How to use foam?

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

Frozen polyurethane foam is an elastic solid material of yellowish-white color. This very light substance has excellent heat and noise insulation performance. It very quickly loses its properties under the influence of ultraviolet radiation, therefore it is used mainly in rooms.

This foam has a number of advantages, which distinguish it favorably against other materials:

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

Almost all of the above properties should be specified by the manufacturer in the relevant certificates that can be requested from the seller.

The following information should be applied on the package itself:

• expansion foam volume. It can be from 10 to 300%, but most often, in fact, the foam still turns out to be somewhat less, since this percentage is specified for ideal conditions;
• its viscosity;
• volume of the tank 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 is worth using.

All types of polyurethane insulation differ according to several criteria.

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

• Professional foam is available in special cylinders that are inserted into a plastic gun with metal clips. This gun allows you to spend polyurethane economically and in equal portions. The main thing is to thoroughly rinse the device after use, so that the remains of the substance in it are not frozen.
• Household foam packaging instead of a gun equipped with a small tube, which is worn on the lever. It is not suitable for large repairs, but it will perfectly cope with minor shortcomings.

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

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

In addition, the foam may vary by type depending on the class of flammability:

• B3 - combustible substance;
• B2 - self-extinguishing substance;
• B1 - refractory compounds.

Finally, the mounting 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 repairing a room with its own hands. Two-component foam freezes in a quarter of an hour and there is almost no time left to eliminate the drawbacks, so only experienced professional builders use it.

Most often, assembly foam is used in the process of installing windows and doors, laying electrical wiring and piping. Due to the high thermal insulation in this way, it is possible to substitute seams and grooves in cooling and heating systems, cracks in the roof, and when insulating the surface of walls, floor or ceiling. It perfectly fixes wall panels and foam plates, providing excellent waterproofing. It is applied outside of steel baths or cast iron baths,to reduce the heat transfer of the metal when filling the bath with hot water. With the help of polyurethane, you can insulate the space behind the PVC paneling. Almost half of the repair processes, it remains an indispensable material.

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

Installing a gun includes the following steps:

• To start, the foam balloon is heated in warm water to room temperature, and then vigorously shaken it for 30 seconds. This will give the polyurethane a uniform state, which will allow it to exit the cylinder smoothly and in full;
• the protective cap is removed from the top tank of the pistol, it turns with the handle down and the cylinder is screwed into it. The container is screwed in with force until a hiss appears, which means that the mixture has started to flow into the tool;
• if the gun was previously used and was not properly washed, then there will be no hiss heard and you will have to purchase a new tool;
• The system of connected elements is shaken several times, the adjustment screw is turned a quarter of a turn and, clamping the trigger, proceed to the application.

Working with such equipment does not require certain skills, but will require considerable dexterity if this happens for the first time.

The application of foam from the gun is performed as follows:

• first you need to clean the work surface from dust and dirt, then slightly wet it with a regular spray, because the foam interacts better with a wet surface;
• tool nozzle is directed to the surface;
• foam is supplied in the right quantity by gently pulling the trigger;
• to pour the composition into a vertical recess, it must be applied from the bottom up;
• wide spaces are filled with zigzag movements by no more than a third of the volume, since the foam expands greatly in air;
• It is better to supplement the site after than to cut off the excess of the frozen substance.

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

Unlike a convenient construction gun, household polyurethane foam is equipped with only a small PVC tube.that fits on the 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 amounts of work, because with it it is impossible to release the solution in equal portions. In addition, the balloon has to constantly keep the weight upside down, which is why the arm is constantly numb, so it is difficult to keep the movements smooth. If such a tube and adapter are not sold in combination with polyurethane insulation, you will have to buy them separately.

Learn more about how to use the foam, you will learn from the video.

Most often, the foam is purchased in the right amount at once 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 more to consider the following nuances in order to be able to save.

It is widely believed among buyers that professional foam with a pistol can be reused, but the household version with a flexible tube, alas, is disposable and cannot be re-applied to the surface. Indeed, most often, if you leave the cylinder on the pistol and block the trigger with the dispenser, the pistol will not allow air to enter the balloon and the composition will not harden. With the next use, it will be enough to remove the remains of the frozen foam from the nozzle and you can start working again. However, exactly the same can be achieved from household products. To do this, you need to start releasing the foam from the cylinder, but without letting it go out, bend and pull the soft tube with wire. The foam at its end will harden, but the fold will not allow air to penetrate further and spoil the entire volume of the substance.On next use, the frozen edge of the PVC tube is simply cut off and the foam is ready for use. Store in this form can not more than a few weeks.

If the shelf life of the foam, which is usually from 12 to 18 months, is exceeded by only a few days, then this foam is unlikely to be very different from the usual. If the shelf life is exceeded significantly, then the use of funds is still not recommended. Over time, the composition loses its properties and can behave unpredictably, which would entail even more waste in rework repair, which will be saved on the purchase of a new cylinder.

According to manufacturers' assurances, good quality foam, applied properly and protected from the ingress of large amounts of moisture and direct sunlight, can last up to 15 years. However, in practice it often turns out that its service life is limited to 3-4 years. To increase it, the foam must be plastered on top with a high-quality mortar, which will double its service life, after which it is necessary to remove the old layer and re-stack the new foam.

To repair with the use of polyurethane insulation did not bring unexpected trouble, you must correctly calculate the required number of cylinders and use them correctly. The most convenient way is to use professional products that include a construction gun in the kit, but for small amounts of work, household foam will cope no worse.