Selection rules
There are a few technical characteristics, which determine the properties of the foam and by which you can navigate in the sea of foams.
First of all, this is the temperature of use of the polyurethane polyurethane foam.
As foam cures due to moisture atmospheric air, then naturally, the relative humidity largely determines the quality and speed of curing. If the air is cold, then the relative humidity is minimal and the foam will not harden well. To improve the curing process of the foam when low temperatures, special additives are introduced into it, which are not needed at normal temperatures.
Therefore, polyurethane foam is produced in two types: summer and all-season. The latter in everyday life is often called<зимней>.
Summer foam can be used from + 5 ° C to + 30 ° C, and all-weather foam can also be used at negative temperatures, which is indicated by the manufacturer: in most cases, up to -10 ° C.
Another important indicator is the expansion of the foam during the cure time. This metric is called secondary expansion. This implies that the primary expansion occurs at the moment the contents leave the container, and that the further expansion that occurs during curing is secondary.
Secondary foam expansion is a very important indicator that affects the quality of the sealing seam.
The fact is that with a significant expansion of the foam, the bursting force increases, acting on building construction... This can lead to deformation. window profile or a door frame, not to mention the deformation of the slopes. In Western Europe, building codes have been adopted that limit the deflection of the window profile during installation. So, deformation (bulging) of the profile more than 1.5 mm is not allowed along either side. This leads to the fact that for the installation of windows and doors, polyurethane foam with a low secondary expansion (from 10% to 25%) is specially developed and used.
With large foam expansion, internal pores increase and heterogeneity increases internal structure assembly seam.
But on the other hand, the use of foam with a large secondary expansion allows you to save on materials.
Therefore, window installers have different approaches to the choice of foam. Many go through a series of setbacks until they make a final decision.
There are a number of applications where it is beneficial to use foam with high secondary expansion (100% -150%). This is the sealing of rigid structures that have sufficient strength (pipe leads or electric cable through walls), filling large openings in walls or sealing gaps between floors.
The above two technical parameters of the foam - type (summer or all-season) and secondary expansion - are the main ones when choosing a foam. Moreover, these indicators are usually given on the label of a spray can of polyurethane foam.
The working temperature range of the frozen foam is also indicated on the label.
You should especially pay attention to this if the maximum working temperature approaching 100 ° С
In practice, we additionally have to deal with one more indicator that is not indicated anywhere.
How to store Macroflex polyurethane foam correctly?
This is the viscosity (fluidity) of the foam, which characterizes the ability of the polyurethane foam to remain on a vertical surface, and not slide (drain) onto the floor. These properties of the foam can only be verified under real conditions.
In order to get a good quality seam, read the instructions on the foam label and follow the process instructions if possible.
Do not try to squeeze out the foam without first shaking it. Moreover, as practice shows, it is better to perform this operation harder and longer, otherwise no expansion of the foam will work. If it is indicated that the temperature of the balloon in frosty weather should be at least +5 degrees, then do not experiment, but heat the balloon in water or in a warm place in order to ensure expansion of the foam.
If the can does not indicate its working position, then always keep the can upside down. This ensures full foam recovery.
You can usually cut off excess foam one hour after application. The more fluidity of the foam, the longer the time before cutting off excess foam.
Polyurethane foam is not UV resistant, so it must be painted over or putty.
Foam is supplied in cans for a gun and in cans with a nozzle (tube). In the first case, it is often called professional, since it is very convenient for builders to use a pistol when working on large areas, as well as smoothly metering the flow of foam into the gap, which saves foam consumption.
The use of a gun allows you to leave an unfinished foam canister for a month, and then continue working again. It is not necessary to disconnect the cylinder from the gun. If the foam and the work is over, then the gun is washed with special cleaners, which are sold in cans and attached to the gun instead of foam.
With analysis Russian market of polyurethane foams you can find in the report of the Academy of Conjuncture of Industrial Markets "The market of polyurethane foams in Russia".
Sealing agents are indispensable in construction. The most popular among them are sealants and polyurethane foam. Many people still confuse these types of sealing mastic, thinking that they are the same thing. In fact, this is not the case. Polyurethane foam is not a sealant in the full sense of the word. Polyurethane foam is used to seal seams and joints with a width of 3 cm. Sealants are used to seal joints and seams no more than 3 cm
Polyurethane foam, in turn, is a stable chemical structure, with a low dead weight and high internal concentration. Polyurethane foam is on sale in metal aerosol cans... Shake well before use. One bottle gives up to 40 - 45 liters finished foam... The polyurethane foam hardens under the influence of moisture in the air. In the process of hardening, the polyurethane foam increases significantly in volume, forming a porous mass with excellent heat and sound insulating properties. Polyurethane foam is used for gluing, fixing, sealing joints, heat and sound insulation.
Polyurethane foam can be professional (pistol), semi-professional, summer, winter and all-season.
Polyurethane foam (abbreviated as MP) is sold in cylinders containing a liquid prepolymer and a propellant (propellant). When the contents "leave" the container under the influence of air humidity and surface moisture, a polymerization (solidification) reaction occurs. The end result is a fairly rigid polyurethane foam. Here are the main properties of the foam, for which builders value it so much:
- assembly (attaches, connects separate parts of the structure),
- soundproof,
- heat insulating,
- sealing.
In addition, polyurethane foam has other unconditional advantages.
First, the MP, expanding, fills all hard-to-reach cavities and joints.
Secondly, it is self-solidifying, so it is convenient and simple to work with it. For comparison: earlier, instead of foam, cement and tow was used for such work. First, they diluted the cement with water, then mixed it with tow. In short, the installation process was long, multi-stage and often ineffective. Now, one cylinder with polyurethane foam is enough to special efforts get the same result and even better.
Thirdly, MP - universal material: more than a thousand options for its use in construction and industry are now known
Another indisputable advantage of polyurethane foam: it is designed to work with all traditional building materials (wood, stone, concrete, plaster, metal, glass). The only exceptions are polyethylene, polypropylene, teflon, silicone, etc.
Application of polyurethane foam
Polyurethane foam occupied the part of the market where traditional materials reigned before its appearance - cement, cork, bitumen, tapes from mineral wool, plaster, etc. MP has established itself as a versatile insulating material that fills cracks, glues surfaces, moisture-proof, non-conductive, fireproof (this indicator depends on the flammability class of the MP). All this allows the widespread use of polyurethane foam for sealing and sound insulation, gluing materials. So let's take a closer look.
Insulation (sealing)
Filling cracks in cold rooms (insulation);
Filling cracks and gaps in roofing materials;
Filling voids around window and door frames, as well as other structures;
Gluing
Fixation of door and window blocks (and then you do not need to additionally screw or nail down with screws or nails).
Fastening insulating and insulation materials on the walls (if it is necessary to insulate the room, for example, with foam plates, the question often arises: how to glue the plates to the wall? The simplest solution is foam).
Soundproofing
MP allows you to reduce noise arising from the operation of pipelines, air conditioners or heating systems. Foam is used to seal the junction of the hoods and air conditioners, the gaps between the pipes. And since there are no cracks, then there will be no rattling and noise. The use of foam at home
Installation of window and door blocks.
Filling cracks and voids during renovation and construction in country houses and city apartments.
Wide application during indoor renovation (e.g. fixing wall panels etc.).
Foam can be used to seal cracks and holes on floating equipment (boats, rafts, etc.)
As you can see, the possibilities of the polyurethane foam are not limited. The only thing is that you need to know well how to use it correctly. And for this we advise you to carefully read the instructions for use. The final result depends on how competent your actions will be.
Mode of application.
Professional. This name is more of a household name. Manufacturers call it pistol foam. It differs only in the presence of cylinder working valves, that is, pistol foam is used with a special assembly gun. An assembly gun is a device that is put on a special cylinder valve designed specifically for it, thanks to which foam is supplied and dispensed into cavities and slots. Why is it "professional" after all? Yes, because such assembly gun costs 10, or even 15 times more expensive than the foam cylinder itself. And there is absolutely no point in acquiring it for one-time household chores. Such guns are used by professionals, namely builders and repairmen, who have to work with polyurethane foam sealants every day.
It is much more convenient to use the assembly gun due to the ergonomic handle and the dispensing trigger, in addition, the gun has a long metal barrel that allows you to work in hard-to-reach places... But taking care of the pistol requires additional costs, after each use it must be washed with a special cleaning agent, which frees the working cavities of the device from the foam that has not yet hardened in it. The cleaning agent itself is also under pressure in a bottle with special nozzles to make cleaning easier.
Semi-professional. Polyurethane foam, the use of which does not require any additional devices(assembly guns). To spray polyurethane foam, a special plastic tube with a lever (adapter) supplied with each cylinder is put on the valve. It is quite convenient and practical for a small amount of work. If you have not used up all the foam from the cylinder, then the straw can be removed, rinsed with acetone or a special cleaning agent and set aside with the unused cylinder until the next time.
Usage temperature
Summer foam. On the cans, the temperature is indicated from + 5 ° C to + 35 ° C, which means that the temperature of the treated surfaces must be within this range. But this does not in any way affect the temperature resistance of the hardened foam - both in summer and in winter, it ranges from -50 ° C to + 90 ° C.
Winter foam. The operating temperature of this foam ranges from -18 ° C (-10 ° C) to + 35 ° C. It should be noted that the volume of foam after it is sprayed and expanded (foam yield) decreases in proportion to the decrease in the ambient temperature. For example, the foam output from a 300 ml bottle at a temperature of + 20 ° C is 30 liters, at 0 ° C - about 25 liters, at -5 ° C - about 20 liters, at -10 ° C - about 15 liters.
All-season foam. It has absorbed all the best from summer and winter modifications, its special formula allows you to get a large foam yield, a fast polymerization process and work at low temperatures down to -10 ° C with an unheated cylinder. All-season foam is a novelty and therefore is not present in the assortment range of all manufacturers of polyurethane foam.
Tank capacity
Foam escapes from a cylinder designed for use with a construction gun more abundantly than from a conventional cylinder of the same volume, due to the higher pressure in the cylinder, which allows filling a large number of source material.
300 ml - foam yield up to 30 liters, which makes it possible to process one standard door frame with a gap of three to five centimeters.
500 ml - foam yield 35-40 l, under the same conditions - one and a half door frames.
750 ml - foam output up to 45-50 l - two or two and a half standard door frames.
Here are some tips to help you work with foam easier and get the desired result.
Preparation for use. Since the polyurethane foam sealant in the cylinders hardens under the influence of air humidity, it is advisable to additionally moisten the surface with water before application: the expansion and speed of foam hardening (polymerization) will increase.
When working with polyurethane foam is carried out at sub-zero temperature, the treated surfaces must be cleaned of ice and frost.
Before use, the can should be shaken well for about a minute and heated (without using open fire! Flammable!) To room temperature (from + 10 ° С to + 25 ° С). These measures significantly increase the yield and density of the foam.
If you plan to process window and door frames, to prevent skewing, you need to install additional spacers in them, which should not be removed until the foam has completely hardened.
Usage. When spraying, the cylinder must be held upside down, otherwise all the air will escape and the cylinder will remain without pressure, thereby becoming unsuitable for use.
The seam is filled from bottom to top in even V-shaped movements, leaving about half of the gap volume for the foam to expand.
Cavities deeper than 50 mm are filled in several stages, waiting for each layer to dry.
It should be borne in mind: despite the fact that polyurethane foam has strong adhesive properties, it is not intended for working with polyethylene and silicone surfaces. It simply does not stick to these materials.
After application. Uncured foam can be removed from clothing and other items with acetone or a specially formulated cleaner.
The average initial drying time of the foam (you can touch it) is about 10-20 minutes. The foam finally solidifies in 4-6 hours, this time directly depends on the temperature and humidity of the surrounding air.
Excess, protruding foam fragments can be cut off with a knife.
Cured foam does not withstand exposure to sunlight, therefore, during outdoor work, after final solidification, it must be additionally protected with paint or plaster.
Additional precautions
- Uncured foam irritates the skin Airways, eyes. Therefore, during work, you must use protective gloves and goggles, with insufficient ventilation and a high concentration of vapors - a respirator. The hardened foam is not harmful to human health.
- When purchasing foam, you can stumble upon a fake. How can you avoid this? After all, polyurethane foam produced in artisanal conditions without observing necessary technologies may not live up to the label's lavish promises. Unfortunately, we constantly hear about the discovery of another warehouse of counterfeit goods. We have to admit that there is no unique, reliable way to identify a fake. All kinds of special signs and holograms are not a guarantee of quality, they are forged with great success by fraudsters, since these people learn about the mandatory presence of certain protective signs on foam cylinders much earlier than we - consumers. It remains to use general recommendations that are suitable for most consumer goods, namely:
- ask the seller to show the certificate of conformity on this item;
- look at the printing quality of the label or the quality of the image applied directly to the balloon. Since counterfeits are often produced with minimal financial costs, little importance is attached to the quality of printing. Therefore, the label (balloon with the image) looks sloppy, and often the naked eye can see the displacement of colors, due to which small text becomes indistinct;
- pay attention to the date of manufacture (usually the shelf life of the foam is one year from the date of production) - expired polyurethane foam has most likely lost all its valuable qualities.
Who produces it?
Our market is currently overflowing with all kinds of polyurethane foam, but this does not mean that all offered products are of high quality. A lot of polyurethane foam that does not meet certain requirements comes to the shelves of stores and especially markets: for example, when gases harmful to the ozone layer are used as a propellant. Or there are cases when manufacturers simply do not add polyurethane foam to cylinders.
Unfortunately, many Russian traders (fortunately, not all) put the price in the first place, and not the quality of the polyurethane foam sold. And our consumers "help" them in this. After all, an ordinary buyer has practically no idea what the foam should be (how much should be in the cylinder, what quality ...).
Today installation work with the use of foam can be performed both in summer and in winter. For this purpose, special mixtures are produced in the already familiar aerosol cans. They show all their qualities at sub-zero temperatures.
That is, frost-resistant polyurethane foam expands and polymerizes as well as summer foam.
"Winter" sealant is an easy-to-use material. But it is worth knowing certain rules when using it in winter. The same packaging under different conditions gives a different yield of polyurethane foam. And this difference can affect the cost of work and the final result.
Features of the use of 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 a "summer" sealant at temperatures below +5 degrees, then 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 be drawn in, shrink. At subzero temperatures and low humidity of winter air, the viscosity of the material increases.
2. Then the "winter" foam starts to grow anyway. But this process is slow. Since at negative temperatures, the pressure in the foam cells decreases, and chemical reactions slow down.
3. While the frost-resistant foam is increasing, it must not be subjected to mechanical stress. During this period, the material is very fragile. The casing may crack and the foam will lose all its qualities. The fragility period lasts from three to six hours.
Application conditions (frost, low humidity) reduce the volume of the 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, she has nothing to absorb, since the air humidity is lowered. Therefore, it is recommended to humidify the air in the room. For these purposes, you can put a bowl of water on the heater.
Some rules for using frost-resistant polyurethane foam:
1. Optimum 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 entire mixture. When the aerosol can is horizontal, foam can clog the valve.
3. Shake the can well. The heavier it is, the longer it takes to shake. In expensive foams there is more inside polyurethane base, and less gases. There is also little free space. It takes longer to mix the foam components.
4. Moistening the surface to be treated, and then the applied foam, do not allow the accumulation of water. It can quickly turn to ice, which negatively affects the quality of the assembly sealant.
5. If the size of the gap is more than five centimeters, then it is recommended to close it from the street with cardboard or foam.
6. You can cut off the surplus of frozen foam no earlier than twenty-four hours.
Causes of trouble with frost-resistant foam
Compliance with the terms of use of "winter" foam guarantees quality insulating material... But sometimes during work the mixture is slow 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.
Household polyurethane foam with an applicator tube: Foam Premium (Penosil) summer (pack of 750 ml - 262 rubles). Photo: Penosil
Polyurethane foam is an indispensable element of many construction work. It is used for doors, filling various openings and openings, for connecting and sealing structures, fixing wall panels and roofing slate. Among the main manufacturers of these products are Henkel (Makroflex trademark), Bison International, Den Braven, Penosil, Profflex (Profflex, Storm Gun trademarks), Soudal, Selena (Tytan Professional trademark). The price of a cylinder with polyurethane foam depends on its volume, weight, brand popularity and ranges from 100 to 600 rubles. It should be noted that polyurethane foams are divided into one- and two-component. Since most of the foams on our market are single-component, let's talk about them.
The consequence of poor sealing is distortions, sagging, shortening of the service life of the windows. Correct application foam provides the required heat and sound insulation. Photo: ShutterStock / Fotodom.ru
What is polyurethane foam?
Maxi (Profflex) all-weather (pack 750 ml - 218 rubles). Photo: Profflex
One-component polyurethane foam is an aerosolized polyurethane sealant. The base of the foam is a prepolymer (prepolymer) synthesized from polyol and isocyanate. As a result of the polymerization reaction, partly taking place inside the cylinder, and mainly in air, after being released outside, these substances form polyurethane. Coming out of the balloon, the prepolymer sharply increases in volume (20–40 times) and turns into foam. Expanding, it penetrates into hard-to-reach cavities, fills the voids. Then the cellular mass gradually polymerizes (hardens), absorbing moisture from the air or from a pre-moistened surface. After a day, it becomes a chemically stable substance - polyurethane. It is non-toxic, does not deteriorate for a long time, and is resistant to moisture. This rather rigid, finely porous material consists of closed cells and serves as a good insulator.
How does household foam differ from professional foam?
Tytan Professional STD (Selena) summer (pack 750 ml - 315 rubles). Photo: Selena
The household foam cylinder is equipped with a special applicator tube. Thanks to this device, a viscous mixture is not required additional tool... Household foams are generally disposable products. The mass yield is difficult to dose, and it itself is distinguished by its high density and low polymerization rate. Professional foams are designed for repeated use and better sealing. In them, the supply and metering of the foam stream occurs with a plunger pistol. It is screwed onto a special ring on the cylinder. It is professional foam that should be preferred when installing doors and windows.
At what temperature can the foam be used?
Soft foam cleaners: PU Foam Cleaner Click (Soudal) (pack of 500 ml - 257 rubles). Photo: Soudal
Depending on the range of operating temperatures, polyurethane foams are divided into summer, winter, all-season. For the first, the range of permissible temperatures is in the zone positive values: 5 to 30 ˚C. Winter and all-season foams are used in a wider range: from –10 ° С (some from –25 ° С) to 30 ° С. In this case, it is worth considering the manufacturer's advice on the temperature of the cylinder. In the cold season with low air humidity, the course of chemical reactions slows down, the viscosity of the mixture increases, and the pressure in the cells of the foamy mass decreases. Many manufacturers for normal work it is advised to warm the balloon to room temperature (23 ° C) by keeping it in a living room for about a day or by immersing it in warm water (about 30 ° C). However, there are products for which the use of a cold bottle is acceptable.
Winter foams contain components that help to better absorb moisture from environment and maintain the desired consistency at low temperatures. Winter foams can be used in cold and warm seasons without any deterioration in performance. Photo: ShutterStock / Fotodom.ru
Why do you need to shake a can of polyurethane foam before work?
ECO Tytan Professional (Selena) (pack of 500 ml - 235 rubles). Photo: Selena
A container with polyurethane foam contains several components of different densities. When stored for a long time, they can be distributed in layers. Therefore, before starting the process, the container should be shaken vigorously for half a minute to mix the components. Also, shake it periodically during use and especially after smoke breaks. Insufficient shaking can result in a coarse foam structure and reduced foam volume. During operation, the cylinder is held upside down. In this position, the propellant gas sinks below the polymer mass and maximizes the use of the contents.
The surfaces on which the polyurethane foam is applied must be thoroughly dust-free, free from dirt, oils, grease and ice. Photo: ShutterStock / Fotodom.ru
How much foam is needed to fill the cavities?
Solid foam cleaner: Tytan Professional (Selena) (pack of 100 ml - 379 rubles). Photo: Selena
In order to prevent the deformation of insufficiently strong walls during the expansion of the foamy mass, it is recommended to fill the voids and cracks with foam by no more than a third. If desired, use multiple spacers to secure the box. Then the expanding foam will not be able to deform it. However, with the correct professional dosage of foam, this is not necessary.
The volume of the finished foam depends on the capacity of the cylinder and its filling, the temperature of the air and the cylinder, the humidity of the air, the quality of the gun and the qualifications of the master. High-performance foams yield 65 liters or more, and regular foams - 25–45 liters.
Do the surfaces wet before applying the foam?
A relative humidity of more than 50% is sufficient for the normal foam polymerization process. In such conditions, it is not necessary to moisten the surfaces. However, at low humidity (less than 50%), which is typical for the cold season and hot summer days, moistening the joints and cavities will increase adhesion and improve foam hardening. This should be done without fanaticism, so that there are no drops on the surface and no water accumulates, otherwise its excess will prevent the foam from connecting to the surface.
The construction gun must be cleaned of foam immediately after removing the empty cylinder, avoiding hardening of the mass inside the gun. Photo: ShutterStock / Fotodom.ru
When can excess foam be cut?
The polymerization time of the polyurethane foam is influenced by the temperature of the environment, the cylinder itself and the size of the cavity. On average, professional foam in a cavity 30 mm wide hardens in 20–30 minutes, and household foam is somewhat slower - in 40–60 minutes. The expansion process ends in a day, and then you can begin to remove the solid mass.
Polyurethane foam cleaners
Winter professional polyurethane foams: Makroflex Premium Mega 70 (Henkel) (pack of 870 ml - 390 rubles). Photo: Henkel
The mounting foam remaining after mechanical cleaning gun, cylinder (valve and directly outside the cylinder itself), clothing and other surfaces, can be easily removed with a special aerosol cleaner. There are two types of cleaners:
- for soft foam;
- for hardened foam.
How to store and reuse a foam canister?
Soudafoam Maxi 70 (Soudal) (pack of 870 ml - 336 rubles). Photo: Soudal
Interrupting work with household polyurethane foam, the cylinder of which is equipped with an applicator tube, can only be a short time, no more than half an hour. The mixture dries quickly in air and is able to block the release of the remaining foam. When using professional foam, manufacturers recommend not removing the gun from the cylinder until it runs out of contents. During storage, the pistol trigger is locked with a metering screw.
In this state, the cylinder with the pistol can be kept for 1-2 weeks. But its prolonged stay in warm and humid conditions significantly reduces the shelf life of the polyurethane foam. But a dry and cool room is ideal for storing a cylinder. Moreover, they install it vertically, with the valve up, since the horizontal position leads to valve malfunction.
Does the foam need to be protected from sunlight?
Tytan Professional ICE 65 (Selena) (pack of 870 ml - 340 rubles). Photo: Selena
Polyurethane foams are very sensitive to UV rays. The solidified mass darkens and crumbles under the influence of sunlight. The foam must be protected from light by plaster, panels, etc. In addition, the solidified mass does not tolerate temperatures above 110 ° C, the effects of alkalis, acids and compounds used to remove foam residues.
Foam Adhesives
GoldGun 65 (Penosil) (pack of 875 ml - 345 rubles). Photo: Penosil
The scope of application of polyurethane foam is expanding. Many manufacturers, including TECHNONICOL Corporation, Henkel, Selena, offer glue-foams for fixing thermal insulation boards from polystyrene, extruded and extruded polystyrene foam, when arranging systems on surfaces made of concrete, brick, plastered, etc. In addition, foam glue is used in the construction of walls and partitions from. Unlike conventional foams, adhesive foams are characterized by higher adhesion and low expansion rates.
Professional polyurethane foams: all-season Construction 70 (Penosil), application temperature from –10 to 30˚С (pack of 870 ml - 336 rubles). Photo: Penosil
Summer Soudafoam Professional 60 (Soudal) (unit of 750 ml - 390 rubles). Photo: Soudal
Summer Tytan Professional Gun (Selena) (pack 750 ml - 343 rubles). Photo: Selena
Polyurethane foam or spray polyurethane insulation is considered one of the most popular ways to seal seams and connectors. Builders and finishers often use it for renovations, noting its convenience and ease of use. But when choosing a material, it is necessary to take into account weather conditions, season and other factors that can affect the quality of installation. In the cold season, it is better to use special foam for work at sub-zero temperatures.
Peculiarities
From characteristics building materials the quality of the master's work directly depends. A few years ago when installing plastic windows and outside doors, builders actively closed the cracks with summer polyurethane foam. Consumers noted that after 1–2 cold seasons, the joints began to blow out, drafts occurred, and the temperature in the room dropped. When analyzing the problem, it turned out that the sealant had lost its properties, became so porous that it could hardly hold the structure.
The reason lies in wrong selection polyurethane foam. Standard series are designed for a temperature range from -10 ° to + 30 ° C. In a harsh winter, the structure of the sealant is broken, allowing water and air to pass through. The sealant breaks down faster, therefore it requires mandatory insulation with a layer of grout, putty and paint. V winter conditions better to pick special types material adapted for more extreme conditions.
Polyurethane foam for work at subzero temperatures has a number of features:
- easily tolerates drops from -50 ° to + 80 ° С;
- does not thicken when installed in light frost;
- hardens equally quickly in cold or heat;
- has excellent thermal conductivity and sound insulation;
- allows you to save up to 10% of the heat in the room.
The advent of winter foam has made it easier for many builders. With its help, it is possible to carry out installation work in cold weather, to perform an urgent installation of a window unit at low temperatures. But the choice should be approached more carefully, study the characteristics and strictly adhere to the recommendations of experienced specialists.
Views
Polyurethane foam is a thick prepolymer based on durable polyurethane foam. Under high pressure the mass is metal cylinder with a dispenser. The main reaction occurs upon contact with air: the particles of the sealant instantly expand and take the shape necessary for the builder, increasing in volume several times at once. Working with this material is not difficult, and the fast hardening process allows you not to delay the installation of the object for several days.
Conventionally, all types of foam can be divided into household and professional. The first is different small size packaging, has simple and versatile characteristics. The cylinder is immediately equipped with a spray nozzle. Series for use by master builders are produced under a mounting gun - a small device that allows you to penetrate narrow holes, it is better to control the amount of foaming. It is simply irreplaceable when installing a window unit, assembling a balcony or other complex work.
The main types of polyurethane foam that are produced on the building materials market:
- summer, suitable for work in warm conditions from May to October;
- low-temperature, intended for installation in winter;
- all-season or universal, the operating temperature of which ranges from -10 ° to + 50 ° C.
If it is necessary to carry out installation or construction at an object with an increased fire hazard, experts recommend using high-temperature foam. It is formulated from high quality polymers that do not burn even in an open flame. This allows you to restrain the air flow in the event of a fire, ensures the stability of any structure. Such material can be used in schools, shopping malls and hospitals, to insulate saunas.
What temperature will it withstand?
Most manufacturers' instructions specify a temperature range of -18 ° C. This is a kind of border of solidification and compaction of the mass. In fact, experienced builders know that degrees directly affect not only the installation conditions. The amount of polyurethane foam released by a cylinder of the same volume directly depends on the weather conditions: at an ambient temperature of -10 ° C, the output will be 50% less than at + 20 ° C.
It is more important to understand what kind of negative temperatures winter foam can withstand. The use of specialized series is necessary if operation is expected construction site in the cold season. At correct application it tolerates frost down to -35 ° С without loss of thermal conductivity and fixing properties. Some manufacturers separately indicate the maximum degree of the surface on which the polymer is applied.
Quality material keeps its shape and is absolutely safe in conditions that threaten ignition: near fireplaces and stoves, in window openings kitchens near the stove.
Scope of application
Polyurethane foam, designed for work in the cold season, has increased adhesion. This ensures fast adhesion to the surface, excellent fixation after a few hours.
When outside and internal installation the material is used for the following purposes:
- fixing large parts window frames or door jambs;
- fastening plates for wall insulation;
- sealing gaps between seams and joints with outside building;
- closing seams in a wooden steam room instead of tow;
- thermal insulation of heating or cooling systems in a house, at a manufacturing enterprise.
Winter foam is indispensable for sealing holes in the wall when removing a pipe from a steam room or an air conditioner hose. She is not afraid of the temperature difference between the street and the room, well insulates extraneous sounds.
Often the need for such material arises in the period of late autumn and winter, when, after heavy rains, accumulated in concrete slabs moisture expands, wide cracks and faults are formed. This allows for urgent repairs and protects the home from heat loss.
On the market you can find great amount samples of winter foam for construction work. It differs not only in price, but also temperature conditions... Therefore, before buying, you should read the instructions on the cylinder, not relying on the seller's tips. Feedback from colleagues or users is a great help. Some experts recommend preheating the material slightly to ensure a more even output and a large volume.
Winter foam can be used already at + 10 ° С.
Experienced craftsmen reveal several secrets that allow you to do the job efficiently and easily.
- Be sure to shake the container with leisurely movements so that the mass is evenly distributed inside.
- To improve adhesion, the surface can be slightly moistened plain water... So the polyurethane foam will lay down more neatly and firmly connect the parts.
- If the temperature outside has dropped to + 5 ° C, the bottle is lowered into the warm water(not hot) for 10-15 minutes.
- Winter foam hardens for at least 6 hours. Experts recommend large slits to close up in several stages, applying a new layer after drying. So the seam will be perfectly sealed and will serve for many years without any complaints.
When working in the cold, only winter foam with a high degree of performance should be purchased. Even an experienced builder will not be able to calculate the volume at given levels of humidity and frost. In order not to face a shortage mounting material during the installation process, it should be purchased 20-30% more than the standard set in the estimate.