PVC foam for windows: which is better

Properly selected and correctly applied polyurethane foam for windows is an important component of their quality installation. It is difficult to imagine the installation of modern window structures made of PVC without this convenient and reliable material. The novice master will have to understand the differences and features of the foam in order to choose a composition from the wide range offered by the stores.

Properties and scope of the material

Polyurethane foam is a liquid polyurethane solution pumped into a cylinder under pressure. Once in the air, it quickly hardens and simultaneously significantly increases in volume.

There are 2 types of foam expansion:

1. Primary (when the composition leaves the cylinder). Provides ease of use: free-form depressions are filled with a solution without effort.
2. Secondary Relates to the disadvantages: an increase in the volume of sealant during the final polymerization can deform the elements of the window. Therefore, it must be taken into account when carrying out work.

Completely solidified material acquires unique useful qualities:

• Low thermal conductivity is achieved due to air bubbles located in the thickness of the hardened material. If not for the price, foam could well be considered as an alternative to the usual heaters.
• The presence of air voids increases the sound insulation of the entire window structure: the vibrations transmitted to the window are damped by foam. Thus, it is in addition to the installed rubber seals, enhancing the soundproofness.
• The hardened foam does not allow electric current, has water-repellent properties, and is not susceptible to decay or mold.

• High adhesion rates make it possible to use foam as a fixing material: it reliably fastens window or door frames, as well as other elements, in place.
• Depending on the brand, the composition does not support combustion or is completely immune to fire.

Due to its special properties, the foam is ideal for both indoor and outdoor use. But, like any material, it has disadvantages:

• After solidification, the excess composition is cut off. And if the cut surface is not treated appropriately, then water will enter the open pores. Over time, this causes the destruction of the material.

• The hardened composition does not withstand the effects of ultraviolet radiation, so it must be protected from direct sunlight.
• We have to follow the rules for storing cylinders: strictly upright at a temperature range of +5 отС to +25 ˚С.

High adhesion of the foam allows it to firmly adhere to surfaces of different materials. Therefore, you should work with the composition very carefully: if you get on your hands or other parts of the body, you can wipe it off only with the upper layer of the skin, which will take at least several days. Gloves must be used when pouring. You should also reliably cover all surfaces on which the solution may drip.

If the foam does get on the floor, furniture or other surfaces, it can be removed in several ways, which are described here.

Professional or household?

According to the design features of the cylinders and other indicators, household and professional foam are distinguished.

The compositions with which the masters work are used only with a special gun. A special valve is provided for its fastening in the cylinder.

The use of this design provides the following advantages:

• Ergonomics of the gun allows the master to fill in the cracks with one hand. The second remains free, due to which it is possible to work alone at certain stages.
• The gun makes it possible to accurately dose the volume of the produced solution. This reduces consumption by reducing unnecessary losses.
• A thin long nozzle will easily deliver the solution to hard-to-reach slots and openings.
• The cylinder may be used in any position.
• A reusable valve ensures that the solution remains intact between repairs.

When choosing professional cylinders, you do not need to solve the often arising question: where to use the remaining solution with benefit?

• Professional compositions have better performance characteristics than household ones. For example, they have a lower secondary expansion coefficient, which makes their use more convenient.

Techniques for filling foam with a professional gun are shown in the following video.

Mr. Build strongly recommends: Use only professional foam for mounting plastic windows. Secondary expansion will not create unnecessary load on the structure and will not displace the frame elements. The density of the professional staff is maximum, and this will ensure the best quality of fastening, insulation and sealing of the seam.

Choose a gun by budget, ergonomics and durability. For a single procedure, the cheapest one with plastic parts is also suitable, and for professional use, give preference to collapsible high-quality models.

Household foam has less outstanding performance: worse adhesion, higher secondary expansion coefficient, lower material yield from the container. It is implemented in containers equipped with a plastic tube for supplying a solution. It is screwed onto the valve before blowing begins. It is recommended that you use up the entire bottle at once.

It is less convenient to work with household foam: both hands are used, and the spray can must be placed with the bottom up. This will provide a more complete solution yield. Use it with extreme care, in the least important places. Fill the seam no more than 50% of the depth!

Winter or summer?

Foam is divided according to the seasonality of its use. It happens:

1. Summer, suitable for operation at temperatures above +5 ˚С.
2. Winter, allowing to close up cracks at temperatures up to -18˚ С.
3. All-weather. It is found and used less often. Professionals advise using it in transition periods in the fall and winter, or dispensing with the first two varieties.

Flammability Foam

Also, the compositions differ in combustibility parameters:

• B1 - the highest fire safety class, does not ignite even in contact with an open flame.
• B2 - does not burn independently, without an additional heat source. Such compositions are called self-extinguishing.
• B3 - the lowest class of combustibility. This material is not recommended for use, especially in residential areas.

Rules for choosing foam for installing PVC windows

For high-quality installation of window blocks the composition that is most suitable for a particular case is selected. What to look for when choosing?

• The temperature at which the cracks will close up. On it choose winter, summer or all-weather foam.
• On the coefficient of secondary expansion. The lower the value, the better. It is recommended not to use formulations with an indicator greater than 15–20%. Professional foam easily fits into such a framework, but with a household choice you should carefully.
• For the expiration date. No one will predict how the behavior of the solution will change after the storage time. Better not take the risk.
• For the fullness of the cylinder. Underfilling is a frequent occurrence. It is simple to check: for this, the can is weighed. A full capacity of 750 ml weighs about 900 g.

Many problems are caused by the calculation of the required number of cylinders. It is believed that for one running meter when installing windows in a panel high-rise, 300 ml of foam will be required, for brick material the volume is 400-450 ml, for Stalin-built houses - 500 ml. But on the bottle, the manufacturer indicates the yield of the sealant under ideal conditions, in reality this cannot be achieved. Therefore, an extra cylinder in reserve will not hurt.

Rating of brands of polyurethane foam

Professionals prefer proven brands. In the Russian market, such mounting compounds have proven themselves:

1. "Moment-Installation" - foam from a domestic manufacturer. More often all-weather, it is presented in professional and household containers. Dense, uniform with good adhesion, it can be painted. The material is characterized by secondary expansion, so you need to work with it carefully, fixing the window elements with spacers.
2. Soudal - compounds with a finely porous structure without an unpleasant odor. Three modifications - summer, winter, fire resistant. Shrinkage and secondary swelling are minimal, the material is characterized by high adhesion, uniform solidification. For delicate installation work, a composition with minimal re-expansion of SOUDAFOAM GUN LOW EXPANSION is suitable.
3. Makroflex is a sealant with good adhesion and a uniform structure. With the primary expansion, it increases by 2 times, the secondary expansion is insignificant. It happens summer and earth. Cutting off the excess is allowed after 3-4 hours.
4. Penosil is a non-shrink composition with low secondary expansion and a dense, odorless structure. Gives a record high yield.
5. Tytan. It does not emit toxic fumes during operation; it has a faint odor. The expansion of the second type is practically absent. It is presented by household and professional, winter and fireproof options. Quickly freezes, surplus can be cut in an hour.

Conclusion: which foam is better for plastic windows

We sorted all the properties and parameters of the foam selection into shelves and now we will briefly and clearly answer the main question. So, for the installation of PVC windows, the professional composition of a trusted brand with minimal secondary expansion corresponding to the temperature regime is best suited.