Polyurethane foam - how to choose, how to apply correctly

Updated: 04/23/2021 15:30:07

Expert: Konstantin Borisovich Polyakov

*Review of the best according to the editors of expertology.ru. About the selection criteria. This material is subjective in nature, does not constitute advertising and does not serve as a purchase guide. Before purchasing, consultation with a specialist is required.

When performing a number of construction and repair work, such a universal sealing material as polyurethane foam is used. The product is a one-component polyurethane composition, which is under pressure in a cylinder. When exposed to air, the composition polymerizes and hardens, forming a dense porous layer of insulation. The material has good sound and heat insulation qualities, moisture resistance, low electrical conductivity and fire resistance. The weaknesses of polyurethane foam are its sensitivity to ultraviolet rays, due to which the sealant turns yellow and collapses. There is a huge assortment of polyurethane foams available in the retail chain. To make it easier for the buyer to choose the optimal composition based on price and properties, experts recommend taking several points into account.

How to choose polyurethane foam

The choice of polyurethane foam depends primarily on the conditions in which it will be sprayed and used. A universal option is suitable for household use. For fire hazardous premises, all materials used, including insulation, must be fire resistant. And to install the frame in the cold, you need to decide which winter foam for windows is best and check its operating temperature range.

When reviewing the offers of construction stores, the characteristics of the finished mass, user reviews, and the opinions of professionals were studied. When comparing materials and adding them to the TOP of the best, the following criteria were taken into account:

• Productivity and output volume;
• Ease of application;
• Operating temperature range;
• Quality of heat and sound insulation properties;
• Secondary expansion rate;
• Uniformity and density of texture;
• Value for money;
• Possibility to buy in popular stores;
• Purchasing level.

For a household user, the presence of an applicator is also important, but for professionals, the ability to use a cylinder with a gun will be more important.

What other types are there?

In addition to the basic set of installation compositions, there are foams with additional characteristics due to the additives and modifiers they contain. The following varieties exist:

• with an increased level of foaming - designed in such a way that the resulting increase in volume reaches 200% or more. Such compositions are widely used for foaming large cracks and joints in one pass, saving time and materials. After hardening, it has the same level of strength as standard modifications;
• with improved adhesion - fits well on any base, stays on the surface, connecting with the relief and, polymerizing, forms a reliable sealed joint.

You can learn more about what types of mounting foams are available by studying our company’s catalog. Materials are available for various types of work and use in different climatic conditions.

The best universal mounting foams

At home, in most cases, universal polyurethane foam is used, which can be applied to the surface both indoors and outdoors. To include products in the TOP, more than a dozen proposals were studied and the 4 best representatives of this segment were identified.

Macroflex

Macroflex from the Estonian manufacturer Henkel is one of the best all-season polyurethane foams with a one-component composition based on polyurethane foam. It combines an affordable price and good product properties, which is why it is loved by professional builders. The output is up to 65 liters of material. The hardening period is 24 hours, during which time the mass turns into a durable filler that is resistant to mechanical damage.

The cylinder is equipped with a temperature indicator showing whether the material can be applied under given conditions or not. In addition to the standard 750 ml bottle, the manufacturer offers 300 or 500 ml options for sealing small local cracks. Macroflex is sold complete with an applicator tube.

Advantages

• Easy application;
• Bonds to most surfaces;
• Fills the cavity evenly;
• Non-toxic;
• Good insulating properties.

Flaws

• Afraid of sunlight;
• The entire container must be used immediately.

The final output volume of the material depends on the conditions and technique of its application. Low humidity will not allow it to fully expand, and the incorrect position of the cylinder will reduce its capacity.

TechnoNIKOL No. 800 Master

Reviews about TechnoNIKOL polyurethane foam are mostly positive. It was developed by a Russian manufacturer for household use in various weather conditions. The temperature range that can be maintained is wide – from -10 to +35 degrees. The material is sold in 800 ml cylinders, the yield of which reaches 60 liters of finished insulating material. The tack time is only 15 minutes, and the full polymerization time is 24 hours. The mass hardens under the influence of moisture.

Advantages

• High penetrating ability;
• Uniform distribution without jerking;
• Dense, uniform texture after drying;
• Manufacturer's reputation.

Flaws

• May bubble at low temperatures.

The container must be stored exclusively vertically, otherwise the composition loses some of its properties.

Titan O2

The best universal polyurethane foam for a pistol from those presented in this rating. The one-part formula expands well when applied to a surface. It is intended for professional use. High performance (65 liters from a 750 ml bottle) is achieved thanks to the innovative formula.

The composition has a high level of adhesion to concrete, brick, glass, plaster, and wooden surfaces. The foam does not contain CFCs or HCFCs, making it environmentally friendly.

Advantages

• Economical consumption;
• Low secondary expansion;
• Does not have a pungent odor;
• High degree of sound and thermal insulation.

Flaws

• The price is above average.

Titan O2 is loved by professional builders because it speeds up the work process. Due to rapid drying, it can be cut off within 25 minutes after application.

Soudal

Professional polyurethane foam, which can be purchased at most hardware stores. It has low expansion and is suitable for thin joints where accuracy of application is especially important.

Soudal has high adhesion not only to brick or concrete, but also to metal or glazed surfaces. The tip is included, so the cylinder can be used not only with a construction gun.

Advantages

• Size stability;
• Homogeneous texture;
• Ease of application;
• Complete protective gloves.

Flaws

• Can't be washed.

Users note in reviews that they come across defective cylinders with a poorly functioning valve.

Popular manufacturing companies

Despite the variety of products offered by the market, there are not so many manufacturers of truly high-quality polyurethane foam. Unfortunately, there are many more companies producing low-quality sealants without the use of technological knowledge and equipment that meets modern standards.

High popularity

1. The Soudal company has factories in countries such as Belgium, Slovenia, and Poland. The polyurethane foam from this company has a good structure, yield volume, is durable, does not darken or crack over time.
2. Estonian manufacturer Krimelte (products of the Penosil brand) - good value for money, as well as a variety of sealant options for different occasions.
3. Trademark TITAN – from the manufacturer Orion (Spain, Türkiye, Poland). The products of this company foam well and do not have secondary expansion, but after a year they begin to deteriorate.

Average popularity

1. The moment of installation is inexpensive and high-quality products with low toxicity.
2. Ultima - has an affordable price, is easy to use, but at the same time has a low level of efficiency.
3. Axton - odorless, hardens quickly, but has poor adhesion and high porosity of the structure.

Polyurethane foam with low popularity

1. Makroflex (from the Estonian company Henkel) is inexpensive, hardens quickly, but foam consumption is uneconomical, the composition does not tolerate ultraviolet radiation, and also has a high level of expansion.
2. Greflex does a good job of sealing, but the composition often contains additional undesirable impurities.
3. Boxer is a budget polyurethane foam for home repairs, not suitable for outdoor use.

The best fire-resistant polyurethane foams

Fire-resistant qualities are especially important when applied in rooms with high temperature conditions: baths, factories, restaurants, nightclubs and other entertainment venues. Fire retardants are added to their composition, giving non-flammable properties to the entire composition. After analyzing this market segment, 3 leaders were identified that professionals prefer to buy.

NULLifire

A renowned manufacturer of fire-retardant coatings of excellent quality. Branded fire-resistant polyurethane foam can contain fire in the installation joint for up to 4 hours and prevents the spread of smoke and toxic gases. The quality of the product is confirmed by a safety certificate.

The mass is sold in 880 ml cylinders, from which 45 liters of finished insulating material are obtained. The universal valve will fit a sprayer or gun. The material can be applied at temperatures from +5 to +35 degrees. The filler can withstand full load, including joint mobility, within 24 hours.

Advantages

• Promotes good sound insulation;
• Suitable for most building surfaces;
• Loses stickiness within 10 minutes after application;
• The operating temperature limit reaches +130 degrees.

Flaws

• Destroys under UV rays;
• The price is above average.

For maximum effectiveness, it is recommended to use the foam together with the manufacturer’s sealants.

Rush Firestop Flex 65

Professional installation material with fire-resistant qualities, which can be purchased at an affordable price. It ideally fills seams of any thickness and has a low level of expansion during the hardening and expansion of the material. The aerosol form gives a uniform mass output throughout the use of the entire container.

From a 1 liter cylinder using a gun you can get up to 65 liters of insulating mass, which makes consumption extremely economical. And primary treatment is possible within 35 minutes. The composition formula is all-season.

Advantages

• Moisture resistance;
• Operating temperature – from -50 to +90 degrees;
• Affordable price;
• Good adhesion to various materials.

Flaws

• Bubble when applying a layer thicker than 5 cm;
• Short shelf life (9 months).

For best performance, the cylinder should be held strictly vertically, bottom up, and shake it from time to time. In this case, a homogeneous dense material is obtained. In cold weather the yield will be slightly less than in warm weather.

Remontix PRO 65

Good foam for the gun, corresponding to the flammability class G1 and GOST. It can resist heating for 4 hours and is suitable for use in rooms with increased fire safety requirements.

An 850 ml cylinder gives up to 65 liters of finished mass. An application applicator is included for convenient one-time use at home. When sprayed, the mass spreads evenly and expands well, making it suitable for filling large voids.

Advantages

• High-quality results in any weather;
• Cleans well with flushing liquid;
• Durability;
• Hardens quickly.

Flaws

• High price.

The material has problems with adhesion to polymer coatings. Before application, they must be thoroughly cleaned and the air should not be too dry.

The problem of choice and secrets of use

Coming to a building materials store, any non-professional will be confused: the market offers the buyer polyurethane foams with a significant variation in both price and quality. How to make a choice?

First of all, you need to know for what kind of work the foam will be used. It is preferable to fill narrow spaces with foam without too significant expansion; for wide cavities, strength will be important, without which it is impossible to hold the structure. In the second case, however, you can use a trick and fill the space with wood, brick or crushed stone, and only then use foam with a slight expansion.

The shelf life of the product is also important. It rarely exceeds 18 months. An expired product will most likely not have the declared properties. The “older” the cylinder, the more viscous the composition is inside it. This can be used if dense foam with small cells is more suitable for your needs. In any case, an expired cylinder should not only be used, but also stored at home; It is better to dispose of them at special collection points for such containers. It is strictly forbidden to throw cylinders, even fully used ones, into fire.

Over time, the composition may “disperse”: heavier components will sink to the bottom of the cylinder, while lighter components will rise. To ensure that the foam is homogeneous, shake the can for about 30 seconds before use: then the components will mix again, and the resulting composition will be exactly as the manufacturers intended. It is also worth shaking the container periodically during operation, but in this case you should not reach the point of fanaticism.

The surfaces on which you plan to apply foam need pre-treatment. It was written above that foam simply will not fall on inert materials. Therefore, make sure that the area being treated is not covered with one of these substances. The surface can be damp, in some cases it is even recommended, but excess water is also harmful. In addition, when working at subzero temperatures, you need to make sure there is no ice or frost.

A container of polyurethane foam contains flammable substances, and the foam itself can ignite when brought to a certain temperature. And as we remember, the combustion products of polyurethane foam are harmful to human health. Therefore, you should be careful when working with foam, not to carry out parallel welding or other work that could cause a spark. And of course, smoking is prohibited during work.

Polyurethane foam cleaners are designed to effectively remove uncured foam stains, treat the valve and cylinder, as well as the applicator ring and gun. This is necessary to avoid problems with foam coming out of the gun.

After finishing working with foam, pay attention to the gun (in case of professional materials) or adapter (in case of using household foam). They must be washed, otherwise the composition will harden inside and reuse of the equipment will become impossible. Sometimes this requires special formulations, in which case additional information is indicated on the cylinder itself.

The best winter polyurethane foams

Winter foams are designed for sealing joints at low temperatures, which is important for outdoor construction work in cold weather. In terms of adhesive and insulating properties, they are not inferior to summer materials. We analyzed 10 winter aggregates sold in construction stores and selected the 3 best from them.

Penosil Gold Gun 65 Winter

The best polyurethane foam for winter. Its consumption is economical: from a cylinder with a volume of 875 ml, 65 liters of finished mass are obtained. Product spray temperature is from -18 to +30 degrees. It does not spread when applied either in cold or heat.

The composition has strong adhesion to almost any surface. There is no need to wet the material, since Penosil Gold Gun hardens well at any humidity. All the material comes out of the container, leaving nothing behind in the packaging.

Advantages

• Fast hardening;
• Moderate secondary expansion (15%);
• Uniform structure;
• Eco-friendly composition;
• Low cost.

Flaws

• Need a gun.

When applying the mixture in the cold, you need to take into account that the container itself must be warm.

Irfix STD Winter

Inexpensive winter polyurethane foam with application temperatures from -10 to +30. It has adhesion to all common building materials. A 750 ml cylinder produces 60 liters of finished filler. Complete hardening of the mass occurs in just 6-16 hours, depending on weather conditions. After which it becomes resistant to mechanical damage and temperature changes.

Advantages

• Complete applicator;
• Aging resistance;
• Uniform expansion;
• Low price;
• Easy to paint.

Flaws

• Afraid of sunlight.

Before use at sub-zero temperatures, the cylinder must be kept for 12 hours at a temperature of +20-25 degrees. It is recommended to apply the mixture from bottom to top, filling no more than 40% of the seam with it.

Makroflex winter Pro

The most popular option for winter. It can be applied to almost any surface at temperatures down to -10 degrees. As the mass expands, it exerts low pressure on the surrounding structure, which makes it possible to work with fragile materials such as drywall. The mass is sold in 750 ml cylinders with a yield of up to 65 liters.

Advantages

• Extended shelf life;
• Manufacturer's reputation;
• Dries quickly;
• Suitable for filling large spaces;
• Excellent insulating properties.

Flaws

• High price.

The kit does not include an application tube; the can is intended for use with a construction gun only.

"Penosil"

Also not a particularly popular brand, but very high quality. The product is dense and uniform, and practically does not produce secondary expansion or shrinkage. This is a champion among MPs in terms of output volume. Effective for internal work during fixation and installation of structures, excellent in filling cavities and seams. Virtually odorless, white in color.

Among the disadvantages: Penosil is not suitable for outdoor use: it no longer works at -4°C and +35°C. During hot weather, the sealant refuses to foam, so it simply flows out. Average price – 220 rubles.

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Product range from Sika

The Sika company offers various types of polyurethane foam in its assortment. We manufacture quality products in accordance with European standards and have been present on the market for over 100 years. If you are in doubt about which polyurethane foam to choose, just contact a company specialist. We will help you choose the right solution and also calculate the material consumption for a specific project. We offer products to legal entities; we work with individuals through the company’s dealers. Contact us to find out more.