With the onset of cold weather, periodically window slopes water vapor, water or ice particles are collected, which are signs that the installed windows, letting cold air in and heated air out, which leads to heat loss of up to 10%.
The solution to the problem may be installation window designs using winter polyurethane foam. Winter polyurethane foam has good adhesion and a wide temperature range, allowing you to continue working in harsh conditions(at temperatures down to -18 ° C).
5 rules when working with winter polyurethane foam:
1. Clean the surface from debris, dust and ice. In winter, when low temperatures, the moisture content in the air is significantly lower than in summer, therefore, to achieve best result it is necessary to moisten the surface with water from a spray bottle;
2. The foam container must be kept indoors for at least 12 hours or heated in warm water, bringing the container to room temperature;
3. Before use, be sure to shake the can for 30 seconds;
4. Winter foam, like summer foam, can be applied in several layers, with the second layer applied after polymerization of the first;
5. The applied foam must be protected from the weather - ultraviolet radiation and precipitation destroy the structure of the foam, increase its porosity, and make it brittle - ideally, have a heat shield that allows installation to be carried out more comfortably and does not cool down the room.
The main installation mistake using winter polyurethane foam is foaming the contents out of a cold and sometimes frozen cylinder. As a result of these actions, the yield and quality of the foam suffers.
To check how high-quality winter foam, such as Profflex , we decided to conduct an experiment to clearly demonstrate the results.
Stage 1- Preparation:
We froze four cylinders of high-quality winter polyurethane foam different manufacturers at a temperature of -18° C.
Stage 2- Foaming:
After 1 hour of freezing, the first foaming was carried out:
Result: the foam is slightly thick, the expansion is stronger than usual, the structure
After 2 hours of freezing, a second foaming was carried out:
Result: similar to the first.
After 2.5 hours of freezing, the third foaming was carried out:
Result: thicker foam, strong expansion, increased number of bubbles.
Conclusions:
Short-term cooling of high-quality polyurethane foam does not have a critical effect on its properties; such foam can be used without preheating. However, cooled foam at certain conditions can expand more, requiring smaller amounts of crack filling. In any case, the additional expansion of the foam is influenced by the ability of gases to dissolve in the liquid (in the prepolymer inside the cylinder), which, based on the laws of physics, is higher, the lower the temperature of the cylinder.
Therefore, before use, it is advisable to bring the container with polyurethane foam to room temperature. If you do not have such an opportunity, you should remember that long-term freezing is in any case unacceptable, short-term freezing does not lead to serious changes in properties, so transportation of polyurethane foam is possible over short distances, for example, in the trunk of a car. The specific properties of frozen or refrigerated foam will vary depending on freezing time and temperature. To avoid possible installation difficulties, we recommend warming up the foam before use.
The history of the appearance of polyurethane foam
Polyurethane foam in the form in which it is known now, it began to be widely used in the 80s of the last century. But polyurethane foam, one of the types of which is polyurethane foam, was invented much earlier, back in the 40s, by the Swiss Otto Bayer, who headed a laboratory at the Bayer chemical concern. By the way, Otto himself has no relation to Friedrich Bayer, one of the founders of the concern, he is simply a namesake.
One-component, one-and-a-half and two-component polyurethane foam
Polyurethane foam can be one-component or two-component. In one-component foam, a pre-mixed prepolymer and a propellant gas, also called propellant, are placed in a canister. When leaving the container, the prepolymer foams, begins to interact with the moisture contained in the air, and polymerizes. If there is a lack of moisture, polymerization will be difficult, and large voids may remain inside the foam mass.
One-and-a-half-component foam, often called two-component foam, is stored in a container consisting of two parts. In one part there is a prepolymer, almost the same as in one-component foam, and in the other there is a catalyst that accelerates the curing process. Products from different parts containers are mixed immediately before use. One and a half component foam has more high density Compared to single-component, less secondary expansion and lower yield. But it hardens very quickly. This type of foam is used for quick fixation of window and door blocks in openings instead of mechanical fastening. One-and-a-half-component foam is used quite rarely, since it is more expensive, has a smaller output volume and must be applied within 15 minutes after activation, otherwise it will harden in the container. In the vast majority of cases, the use of one-component foam is more economically feasible.
Two-component foam is obtained directly during application by mixing two different components using special equipment. A lot of products are produced using this technology: from mattresses and car seats to thermal insulation, shoe soles and wood substitutes.
Application area of polyurethane foam
Due to such properties of polyurethane foam as low air permeability, low thermal conductivity, ease of use, it has found its application for sealing gaps when installing windows and doors, sealing cracks, insulating openings for pipes and cables, insulating balconies and others. building structures. Today, more than 2,000 areas of application of polyurethane foam are known, ranging from construction to art. It must be clearly understood that ordinary polyurethane foam is not recommended for waterproofing, since it absorbs moisture. For waterproofing, in some cases, they can only be used special types polyurethane foam. In addition, polyurethane foam is destroyed by ultraviolet radiation, and therefore requires protection from sunlight.
The excellent adhesion of polyurethane foam to most surfaces has also found application in construction. Special products have appeared, such as adhesive foam based on polyurethane foam. They differ from conventional polyurethane foam in that they have relatively low primary and secondary expansion, but at the same time higher adhesive properties. These products are used to stick to walls. thermal insulation boards, they are used as a binder for building blocks, materials made of wood, plasterboard, and metal tiles.
Polyurethane foam output volume
Perhaps the first characteristic that end consumers pay attention to. This is really important: the more foam that comes out of the can, the more work you can do with it. And this is a direct saving of both time and money. What determines the volume of foam yield?
First of all, it depends on the amount of active substance filled into the container. The weight of the cylinder can serve as a criterion for this. You can often find that identical-looking cylinders from different manufacturers with the same declared volume of foam output differ greatly in weight. All other things being equal, more foam should come out of a heavier container than from a lighter one.
However, the volume of output depends not only on the filling of the balloon. Finished foam from different manufacturers may have various characteristics, for example, density. And it is not always possible to obtain a larger output volume from a heavier cylinder than from a lighter one. In the same way, the foam that gives more volume is not always the best in other characteristics. For example, it may have a lower density and, as a result, worse thermal insulation.
Often people who decide to independently check whether the volume of foam output corresponds to that declared by the manufacturer discover that the volume turned out to be less than expected, and rush to accuse the manufacturer of dishonesty. But often the reason lies not in the buyer’s body kit, but in the test conditions. The volume of foam output is indicated for normal conditions, which are considered to be a temperature of +23°C and a humidity of 50%. The maximum volume of foam yield can be obtained only in laboratory conditions, fully observing the testing technology used by the manufacturer. For example, in dry weather or frost, the volume of foam output may be one and a half or even two times less. As for comparisons of the output volume from different cylinders, they can only be correct if the tests of these samples are carried out under the same conditions, by one person from the same gun, and best of all simultaneously.
Primary expansion of polyurethane foam
Primary expansion is the increase in volume of liquid foam immediately after the foam exits the nozzle. The mechanism of this process is as follows. Gases and prepolymer are in a cylinder under a pressure of about six atmospheres. Before use, the container is shaken, the gases are mixed with the prepolymer and partially dissolved in it. When leaving the cylinder, the mixture experiences a sharp drop in pressure and the gas bubbles compressed inside rapidly expand, forming foam. The process is similar to how carbonated drinks froth when opening a sealed bottle. This is why it is important to thoroughly shake the container before use: if this is not done, the output will not be high-quality foam with the stated output volume.
Naturally, the amount of primary expansion very much depends on external conditions: air temperature, application method, worker qualifications.
Secondary expansion of polyurethane foam
Secondary expansion is an increase in foam volume after the end of primary expansion and before complete polymerization. It is indicated as a percentage. Secondary expansion of the foam occurs as a result of the interaction of the prepolymer with moisture. During this reaction, carbon dioxide is released, the structure is formed and the foam hardens. The amount of secondary expansion depends on the formulation used and may vary from manufacturer to manufacturer. different types foam varies from 15% to 60% for professional foam and from 200% to 300% for household foam. Secondary expansion is very important indicator, which directly affects the quality of most work performed with foam. Therefore, before starting to work with foam that is new to you, it is recommended to conduct an experiment to determine the degree of secondary expansion and take this parameter into account when working.
Expansion pressure of polyurethane foam
As the foam expands, it puts pressure on the structure. The strength of this pressure depends not only on the degree of secondary expansion, but also on other characteristics of the foam. Foams with a high degree of secondary expansion do not always exert great pressure on the structure. This can only be established experimentally and, of course, then take this parameter into account when working with a specific brand of foam. When switching to another foam, you need to keep in mind that its expansion pressure may be greater and it may deform the structure more.
Time for initial processing of polyurethane foam
This term refers to the time after which the foam hardens enough so that it can be subjected to mechanical processing: trimming off excess, preparing for painting or putty. Manufacturers indicate this parameter on the cylinder; as a rule, it is several tens of minutes. But it should be borne in mind that this period is indicated for ideal conditions. In reality it is best before machining make a test cut and make sure that the foam has hardened sufficiently.
Time for complete polymerization of polyurethane foam
The time of complete polymerization is the time during which all chemicals in the foam are completed and the foam acquires its final structure. The polymerization time depends on several parameters: the quality of the foam itself, the thickness of the seam, the amount of available moisture and temperature. The faster moisture penetrates the foam, the faster and better the polymerization process. That is why it is recommended that before applying the foam, moisten the surfaces on which it will be applied, and after application, moisten the already foamed seam again. However, excessive wetting should be avoided - the surface should be damp, but not wet. With temperature, everything is the same as in any chemical reaction - the warmer the goes faster reaction. IN normal conditions Polymerization time of polyurethane foam is about 12 hours, but in frosty or dry weather, polymerization is much slower and can take several days. As for the thickness of the seam, numerous experiments from various manufacturers show that moisture can penetrate into the hardening foam to a depth of no more than 3 cm. To layers lying deeper than 3 cm from the edge, penetration of moisture is difficult, therefore the diameter of the foam roller applied in one pass is should not exceed 6 cm. If it is thicker, there is a big risk that the middle of the roller will not polymerize - a void will form there. Such a seal will have poorer sound and heat insulation and can easily collapse. That is why large openings need to be filled with foam in layers. The second layer can be applied no earlier than a crust has formed on the first. And it is imperative to moisten the surface on which the second layer will be applied.
“Shrinkage” of polyurethane foam
During the polymerization process, carbon dioxide formed in the foam, creating inside overpressure, gradually leaves the pores and is replaced by air. Depending on the speed at which these processes occur, the foam can shrink or expand. In world practice, it is believed that fluctuations in foam dimensions of ±10% are acceptable for installation plastic windows and doors.
Storage conditions and shelf life of polyurethane foam
Cylinders with polyurethane foam must be stored in a vertical position with the valve facing up at a temperature from +5°C to +25°C. Only under these conditions does the manufacturer guarantee that the foam will retain its qualities throughout the entire shelf life indicated on the packaging. The temperature limits at which the foam must be stored may not be the same as the limits at which it can be applied. So, for example, you can work with winter foam at a cylinder temperature down to -10°C, but if you store it in the cold, it will become unusable much more ahead of schedule indicated on the cylinder. Freezing of foam is allowed, but after this, to maintain the performance characteristics of the foam, the cylinders must be properly defrosted. They need to be defrosted slowly, avoiding sudden heating.
Conditions for applying polyurethane foam
U various types Application conditions for polyurethane foam may vary; they are usually indicated on the container. For summer species foam, the air temperature usually ranges from +5°C to +35°C; the highest quality winter ones, for example, KUDO ARKTIKA NORD, can be used at air temperatures down to -25°C.
It is necessary to distinguish between the outside air temperature at which the application of polyurethane foam is allowed and the temperature of the cylinder itself. For example, KUDO ARKTIKA winter foam can be used at temperatures from -18°C to +35°C, and the temperature of the cylinder should not be lower than -10°C. This is considered very good indicator, since KUDO foams use AFC (Advanced Freeze Control) technology, which allows work to be done with a cooled cylinder. For foam that does not have such technologies, the permissible temperature of the cylinder is usually above 0°C. If the cylinder has cooled below the critical temperature, it must be warmed up by placing it in warm water. Under no circumstances should the cylinder be heated with open fire or construction hair dryer– overheating can cause the cylinder to explode. Another important nuance– there should not be too much of a difference between the temperature of the foam and the temperature of the outside air, otherwise after application the foam may simply flow in the opening. To select the optimal temperature for KUDO foam, you can use a special table.
No less an important condition For correct application polyurethane foam has sufficient humidity, usually it should be at least 50%. The foam polymerizes when it reacts with moisture, so to obtain a high-quality seam, it is recommended to always moisten the surface on which the foam will be applied before starting work, and after application, moisten the foamed seam again. If the foam is applied in several layers, each layer should be moistened.
Fire-resistant polyurethane foam
Fire-resistant polyurethane foam is used in places with increased fire safety requirements. As a rule, fire-resistant foam is pink or red in color, occasionally gray. Thanks to this, it is easy to check which foam is used in the design - fire-resistant or regular.
It is important to distinguish between fire resistance and flammability. Flammability is understood as the ability of a material to maintain combustion, and fire resistance is the ability of a material to maintain integrity (E) and heat-insulating properties (I). Fire resistance tests are carried out for joints with a depth of 100 and 200 mm and a thickness of 10 to 40 mm. The time is measured in minutes during which the material was able to maintain its integrity and thermal insulation ability when exposed to an open flame.
Fire resistance indicators of KUDO polyurethane foam
When studying the fire resistance indicators of various brands of foam, it should be borne in mind that tests can be carried out for different types of seams: homogeneous from foam and combined from foam and basalt wool. If tests are carried out for a combined seam, this must be indicated in the characteristics. Such seams almost always have higher fire resistance ratings, but this does not mean that the foam itself has a higher fire resistance. It is correct to compare only indicators for seams of the same type.
Rules for working with polyurethane foam
Since polyurethane foam sticks very well to your hands and is very difficult to remove from them, you should always use protective gloves when working with it.
Before use, the container must be shaken so that the components in it are well mixed. If this is not done, you will not be able to obtain high-quality foam at the output.
Since foam polymerizes in the presence of moisture, the surface to be treated must be moistened before applying the foam. At negative temperatures moisture may freeze on the surface. Therefore, you should moisturize small areas surfaces and immediately foam them, preventing the moisture from freezing.
When applying foam, be sure to take into account the amount of its secondary expansion and try to apply the foam so that after polymerization there is no need to trim it. The fact is that a fairly dense film is formed on the surface of the foam, which reduces the hygroscopicity of the foam. If you cut it, the foam's ability to absorb moisture will increase.
After applying the foam, the seam should be moistened again for faster and better polymerization.
Polyurethane foam is destroyed under the influence of ultraviolet radiation, so after curing, the seam must be protected with plaster or another method.
Today installation work using foam can be performed both in summer and winter. For this purpose are issued special mixtures in already familiar aerosol cans. They show all their qualities when sub-zero temperature.
That is, frost-resistant polyurethane foam expands and polymerizes in the same way as “summer” foam.
“Winter” sealant is an easy-to-use material. But know certain rules It's worth it when using it in winter. Same packaging different conditions gives different yields of polyurethane foam. And this difference can affect the cost of work and the final result.
Features of using polyurethane foam in the cold
Frost-resistant polyurethane foams behave well at temperatures down to -10 degrees (some up to -25 degrees). If you work with “summer” sealant at temperatures below +5 degrees, it will increase very slightly, and subsequently crack and crumble.
How does frost-resistant foam behave at sub-zero temperatures?
1. Immediately after application, the mixture may retract and shrink. At sub-zero temperatures and low humidity in winter air, the viscosity of the material increases.
2. Then the “winter” foam still begins to grow. But this process is going slowly. Since at negative temperatures the pressure in the foam cells decreases and chemical reactions slow down.
3. While the frost-resistant foam is increasing, mechanical impacts on it should not be allowed. During this period the material is very fragile. The shell may crack and the foam will lose all its qualities. The duration of the fragility period is from three to six hours.
Application conditions (frost, low humidity) reduce the volume of polyurethane foam and slow down the polymerization process. In practice it looks like this:
During the polymerization process, the foam actively absorbs moisture. But in winter there is not much for it to absorb, since air humidity is low. Therefore, it is recommended to humidify the air in the room. For these purposes, you can place a bowl of water on the heater.
Some rules for using frost-resistant polyurethane foam:
1. Optimal temperature surfaces where the sealant will be applied - from +10 degrees.
In cold weather, the viscosity of the foam increases. It sticks to the walls of the container - there is no way to use the whole mixture. If the aerosol package is positioned horizontally, foam may clog the valve.
3. Be sure to shake the can well. The heavier it is, the longer you need to shake it. Expensive foams contain more polyurethane base, and less gases. Accordingly, there is also little free space. To mix the foam components, you have to shake longer.
4. When moistening the surface to be treated and then the applied foam, do not allow water to accumulate. It can quickly turn into ice, which will negatively affect the quality of the installation sealant.
5. If the size of the gap is more than five centimeters, then it is recommended to cover it from the street with cardboard or foam plastic.
6. Trim off excess frozen foam no earlier than twenty-four hours later.
Causes of troubles with frost-resistant foam
Compliance with the conditions for using “winter” foam guarantees quality insulating material. But sometimes during operation the mixture flows slowly or in limited quantities. Possible reasons:
You can try to save the situation (if everything is in order with the valve). You need to release a little gas so that it breaks through the passage. And then shake the balloon for a long time and thoroughly.
Aerosol polyurethane foam insulation (PPU), or, as it is often called, polyurethane foam, has confidently entered the market building materials and is increasingly strengthening its position on it. At the moment there are quite a large number of manufacturers of polyurethane foam, producing an even larger number of different brands of this product with different properties and characteristics.
In this article we will not consider everything existing species PPU, but let's focus on one of them - this is professional polyurethane foam with an NBS adapter for a gun. If with the “summer” version everything is more or less clear, then the “winter” version, on the contrary, raises a number of questions and doubts among consumers of this product, and more specifically, among installers of translucent structures, so we chose the “winter” one for consideration in the article. polyurethane foam with an NBS adapter for the gun.
First, a little about the sad
Unfortunately, installers often do not think about what needs to be done to ensure that the polyurethane foam behaves as everyone would like when working in winter. When choosing a brand of polyurethane foam, installers are guided by their own subjective opinion and experience gained in the process of working with various brands polyurethane foam. However, it should be noted that with this approach to the issue great importance plays a moment of chance, or rather a random combination of certain factors. Influencing factors include: air temperature, surface temperature assembly seam, the temperature of the PU foam cylinder, the absolute humidity of the air and surfaces under which work is carried out, the design and quality of the dispenser gun, the thoroughness of shaking the PU foam cylinder (mixing the components) before use, the pressure and composition of the displacing gas in the cylinder, the quality of the PU foam components.
So, the installer arrived at the site, and in his arsenal there was a certain brand of polyurethane foam. For example, the combination of the above factors is successful. This brand of foam performed well under these conditions. At the next object successful combination factors everything will be fine too. Naturally, the installer will consider this brand of polyurethane foam to be good. But for some reason, a different brand of polyurethane foam was purchased for the next project and the combination of factors was also not as successful as at the previous sites, the polyurethane foam behaved worse and... immediately became “bad” in the eyes of the installers. In addition, the human factor affects in terms of a biased negative attitude towards anything new. The same PPU will turn out to be very good for some, very bad for another, and neither of these for a third. However, not everything is so bad and not everything is irreparable.
About the good
Despite the above, there is an easy way to make “bad” polyurethane foam good. The method consists in simply following the instructions and recommendations for its use. One of the points is the requirement to moisten the surfaces of the assembly seam before filling it with polyurethane foam. For clarity, we will describe in detail the experiment we conducted on the behavior of “winter” polyurethane foam with an NBS adapter for a gun in conditions that are quite harsh for polyurethane foam.
Description of the experiment
Equipment
- Freezer with stabilized parameters.
- Tytan-STD dispensing gun.
Adaptations
Plastic transparent glasses. The glasses imitate the installation seam well, since only one side is open, just like in the installation seam, where polyurethane foam is limited on three sides by the profile, the wall and vapor barrier tape and PPU receives moisture only through diffusion outside, where the PSUL tape is located. The transparency of the glasses allows you to observe the behavior of the polyurethane foam without destroying the sample.
Samples for experiment
Two brands of polyurethane foam from different manufacturers. It should be noted that for the experiment we selected famous brands polyurethane foam, which have already proven themselves well in the market. For correctness, we do not indicate brand names.
Progress of the experiment
Three glasses were prepared for each brand of foam. A small amount of water was poured into glass No. 1 (a layer of about 4 - 5 mm). At the same time, the walls of the glass remained dry. Water was sprayed into glass No. 2 from the sprayer with one press of the lever, the spray torch was directed directly into the glass. As a result, small drops of water formed on the bottom and walls of the glass over the entire surface. The temperature of the water in the cups was about 15 °C. Glass No. 3 is dry.
The glasses as a set were placed in the freezer, where they were kept for about 2 - 3 minutes. After keeping the glasses in the chamber, polyurethane foam was released into them using a dispenser gun. The container was previously thoroughly shaken and had a temperature of about 20 °C. The glasses were filled with polyurethane foam one after another, without interruption. Total time filling three glasses took about 8 - 9 (eight - nine) seconds, i.e. we can assume that they were filled almost simultaneously. The same was done for the second brand of polyurethane foam. The glasses were kept in a freezer at a temperature of minus 10 - 12 ° C and relative humidity about 58 – 62 percent within 48 hours.
Experiment results
In glasses No. 1, the polyurethane foam sank significantly. The lower region, located closer to the water, has a fairly uniform structure without large pores. As the thickness of the polyurethane foam layer increases relative to the surface of the water, the quality of the material noticeably and sharply decreases. Large pores are visible. After 48 hours, the polyurethane foam had not completely crystallized. In the center of the layer, liquid, slightly foamed polyurethane foam is clearly visible (photos 1.1 and 2.1).
In glasses No. 2 the picture is completely different. PUF crystallized in full. There was no subsidence of the upper part. There are no large shells. The structure of polyurethane foam is homogeneous (photos 2.1 and 2.2).
In glasses No. 3, the polyurethane foam has collapsed greatly, huge voids have formed in the center of the layer, the structure of the polyurethane foam in most of the sample is glassy, the material is brittle (photos 3.1 and 3.2).
photo 1.1. |
 photo 1.2. |
 photo 2.1. |
 photo 2.2. |
 photo 3.1. |
 photo 3.2. |
Additional results
After removing the glasses from freezer and holding them at room temperature(about 22 °C and humidity about 45 - 50 percent) in glasses No. 1, the non-crystallized part of the polyurethane foam continued the reaction and began to foam and expand, as a result of which it broke through the surface crust and came to the surface (photo 2.4).
Conclusions from the experiment
Aerosol polyurethane foam insulation is highly susceptible to moisture during crystallization. When working with polyurethane foam, it is necessary to moisten the surfaces of the assembly joint immediately before filling it. The influence of moisture is especially strong at low air temperatures and low absolute air humidity.
During the installation of windows in the autumn winter period, and in early spring, it is recommended to use winter foam. These polyurethane foams have high adhesive strength and good adhesion to a wide range of typical materials, used in construction, reports the WINDOWS MEDIA portal.
Freezing temperatures do not necessarily mean it is necessary to stop construction or renovation work until spring. The use of appropriate winter foam allows work to continue, and the use of a heat shield protects the room from harmful effects frosty wind, snow, rain and low temperatures.
Winter polyurethane foam to the rescue
When in winter time We systematically observe that water vapor, water or ice particles collect on window slopes; this is a sign that your window lets cold air in and heated air out. This situation is the result of improperly installed or insufficiently sealed windows, which leads to additional heat loss (about 10%).
Modern technologies make it possible not to postpone window replacement until spring, but to carry it out even in winter. One of these useful solutions is winter polyurethane foam. This type of mounting foam will allow you to work in harsh winter conditions (when temperatures reach up to -10 ° C). Already from +5 °C you should use winter foam for installing windows.
When installing windows in winter, you should pay attention Special attention on the type of foam that is used for this type of work. Using appropriate winter foam helps minimize uncontrolled air flow and helps keep your home warm.
What you should know about winter foam when installing windows yourself
Often, contrary to our expectations and plans, construction work is extended. Installing and sealing windows and doors should not be put off for a long time. In this way, it will be possible to prevent possible losses from atmospheric factors (snow drifts, access to moisture and frost).
If you decide to replace a window and you have some experience construction work– there is no need to involve a team of installers – you can install it yourself, which significantly reduces the cost of investment. When replacing windows in the cold season, winter foam should be used during the installation process. The best solution there will be low expansion foams. With their help, there is no risk of an uncontrolled increase in the volume of foam, and thus the risk of deformation of the window profile is prevented.
Before applying winter foam, it is necessary to clean the working surfaces from dust and dirt. To ensure better adhesion of the mounting foam, it is recommended to coat the surface of the base of the window opening with a deep penetration primer.
Do not forget to thoroughly shake the container for about 30 seconds before use - this will allow maximum use of the contents of the container. When applying winter foam, you should carefully fill all the gaps between the window and window opening, and remove the excess.
A problem in a private home may be the installation of hard-to-reach windows (for example, those located close to the ceiling). Most commercially available foams require the container to be positioned upside down. Therefore, when choosing a product, you should pay attention to multi-position foam, which can be used in any working position.
Winter window installation in capable hands
If you do not have experience in installing windows, you should not take risks using gun foam - it is better to use household foam or call a team of professional installers. While household foam can be used by anyone, winter spray foam is intended for professional window installers.
Gun foams are more difficult to use than household foams, so appropriate skills are required to work with them. A professional team of installers working in frosty winter conditions will use winter foam because its advantages are: resistance to low temperatures and high performance.
The use of these polyurethane foams is a guarantee of effectiveness and High Quality winter installation of windows. Additional feature winter polyurethane foams is the fact that they do not require the container to be adapted to room temperature, which means that they can be used on outdoors and indoors.
In addition, the team of professionals has a heat shield at its disposal, which makes installation more comfortable and does not cool the room too much.
The influence of low temperatures on the performance of polyurethane foam
When using polyurethane foam, it should be borne in mind that the lower the air temperature, the longer time, after which you can begin pre-treatment of the hardened foam. The temperature factor affects not only the curing time, but also the performance of the product. The lower the temperature, the lower the foam yield. Winter grades of foam should solve this problem - they provide the ability to work at temperatures of -10°C.
In winter, it is advisable to use high-performance foams, since it is impossible to accurately calculate the effect of moisture and cold on the amount of foam and the time for its processing. It is better to allow for a certain degree of excess foam consumption than to face a shortage during the installation process.
Especially at low temperatures, experts recommend leaving the applied layer of foam until it hardens completely. Failure to adhere to the recommended pre-treatment time may result in irreversible changes in structure and dimensional stability, deteriorate useful qualities polyurethane foam.
It should be noted that during work carried out in the morning or late evening in early spring or late autumn, the temperature drops significantly, so the use of winter polyurethane foam is mandatory.
WINDOWS MEDIA recommends reading: At what stage of construction should windows be installed?
Summer foam for winter window installation is a big risk
At a temperature environment Below +5 °C standard summer foams are not suitable for winter installation of windows. When using this mounting foam in winter conditions, there is a risk that the sealing layer will not harden properly, and the contents of the container may not form properly during use, that is, they may not reach the desired consistency.
What does this mean in practice? Doors and windows installed with summer foam at temperatures below +5 ° C will not be sufficiently airtight and will have to be replaced for some time. And replacing polyurethane foam is not so easy (the foam adheres tightly to the surface of window and door frames, so it is very difficult to remove). Summer polyurethane foam used during winter window installation quickly loses its properties. During the expansion process, it is more difficult to control such foam, which can lead to its “overdose”, and in practice this means that it will not insulate translucent enclosing structures well.
Winter polyurethane foams mainly differ from summer foams, first of all, chemical composition gas used as a foam carrier. This makes the product suitable for use at ambient and substrate temperatures down to -10 °C (in the case of professional gun foam -10 °C is sufficient, and for household foam - 8 °C).
Winter polyurethane foams have the same adhesion strength and ability to insulate as summer foams. At the same time, winter foams work well at positive temperatures and can be used in summer, but this pattern does not work the other way around (that is, summer foams cannot be used in winter). If after installing your windows you have unused winter foam, you won’t have to wait until next winter to use it.
Windows and doors are not all the possibilities of winter polyurethane foam
During frosts, the problem of heat loss is not only leaky windows or doors. Sometimes “gaps” form in walls and partitions made of concrete, brick, wood, metal and plasterboard. In winter, in these places, in addition to heat leakage to the outside, the likelihood of fungi and mold growing increases. Accordingly, good compaction of these zones is required. For this type of work, you should also use winter mounting foams, which adhere perfectly to smooth surfaces, painted walls, glass or PVC. Some are also mold and mildew resistant.