unwanted contact with cooled air in the area of the junction points).
The easiest option for eliminating condensation
The old way of freshening the air in a room by ventilation works best with excess moisture in the room air. By accustoming yourself to opening the window several times a day, you are guaranteed to protect your windows from condensation., and the room from mold and musty atmosphere. Then there will be no need to change or upgrade existing double-glazed windows. You will be free from the obligation to update them until the service life of the structures ends!
If there is a desire to replace windows, then I advise you to opt for two-chamber products. When replacing a balcony door with a plastic one, a single-chamber door can only be installed if the balcony is glazed. Otherwise, with the arrival of winter, condensation on the glass, and then ice, will not be avoided. And yes, make sure that the new or old window sill does not block the access of heat from the radiators to the surface of the windows.
Determine the duration of each ventilation taking into account the humidity of the room air. If there are no pots steaming in the kitchen and the washed clothes are not drying in the bathroom, then the humidity in the apartment will be much lower than, for example, after a “change” at the stove.
Don’t want to take on the responsibility of being responsible for fresh air in your home? If you have ROTO fittings in your metal-plastic windows, you can leave the windows in micro-ventilation mode - the heat will not leave the apartment, and fresh air will seep in gradually but constantly. All you need to do is turn the sash handle 75 degrees. A small gap will relieve condensation from the glass, take care of maintaining the temperature in the room at a healthy 21-23 degrees, and prevent mold from growing on the surface of the window slopes.
Reason for fogging
Are the windows “crying”?
This phenomenon is faced not only by owners of budget double-glazed windows, but also of luxury designs.
Some correctly define this phenomenon as condensation, while others mistakenly claim that the windows in their apartment have begun to sweat. However, the first definition is correct, and I will tell you why and how condensation forms on windows.
The most common cases of window fogging:
- only in the morning, somewhere between 8 and 10;
- only with the arrival of the cold season;
- only in one room, despite the fact that all rooms have structures from the same company;
- the windows sweat so much that there are puddles on the windowsill.
What does window glass with condensation look like?
In most cases, condensation appears as a cluster of droplets different sizes, appears on the entire surface of the window, but there is noticeably more moisture at the edges near the profiles. When, under the influence of gravity, the drops roll down, along the way they merge with all those they encounter into one stream. If along the route of a drop falling down it encounters many “sisters”, then a small puddle will appear on the windowsill. And how to resist such disgrace? After all, it’s not difficult to remove one puddle from the window. But the thing is, she won't be alone.
Perhaps you have already encountered fogging of windows, and even expressed complaints to the company from which you purchased double-glazed windows. Like, why did they sell me a defective product, adding a catchphrase like “the old windows didn’t sweat.”
I can assure you that sellers of double-glazed windows are to blame for fogging of the latter only in 3-5% of cases. Other incidents happen for completely different reasons.
Where does condensate come from?
Condensation is moisture from the air that has settled on some surface. That is, this is a manifestation of a change in the state of water when, under the influence of external factors, it ceases to be steam and becomes liquid. And the lower the temperature of the surface, in our case it is window glass, the greater the volume of condensate that appears on it. But the temperature difference between the air and the surface of an object is not the only factor in the formation of condensation. Due to excess moisture in the air of the room, it also falls out, reducing the transparency of the glass.
Speaking purely scientifically, this happens due to the coincidence of factors necessary for the manifestation of the dew point. How is it possible that dew is visible on the grass of the lawn here and there in the morning? Because short grass has a lower temperature than the air quickly warmed by the rising sun. And at a certain moment, the temperature difference creates favorable conditions for the precipitation of dew - converted moisture from steam in the atmospheric air.
Why condensation occurs on plastic windows in the video:
The windows in your apartment sweat in the same way.
Using a special table, which I mentioned earlier, you can calculate at what air temperature in the room near the glass, outside and in the room itself, condensation will occur on inner surface window. Use a hygrometer to determine the humidity level in a room. Sometimes such a device is sold in combination with a thermometer and a clock - very convenient, by the way.
The old windows did not sweat, but the new ones constantly reproached - this statement set the teeth on edge of all managers working on claims from clients who purchased metal-plastic windows. The secret to the absence of condensation on old-style windows lies in the lack of tightness in such structures. And the fact is that their external and internal glass is spaced at a greater distance from each other than the transparent elements in modern double-glazed windows. Therefore, the temperature of the internal glasses is higher and condensation does not collect on them. However, old windows do not protect the heat of rooms well.
Troubles usually start due to:
- one camera in a double glazed window(if this is not a heat-saving product with a protective coating on one of the glasses, then the appearance of condensation is not far off - in this case, only replacing the double-glazed window with a design with a more suitable chamber arrangement will help);
- window sill too wide a, preventing heat from the battery from getting closer to the window glass (the solution to the problem lies in replacing the window sill with a narrower one);
- room ventilation does not provide sufficient air exchange(check the permeability of ventilation grilles and passages - the former quickly become overgrown with a layer of grease and dust, the latter may be blocked by collapsed plaster or even a stuck animal or bird);
- excessive number of flowerpots with indoor plants(a lot of moisture evaporates from the surface of the foliage, so take care of upgrading the ventilation system);
- double glazed windows are modern, but not converted into winter mode (when reconfigured, the thermal insulation properties of double-glazed windows will increase - conversion to new mode will take a couple of minutes);
- rare ventilation(if the double-glazed windows do not have special elements for micro-ventilation, then do not forget to open the shutters every day for 10 minutes - when it is very cold outside, just do not open the window, but only move it a little away from the main frame);
- Not correct installation (alas, there are still technical incidents when installing window structures and slopes to them, which is why the products are not able to live up to the hopes placed on them - first you need to determine the type of error, and then eliminate the shortcomings made during installation);
- your life activity(for example, the kitchen is always humid due to systematic cooking and washing dishes - you can avoid condensation on the windows using a good ventilation system or double-glazed windows).
I hope that my descriptions of the main causes of condensation will help you solve your window fogging problems.
And, I hope, you understand that windows themselves do not emit dew - only moisture from the air can accumulate on their surface, changing the vapor state to liquid.
Reasons for fogging of plastic windows
Few owners of apartments or houses with metal-plastic windows have had the fate of observing condensation on the windows. Drops of moisture impair the visibility of windows, because of it, puddles form on the windowsill, and mold appears on window slopes. The reason for this misfortune may be unskilled installation of the window structure, unfavorable microclimate of the room and other factors that I will mention below.
No matter where this problem “grows” from, the average user of a PVC window hopes that it can be eliminated. That’s why the question so often comes up online about why windows sweat a lot and how to deal with it. Some people think that the structural manufacturers or installers are to blame for this. In fact, the latter are to blame only in 5% of all cases of window fogging.
Under what circumstances do windows sweat most often?
- with the onset of the cold season (condensation ceases to form only with the arrival of stable heat);
- the windows “cry” only in the morning;
- The only glass that gets wet is the windows in the kitchen;
- You observe the formation of condensation on the window in only one room.
And no matter how much you wipe the windows, they again lose their transparency due to condensation.
But you still need to remove moisture. Otherwise, by the time you solve the problem, there will be no frogs on the windowsill, but mold will definitely grow along the slopes.
Origin of condensate
When the glass of a window becomes cloudy due to fogging, it means that the surface of the glass is covered with condensation. It appears in cases where the warm air of the room comes into contact with window glass, the temperature of which is much lower. Increased humidity in the room also contributes to foggy windows.
When the apartments had wooden windows, almost no condensation formed on the glass. And those people who still remember what ordinary people looked like window designs, keep in mind the fact that such windows almost did not sweat. Therefore, the question of why modern double-glazed windows are inferior to old-style windows in this regard is periodically voiced.
This feature of old windows is based on the significant distance between the outer and inner glass. And since the second, internal one, heated up more strongly from room heat, almost no condensation formed on it. But when compared thermal insulation characteristics old frames are inferior to PVC structures.
Reasons for fogging of PVC windows in winter and methods of control
Glass begins to “cry” for various reasons. And only in rare cases does the problem begin because the structure is defective or the installers made a mistake when glazing the window opening.
Why do windows sweat?
- due to the installation of a thin double-glazed window with one chamber(if this product does not have glass with an energy-saving coating, then in winter it will definitely be covered with condensation - to correct the situation, it is enough to change the insert structure itself to a more efficient one);
- due to poor room ventilation(examine the condition of the ventilation grilles, ducts and clean if necessary);
- due to the excessive width of the window sill a, preventing the flow of air heated by the radiator from reaching the outer glass and drying its surface (eliminate the problem by replacing the window sill, connecting an additional radiator, or moving the existing one a little forward);
- due to the excessive number of plants in the house and on the windowsill in particular(you shouldn’t get rid of green pets to eliminate condensation, it’s better to set up a ventilation system);
- from forgetting to ventilate the room every day(even with high-quality double-glazed windows, arrange a small forced ventilation by opening the windows);
- due to errors during window installation(call a specialist who will find out where the air pressure points are and fill the “hole”).
If the problematic window is in the kitchen, then condensation is a consequence of high humidity and elevated temperature room air. If you put double-glazed window, then the window will stop “crying”.
When “tears” appear on the inner surface of the camera glass, this is a clear sign of a design defect or an installation error. Then file a claim with the company that supplied the defective product or provided would-be specialists to install a normal structure.
However, in most cases, neither the manufacturer nor the intermediary company providing window installation services is to blame for fogging of your double-glazed window.
He sweats due to insufficient ventilation of the room or due to the abundance of plants on the windowsill
I described in detail above how to solve such problems.
For an example of condensation occurring on a PVC window in the kitchen, see the video:
Today among different types PVC windows are the most popular. And this is completely understandable, because they do not require insulation in winter, periodic painting, and also perfectly protect your home from noise and dust. But with the onset of cold weather, condensation may form on plastic windows. As a result, such troubles as puddles on window sills, ice on windows, dampness in the room and even the formation of mold and fungi appear.
To prevent moisture condensing on plastic windows from disturbing comfortable living conditions, it is necessary to know the causes of this process, as well as methods for its prevention and elimination. This is what we will talk about next.
Condensation and its effect on the indoor microclimate
Condensation is the result of a violation of the optimal indoor microclimate. High humidity- This is a favorable environment for the development of fungi, mold and bacteria.
Sanitary standards and rules in paragraph No. 2.04.05-91 “Heating, ventilation and air conditioning” establish that optimal humidity air in a living room cannot exceed 30-45%, and the temperature should be 20-22 °C. These conditions are the most suitable for a person’s comfortable existence. Condensation will not form if these conditions are met. Therefore, if you find moisture accumulated on the windows, this is the first sign that the favorable atmosphere in your home has been disturbed.
Why doesn't condensation form on old wooden windows? Firstly, wooden windows have a fairly large distance between the panes in the frames, so glass standing with inside has a higher temperature than the same glass in a single-chamber plastic window. Secondly, wooden windows are not highly airtight, so there are drafts in the room where they are installed, which is similar to constant ventilation.
Plastic windows are sealed, so they do not allow drafts to pass through, causing increased humidity in the room and, as a result, condensation. The formation of condensation is a common phenomenon of water transitioning from gaseous state of aggregation into liquid, which occurs when the temperature decreases. When the temperature is high enough, water is in the air in the form of steam. As the temperature drops, moisture begins to condense on the surface that has the lowest temperature. In a living room, such a surface is windows.
In physics, there is such a thing as the “dew point” - this is the temperature level at which the air becomes oversaturated with moisture when it rises, and when it falls, it gets rid of it.
When constructing a building, the “dew point” is located either outside it or within its walls, but circumstances can always arise that shift this point inside the living space. Construction technology takes this fact into account and creates all the conditions to prevent such a shift. These conditions include:
- By placing the radiators under the windows, this creates a thermal barrier that prevents the passage of cold street air into the home.
- Installing frames closer to the inner window opening for better heating of the glass.
- Selecting the width of the window sill so that it does not create obstacles to the rise of heated air from the radiators.
Make even minor changes and the balance can be upset. Below is a table showing the air temperature directly near the double-glazed window at which condensation will form on the plastic window.
Advice ! Use a hygrometer to measure indoor humidity levels.
Causes of condensation
There may be several reasons:
Ways to eliminate condensation on plastic windows
Let's consider measures that will help get rid of condensation that appears on the windows:
Attention ! It is not necessary to change the entire structure; you can only replace the double-glazed window itself and leave the profile the same.
Replacement of a double-glazed window is carried out in just a few minutes, but this work must be carried out by a specialist. In addition, when contacting the seller of a defective double-glazed window, its replacement should be free.
