How to foam with polyurethane foam correctly. How to properly use polyurethane foam with a gun and a tube: instructions with video. Pros and cons of using foam as a sealing material

Almost every person has used polyurethane foam at least once - modern means for sealing, repairing, installing windows and doors, sealing cracks and joints. Using polyurethane foam is quite simple. There is a special gun for this, but sometimes it is not big renovation You can do without it in the house. But even simple work must be done correctly to achieve high quality.

Peculiarities

Huge assortment polyurethane foam in specialized retail outlets makes you think when choosing required material. Each of us wants to choose a high-quality and inexpensive composition. Currently, specialized retail outlets offer customers two varieties of this material: household and professional. Let's look at the features of each.

Household

The main distinctive features of household polyurethane foam are the volume of the cylinder. Manufacturers produce this material in small cylinders (about 800 ml). The bottle comes with a tube small size with a small section. The pressure level in household polyurethane foam cylinders is low, this is necessary in order to significantly reduce material consumption when performing repair work. To perform them using household polyurethane foam, you can use a special gun. The cylinder valve is designed to fix the tube and mounting gun.

Professional

To install doors, windows, and plumbing fixtures, they use a professional type of polyurethane foam. Manufacturers produce this material in cylinders with a capacity of more than 1.5 liters. The sealant is in a cylinder under high pressure. It is recommended to carry out work using professional sealant using a special gun. To make the use of the material most convenient, the cylinder is additionally equipped with fasteners for strong fixation inside the gun. A large amount of sealant in the cylinder is designed for large-scale work.

Sealants of these varieties have similar technical characteristics. When choosing the required material, you need to consider for what purpose the foam will be needed. In addition, the amount of work is also important.

Distinctive feature compositions is the possibility of re-application.

Operating rules

To perform high-quality repair or installation work using sealant, you need to know several rules for applying the material.

• The use of a special mounting gun guarantees a better result of the work performed.
• Nessesary to use professional option sealant having useful property: Quite low secondary expansion.
• It is recommended to carry out installation and repair work in the warm season: this will speed up the hardening process of the foam and preserve all its technical qualities.
• When performing work, it is necessary to use personal protective equipment.

• It is recommended to use sealant to seal minor cracks about 8 cm wide. If the width of the cracks exceeds this figure, it is advisable to use other materials (brick, wood, plastic).
• To seal cracks and crevices less than 1 cm wide, it is more economical and practical to use putty.
• During operation, the container with polyurethane foam must be kept upside down.
• Fill the gap with sealant to one third of the depth.
• After the sealant has hardened, you need to remove excess foam using a special knife.

• After completing all work, it is necessary to cover the hardened layer of foam with special means to protect it from exposure sun rays.
• To perform work on the ceiling, you need to use a special mounting foam: such a container with sealant can be used in any position.
• To foam deep crevices or cracks, you need to use special extension adapters.
• During operation, the foam container must be shaken and the nozzle of the mounting gun must be cleaned of excess sealant.

How to apply?

Before you start working with this sealant, you need to learn all the intricacies of its use. Otherwise, the quality of work will suffer, the consumption of sealant will increase significantly, which will lead to additional financial costs. First you need to choose the right mounting foam. The choice of material depends on the volume of work.

If you plan large-scale installation of doors, windows or plumbing, or a large volume of repair work, it is better to opt for professional polyurethane foam. The cost of materials of this kind is much higher, but the result of the work performed will pleasantly please you.

Minor repairs indoors (for example, sealing cracks) involves purchasing household sealant.

Applying sealant to the surface without a mounting gun can be done in several ways.

• For minor repairs, you can do without a gun. A special small tube is installed on the cylinder valve. Next, the renovation work begins.
• Professional foam can be applied using a tube, but this method will result in high consumption material and unnecessary financial costs.
• If it is not possible to use mounting gun when working with professional sealant, you can use two tubes different diameters. To do this, attach a tube to a cylinder with professional foam. large diameter, then a second (smaller) one is connected to this tube and carefully fixed. This method will significantly reduce material consumption and reduce financial costs.

Once you have decided on the method of applying the foam, you need to prepare the surface. In some cases, the sealant surface can become a false wall. The quality of seam sealing depends on how thoroughly the surface is prepared. The surface is thoroughly cleaned of dust and dirt. Special attention it is necessary to pay attention to the cracks that need to be foamed. Sometimes the surface needs to be degreased.

Large cracks are pre-filled with polystyrene foam. or others suitable material. Only after this can they be filled with foam. This will significantly reduce foam consumption and increase the quality of thermal insulation. Before starting work, the surface must be moistened. Excellent for these purposes simple will do spray.

Now you can start sealing. For correct execution For work, the foam should be at room temperature. Before starting the process, shake the container thoroughly. Only after this is a tube or gun attached to the cylinder. Now you can apply the composition.

If you decide to use foam without a special gun, you need to consider the disadvantages of this process.

• Due to the high pressure in the cylinder, foam consumption increases significantly (sometimes two or three times).
• The valve design of some cylinders does not provide for the use of a tube.

Carrying out sealing work using a gun saves a lot of time. Foaming the surface with polyurethane foam using a gun is not at all difficult.

It is enough to learn how to dose the foam output. In this way you can glue any objects, not forgetting about preparing the surface. Then we begin to apply the sealant. It is important to remember that you need to fill the vertical gap with sealant from the bottom, smoothly moving upward.

After finishing work, you must thoroughly clean the gun from foam using a special washing liquid. It needs to be poured into the tool. If during work a small amount of sealant gets on your hands, it must be removed with a solvent. Excess foam from contaminated areas must be removed during operation with a sponge soaked in solvent. If the sealant has hardened, you will have to remove it mechanically.

You cannot work with expired foam. The spray can must be handled carefully. You can't bring it near the fire. If the expiration date of the polyurethane foam has expired, the material loses its properties.

When choosing polyurethane foam, you need to remember that the container can only be used once. Therefore, before purchasing, you must carefully calculate the required volume. If you have any doubts about this, it is better to consult a specialist.

Take note of some useful tips.

• Before starting work, you should prepare a spray bottle to spray water on the surface before applying foam; you will need a knife to cut off excess material.
• During the work process, you will need a sponge or soft cloth soaked in acetone or solvent.
• The correct dosage of sealant will significantly reduce material consumption.

• It is more convenient to remove excess sealant from the surface after four hours after application; after complete hardening, this process will become much more difficult.
• Be sure to use personal protective equipment (respirator, goggles, gloves).
• It is necessary to ventilate the room during work.
• After completing all work, it is necessary to process the frozen foam special means for protection from sun rays. This must be done before the foam darkens.
• It is strictly forbidden to use the cylinder near an open fire.

Polyurethane foam on a polyurethane basis, indispensable for sealing cracks, holes, joints, heat and sound insulation, as well as for gluing various surfaces. It is not used when working with surfaces made of polypropylene, polyethylene, Teflon, silicone and wax. To understand how to use polyurethane foam, it is enough to understand the rules.

Assortment to choose from decent option

Two types of polyurethane foam - semi-professional (household) and professional (pistol). Depending on the temperature conditions choose winter, summer or off-season.

For a small amount of simple work, a relatively cheap household one is suitable. It is sold with plastic tube, the output volume is smaller and is intended for one-time use, since after opening the container its contents dry out within 24 hours.

Household

More expensive professional mounting mixture is sold complete with a special gun. It is designed for reusable use and precisely regulates the supplied volume of sealant.

Sealant with gun

High-quality pistols are made of metal and are completely dismountable. By rotating the adjusting screw located on the handle clockwise, the thickness of the supplied jet is reduced, and counterclockwise, it is increased.

Design of a special gun for polyurethane foam

This point is important because the optimal diameter of one applied layer after hardening is around 3 cm. If a larger space is filled, then the sealant is applied in two or three layers with breaks for each of the applied layers to dry.

They take into account the fact that professional sealant shrinks less than household sealant .

Preparatory stage

In order to use mounting sealant gave effect, carry out preliminary preparation which includes the following:

• Before applying sealant, surfaces are cleaned of dust and debris. If necessary, degrease with acetone or solvent.
• For good interaction of the sealant with the surface, the latter is moistened abundantly, but at the same time make sure that no drops of moisture form on the treated surface.
• Adapt the temperature of the cylinder to the temperature of the room in which the finishing is carried out. To speed up this process, if the balloon is brought from the cold, place it in warm water for an hour and a half.
• Before use, shake the container vigorously 20-30 times to mix the components of the sealant. Then remove the protective cap and screw the tube onto it, and if it is a professional composition, screw the cylinder to the gun. Make sure that during installation the tube or nozzle of the gun is not facing towards people nearby.
• Wear a work suit, protective gloves and goggles.

Preparing to work with polyurethane foam

When working with professional staff, which are used complete with a gun, before starting sealing, adjust the supply of sealant. The stream is adjusted during use by changing the force of pressing on the cap at the base of the tube.

Hardening occurs at temperatures from +5 to +35°C, air humidity of at least 60%. When working in the cold or in a dry space, hardening occurs in the presence of special additives in the composition. In this case, the sealant will harden at an air temperature of -10, or in conditions where air humidity reaches only 35%.

Rules and techniques for working with foam

To understand how to use foam correctly, you need to remember the rules.

The polyurethane foam is applied with measured, smooth movements from left to right and from bottom to top. The openings are not filled completely, but approximately half or one third, depending on the degree of shrinkage.

The length of one applied strip does not exceed 10 centimeters. When working, the cylinder is held vertically with the bottom up. In the case when work is performed on the ceiling, which causes difficulty in observing last rule, buy special composition, which works in any position. Another solution to this problem is to extend the nozzle of the gun or the main tube using flexible tubes so that the inverted cylinder does not rest against the ceiling during operation. If necessary, it is better to start work from the ceiling, since the pressure in the cylinder is the maximum possible.

Sealing cracks with a gun

When hardening, polyurethane foam begins to exert pressure on adjacent surfaces, which causes their deformation. Therefore, if it is necessary to fill gaps on both sides, as when installing doors and windows, the mounting mixture is used on one side. The other gap is filled with silicone compound.

When applying polyurethane foam to the surfaces to be treated, make sure that the tip of the tube or gun is always inside the foam itself. Periodically remove material adhering to the gun nozzle using a cloth soaked in acetone or solvent. At long period During operation, the container is shaken periodically. Extension adapters are used to process deep seams.

Shutdown

It is important not only to know how to use polyurethane foam, but also how to complete such work correctly. Wait until the sealant has completely hardened. This usually occurs within 6–12 hours. It is not advisable to touch the mounting mixture in this case, as this will disrupt the structure of the material. After which the excess formations are carefully cut off sharp knife or a hacksaw for metal.

Removing excess foam with a sharp knife

Although hardened polyurethane foam can withstand temperature changes from -40 to +90°C, it is sensitive to ultraviolet radiation. To neutralize this factor, the excess that is under such influence is covered with a layer of plaster, covered cement mortar, painted or sewn up with platbands.

The video demonstrates the stages of working with foam and how the gun is cleaned:

After using professional foam, clean the gun inside and out. For this purpose, a special flushing liquid is purchased along with the gun. Any remaining material that gets on your hands is washed off with a solvent. It is better to remove foam residues from surfaces immediately using a sponge soaked in solvent or acetone. If the foam has already hardened, it is removed mechanically.

When applying these simple rules, self-sealing all kinds of seams and cracks, insulating the distribution network and other things will not be difficult even for someone who has never done this before.

This sealing is effective for spaces from 1 to 8 cm, no more. Smaller cracks are sealed with ordinary putty, and for larger ones, additional static materials are laid inside the empty space - polystyrene foam, wooden blocks or brick.

In contact with

Polyurethane foam is an excellent sealant and insulation material. It is used both for the installation of such large-scale structures as doors and windows, and for repairs. minor defects. This material is used to patch various cracks and crevices, restore tightness at joints, and even make other building materials. Foamed polyurethane is quite easy to use, but you need to follow certain rules for working with it and be quite careful so that the seam is smooth and lasts a long time.

Peculiarities

Cured polyurethane foam is an elastic hard material yellowish-white color. This very light substance has excellent heat and sound insulation properties. It very quickly loses its properties under the influence of ultraviolet radiation, so it is used mainly indoors.

This type of foam has a number of advantages that make it stand out from other materials:

• increased moisture resistance, high levels of sound and heat insulation;
• low current conductivity, which allows it to be used when installing electrical networks;
• many types of foam are resistant to fire, which allows expanding the scope of its application;
• after leaving the cylinder, such foam expands in volume and fills even those microcracks into which it is impossible to insert the gun tube;
• polyurethane can be used to glue surfaces made of different materials, for example, wood or brick;
• The foam is absolutely non-toxic and resistant to chemical attack.

Almost all of the above properties must be indicated by the manufacturer in the appropriate certificates, which can be requested from the seller.

The packaging itself must contain the following information:

• foam expansion volume. It can range from 10 to 300%, but most often the actual foam is still slightly less, since this percentage is indicated for ideal conditions;
• its viscosity;
• the volume of the container itself.

Most often, all these characteristics depend on the type and purpose of the foam, so you need to know which polyurethane it is and what it should be used for.

Release form

All types of polyurethane insulation differ according to several criteria.

Depending on the method of application and form of release, they can be of two types.

• Professional foam is produced in special cylinders, which are inserted into a plastic gun with metal clamps. This gun allows you to use polyurethane economically and in equal portions. The main thing is to thoroughly rinse the device after use so that any remaining substances in it do not harden.
• Instead of a gun, household foam packages are equipped with a small tube that is placed on the lever. It is not suitable for large repairs, but it will cope well with minor defects.

Depending on what time of year and at what temperature the polyurethane will expand and harden, there are the following types polyurethane foam:

• summer – used at temperatures from +5 to +35 degrees;
• winter – used at temperatures from -18 to +35 degrees;
• universal - costs much more, but can be used all year round.

It is worth noting that the temperature ranges are not indicated for air, but for the surface on which the composition will be applied. The lower its temperature, the less expansion of the finished layer will be.

In addition, foam can vary in type depending on the flammability class:

• B3 – flammable substance;
• B2 – self-extinguishing substance;
• B1 – fire-resistant compounds.

Finally, polyurethane foams vary in composition. They can be one- or two-component. However, the latter type of foam is so difficult to handle that it is practically not used for private construction and when renovating premises with your own hands. Two-component foam hardens in a quarter of an hour and there is practically no time left to eliminate defects, so only experienced professional builders use it.

Scope of application

Most often, polyurethane foam is used in the process of installing windows and doors, laying electrical wiring and pipelines. Due to the high thermal insulation in this way, it is possible to foam seams and grooves in cooling and heating systems, cracks in the roof and when insulating the surface of walls, floors or ceilings. She attaches perfectly Wall panels and foam boards, providing excellent waterproofing. It is applied externally steel baths or cast iron baths to reduce heat transfer from the metal when filling the bath hot water. Using polyurethane, you can insulate the space behind the sheathing of PVC panels. In almost half of the repair processes it remains an indispensable material.

In order to avoid any problems with both small and major renovation own home or apartment, you need to be able to use both professional and household foam. To work correctly with the first one, you must correctly install and use a special construction gun.

Gun installation includes the following steps:

• to begin with, the foam balloon is heated in warm water to room temperature, then shake vigorously for 30 seconds. This will give the polyurethane a homogeneous state, which will allow it to come out of the cylinder smoothly and in full;
• The protective cap is removed from the upper tank of the gun, it is turned with the handle down and the cylinder is screwed into it. The container is screwed in with force until a hissing sound appears, which means that the mixture has begun to flow into the tool;
• if the gun has been previously used and has not been thoroughly washed, then the hissing will not be heard and you will have to purchase a new tool;
• The system of connected elements is shaken vigorously several more times, the adjustment screw is turned a quarter turn and, holding the trigger, they begin to apply.

Working with such equipment does not require specific skills, but it will require considerable dexterity if this is the first time.

Applying foam from a gun is performed as follows:

• first you need to clean it work surface from dust and dirt, then lightly wet it with a regular spray, since the foam interacts better with a wet surface;
• the tool nozzle is directed to the surface;
• foam is fed into the right amount smoothly pressing the trigger;
• to pour the composition into a vertical recess, it must be applied from bottom to top;
• wide spaces are filled with zigzag movements of no more than a third of the volume, since the foam expands greatly in air;
• It is better to replenish the area afterwards than to cut off excess hardened substance.

The gun barrel itself is quite long, but in order to glue the materials into hard to reach places, for example, to fill the voids between a false wall, it is worth additionally purchasing an extension hose that fits over it.

Despite the fact that the packaging most often indicates a hardening time of up to 8 hours, in fact this process can take up to half a day. After complete hardening, the excess is cut off with the usual stationery knife or a metal file.

Unlike convenient construction pistol, household polyurethane foam is equipped with just a small PVC tube that fits onto an adapter. In principle, the sequence of work itself is practically the same, however, more effort will have to be made to fill the gap of the same volume. Such a tube is convenient for small volumes of work, because with it it is impossible to release the solution in equal portions. In addition, you have to constantly hold the balloon upside down, causing your hand to constantly go numb, making it difficult to maintain smooth movements. If such a tube and adapter were not sold complete with polyurethane insulation, you will have to purchase them separately.

You will learn more about how to use polyurethane foam in the video.

Most often, polyurethane foam is purchased in the required volume for one time and after use, even if it is unfinished, is thrown away. And also it is not bought in advance, as it has a limited shelf life. It is worth considering the nuances described below in more detail in order to be able to save money.

Can it be used multiple times?

There is a widespread belief among buyers that professional foam with a gun can be reused, but household variety With flexible tube, alas, is disposable and cannot be reapplied to the surface. Indeed, most often, if you leave the cylinder on the gun and block the trigger with a dispenser, the gun will not allow air to enter the cylinder and the composition will not harden. The next time you use it, it will be enough to remove the remaining frozen foam from the nozzle and you can start working again. However, exactly the same can be achieved from household product. To do this, you need to start releasing the foam from the balloon, but without letting it come out, bend and tie the soft tube with wire. The foam at its end will harden, but the bend will not allow air to penetrate further and spoil the entire volume of the substance. The next time you use it, the cured edge of the PVC tube is simply cut off and the foam is ready for use. The container can be stored in this form for no more than a few weeks.

If a person types the query “spray foam without a gun how to use” into a search engine, then most likely he has never held a can of foam in his hands. Accordingly, this person did not have the opportunity to read the instructions printed on the cylinder. Well, let's fill this gap in the knowledge of beginners and conduct detailed instructions on the topic “How to use polyurethane foam without a gun.”

No super actions are required - everything is extremely clear, simple and understandable.

Briefing

- the area must be clean from dust, dirt and various types of contaminants.

Anything that might fall off is removed. Dust must be cleaned up. She - main enemy for adhesion of foam and surface.

— immediately before applying the foam, the area must be moistened with water. We advise you not to neglect this point and the adhesion will be simply excellent.

— if we are talking about installing windows or doors, then they need to be secured so that the foam does not deform the structure. Spacers must be installed in advance, but not after foaming - polyurethane foam is afraid of vibration until it hardens.

Polyurethane foam has unique properties. Use it without a gun or with it - in any case, you will get excellent results if the manufacturer does not let you down with quality. But sometimes it also happens that the user himself made several or even one mistake, so he will complain not about his crooked hands, but about the brand of foam. Read everything written below and try to remember - these rules, tips and recommendations will be useful to you:

Instead of a conclusion

Polyurethane foam without or with a gun - the main thing is that the rules of use are fully observed. Then the result will be wonderful. As a last resort, if you don’t know how to use it and don’t remember our recommendations and advice, carefully read the instructions on the cylinder - everything is also written there in an accessible manner.

I am glad to welcome readers of my blog! At the beginning of this summer, I decided to remove the window slopes at the dacha, remove the old foam and replace it with new one. As a result, I was convinced in practice that choosing and purchasing quality material- only half the battle. To reduce costs, you need to know how to use polyurethane foam. Before I clarified these points, a lot of the contents remained in the container, and work with it took place according to the principle of as it turns out. Do you want to use as much material as possible and seal joints efficiently? Then use my step-by-step instructions.

Throughout the entire period of use of polyurethane foam, manufacturers have improved its composition, producing universal or highly specialized mixtures in which certain properties are enhanced. Therefore modern construction market abounds different types installation sealants based on polyurethane, which are not so easy for the average person to understand. Quality installation work or the quality of seam sealing depends on the right choice type of polyurethane foam.

What is polyurethane foam and how to use it

The use of polyurethane foams is based on chemical reaction polymerization of macromolecules (prepolymers). An elementary polymerization reaction occurs during the reaction of polyesters and isocyanates, when the mixture hardens (polymerizes) within 5 minutes. If there is an excess of one component, the polymerization reaction slows down and stops. When the mixture comes into contact with water, the reaction resumes and the polyurethane polymer chains lengthen until they are completely cured.

Classic one-component polyurethane foam is a mixture in one container of excess polyesters with isocyanates, as a result of the reaction between which prepolymer macromolecules are formed. Under the influence of pumped aerosol gases After opening the valve, the prepolymers escape and react with water molecules in the atmosphere. As a result, the foamed prepolymers harden. At the same time, it stands out carbon dioxide, which forms the porous structure of the material.

Types of polyurethane foams: which ones are best to use?

Depending on the state of the components inside the can, there are two types assembly compositions based on ready-to-use polymers:

1. One-component. This type is distinguished by its ease of use, slow hardening, and the ability to reuse an incompletely used container. The shelf life is limited, since the polymerization reaction occurs inside the cylinder from the moment it is filled at the enterprise.
2. Two-component. In these cans, polyesters and isocyanates are contained in two separate reservoirs inside the aerosol container and are mixed just before leaving the can. Are different high speed polymerization. There is no need for the presence of water, but after opening the container you will have to use the contents within 5-10 minutes, depending on the air temperature. The shelf life is theoretically unlimited.

Which polyurethane foam to choose: important criteria

Professionals use large volumes of mounting sealant in their work, so spray gun cans for professional work allow you to accurately dose the foam output onto the work surface. This is how they differ from conventional cans with a polyethylene tube for household use.

In addition to prepolymers and aerosol gases (propellants), there are additives inside the can that regulate the size of bubbles and their number, the ratio of opened and intact bubbles in the foam, the degree of adhesion to the surface, accelerators or retarders of the polymerization reaction. Their combinations radically affect the properties of the foam, among which the following are important:

• output volume;
• primary and secondary expansion;
• density and porosity;
• fire resistance;
• moisture resistance;
• speed of drying, initial formation of surface film;
• operating temperature range.

The quality of polyurethane foam is determined by the balance between the number of bubbles formed, their calibration, diameter and the ratio of open and closed cavities inside the structure formed after hardening.

How to choose and correctly use polyurethane foam adjusted for conditions

Depending on the above qualities, polyurethane foams are divided according to purpose:

• Foams with large and moderate output volumes, which are selected taking into account the volume of installation work or the size of the cavity to be filled. Inflated output volumes, exceeding 70 liters from a 750 ml can, indicate a low-quality product or a dishonest manufacturer. Increasing volume is achieved by increasing the number of bubbles and their diameter, and exceeding certain limits reduces the mechanical and insulating qualities of the foam. The output volume is indicated on the can in large numbers, since these values, according to the manufacturer, should make a guaranteed impression on the buyer.
• For delicate installation finishing materials They produce cans with a low amount of aerosol gases, thereby achieving the effect of low initial expansion of the foam after leaving the can. To fill seams and seal joints with numerous internal voids, foam with a high coefficient of primary expansion is used.
• Compositions intended for use in extreme weather conditions. Moreover, winter compositions are designed to work in conditions of low atmospheric humidity, which characterizes negative temperatures.
• Depending on the content of fire retardants, conventional and fire-resistant compounds are distinguished.
• Moisture-resistant compositions are characterized by a high content of surfactants that form solid bubbles. In such foam, the number of unopened bubbles exceeds the number of opened ones (up to 90%), which prevents the absorption of moisture. Because of this structure, moisture-resistant foams are more susceptible to secondary expansion and shrinkage when ambient temperatures fluctuate.
• Foam gels and adhesives ( liquid foam) compositions for the installation of foam concrete blocks.

Many types are considered moisture resistant due to the dense surface film that forms when drying. When sealing joints and surfaces in contact with water, excess polyurethane that protrudes is not cut off so as not to damage the integrity of the film.

Properties of polyurethane foam: how to use them

The material has a number of useful qualities:

• high filling and compacting properties;
• low thermal conductivity;
• opportunity to work with different materials and their combinations (except for polyethylene);
• after hardening, polyurethane acquires mechanical strength;
• opportunity quick removal excess protruding from the cavity;
• convenient use;
• moisture resistance and sound insulation;
• after the completion of the polymerization reaction, the release of any substances into the atmosphere completely stops;
• does not collapse paint and varnish materials(with the exception of materials based on nitrocellulose);
• the ability to compensate for thermal deformations of structural elements while maintaining the integrity of the seam.

The main disadvantage of foams is considered to be sensitivity to ultraviolet radiation, from which the polymer is destroyed. This requires protection in the external joints by painting or puttying.

Scope of use of polyurethane foam

This material received wide application V different areas construction:

• installation and sealing of windows, door frames;
• filling cracks and joints load-bearing structures, sealing of roofs, openings for pipes;
• installation of panels at finishing works, installation of plumbing, foam concrete blocks;
• Due to its waterproofing properties and buoyancy, this material is used in shipbuilding.

How to use the cylinder option correctly

How to use polyurethane foam: step-by-step instructions

To avoid common mistakes when performing installation work or sealing seams, professionals recommend adhering to the following recommendations:

• Before work, surfaces are cleaned of dust, dirt and degreased. This way it is possible to achieve sufficient adhesion.
• For household types the yield is 30-45 liters, so you need to fill the seam to 30% of its volume. After expansion, the foam will fill the entire volume of space, and the amount of protruding material will be insignificant. Correct dosing will optimize material consumption and reduce the risk of contamination of adjacent surfaces.
• Winter foam has a low yield, but is characterized by a high coefficient of secondary expansion. This is explained by the rapidity of formation of the primary surface film during the long completion of complete polymerization.
• When working, keep the can upside down. Otherwise, aerosol gases will come out first, and liquid components will remain inside the container.
• To speed up polymerization, it is recommended to spray the surface with water. For the same reason, do not wipe off splashes of foam that fall on adjacent surfaces with a damp cloth. To remove contaminants, use special removers or acetone.
• When working with winter foam, before use, the container is kept at room temperature so that it warms up to 20-24 °C.
• When installing wooden door frames, compounds with small secondary expansion are used. Strong expansion will deform the box. In any case, you will have to use spacers and gaskets.
• Materials with low secondary expansion are denser and, accordingly, have high waterproofing properties. Such qualities are typical for expensive professional polyurethane foams.

Polyurethane foam has speeded up and simplified installation work in construction, which has significantly increased labor productivity.

How to use polyurethane foam correctly

Polyurethane foam today is a popular building material, with the help of which a lot of outdated products have been replaced. For example, tow, adhesives, cement mortars.

It is divided into several types. Popular - with high expansion. It is relevant in those works where maximum sealing is achieved. The gap or hole is filled with the composition from the cylinder. After a few seconds, it expands, filling the space and getting into hard-to-reach places.

An option is also available with a much lower expansion coefficient. It is relevant in work where the gap that is being filled is small, or there are connecting elements that are fragile and delicate with the possibility of damage, or where access is left.

How to choose the right polyurethane foam based on its properties

This mounting foam is used for holes with a diameter of one to 10 centimeters. Because of large quantity works where polyurethane foam is used, manufacturers produce:

• With a minimum expansion coefficient, but implying high pressure to simplify application;
• Characterized by average performance;
• And the usual, expanding one.

Depending on the type of work, one of the proposed options is purchased and applied. Expanding foam is easy to install window frames, doorways, when building partitions in the house. The average expansion coefficient is relevant for small holes, if you use the usual expanding one for them - the polyurethane foam will mostly come out of the hole without filling it.

In addition, consumption increases. When there are a lot of holes, then the consumption of expanding foam, compared to that with average indicators, is 2-3 times greater.

Types of polyurethane foam: acrylic and silicone

As such, polyurethane foam is made on two bases: acrylic and silicone.

Silicone is different high adhesion, it is convenient to work with almost all existing building materials. With the silicone version you can easily work with materials that differ smooth surface- enamel, glass, ceramic products.

In addition, silicone polyurethane foam is durable and strong, it is not susceptible to deformation, mechanical or atmospheric influences.

Acrylic foam is created on the basis of resins. It does not contain any organic solvents, so this foam can be easily diluted with water.

The relevance of its use is undeniable if deep cracks or seams are filled.

This foam is distinguished by its quick drying, although this has a disadvantage - as the foam hardens, it will become less elastic than its silicone-based counterpart. In addition, the seams created with acrylic foam are rough, they need to be painted over, which silicone foam does not offer.

Acrylic foam tolerates sudden temperature changes and is more often used for indoor work.

How to choose the right polyurethane foam

When choosing foam, they determine what types of work will be performed with its help. Depending on this, one or another type is selected.

It differs in its expansion capabilities and ease of use. Simple options They mean a cylinder with a mechanism similar to that used in air fresheners - the user applies foam by pressing a button and it comes out of a small tube, which is a guide. This design is more often found on cylinders containing material with high degree extensions.

The second option involves using a special “gun”. A container is inserted into it, and the user can more conveniently apply the product to the surface or into the hole.

If the upcoming scope of work is small, the first option is suitable, if the scope of work involves the use of foam in large quantities, the second one will do.

Based on them, choose suitable option for a specific case.

It is worth remembering that if you have to work with a small space, polyurethane foam with low expansion properties is suitable. If you need to obtain tightness by filling holes of a large volume, then it makes sense to choose one that gives 50-60% expansion from the original state.

How to use a spray foam gun correctly

Foam with a low expansion coefficient is used not only for filling holes with a small volume or small diameter. There are some tricks that are applicable for a professional and a novice builder.

If there is only such foam, and a considerable volume is filled, then fill the gap or hole with small pieces of brick and finally blow it out with foam.

In addition, depending on the volume of work, purchase a special gun, along with which professional cylinders are used. They are larger in volume and provide better performance. Working with a pistol is much more convenient.

In any case, choose a material that is suitable for solving the problem. Or is it worth purchasing both types. With the help of an expanding one, blow out large spaces, and with the help of a low coefficient one, finish the job by eliminating minor errors and filling small cracks and holes.