Construction foams are an exceptionally versatile group of products used in many areas of daily work. They are mainly polyurethane (PU) resin-based foams, which cure in contact with moisture when applied. They can be used as a gap-filling, adhesive sealant to fix, fill and insulate against noise, cold, and drafts because they have good insulation properties and are effective at dampening sound. Furthermore, they are also used to bond insulation panels and insulating system components on top of each other due to their excellent adhesive properties and fast curing ability.

When to Use Construction Foams

There are many reasons why such construction foams have become an indispensable part of the modern building industry. They are relatively low cost, fast, and easy to apply, then in service, they are resistant to mold, moisture, and rot, etc. They also offer many other advantages for specific applications due to their portability in canisters and their lightweight nature.

Sika's Construction Foams

Sika provides a complete range of high-quality construction foams in the Sika Boom® range, with products and systems for all different application fields. These foams are generally supplied with a ready-to-use nozzle or used with a gun in professional applications.

The Sika Boom® product range, which consists of various types of expanding and adhesive foams, is designed for durable results and easy handling.

Watch this video to get more details about the Sika Boom® product range.

Construction Foam Applications

Sika Boom Application Illustration

Filling joints around door frames

Sika Boom Application Illustration

Sealing of joints in walls that require fire protection

Sika Boom Application Illustration

Bonding of bricks for non-structural building components

Bonding insulation boards for thermal insulation 

Sika Boom Application Illustration

Mounting of door frames

Sika Boom Application Illustration

Sealing gaps around windows

Sika Boom Application Illustration

Filling around pipes and conduit penetrations

Sika Boom Application Illustration

Insulating against cold and draughts

Foam Types

Application of gap filling foam
Applying Sika Boom
Applying Sika Boom
Applying Sika Boom
Man applying fire resistant Sika foam
Application of Sika Boom Cleaner

1. Gap Filling Foams

When many trades are carrying out installation and construction works, there are almost always gaps, joints and penetrations produced - the majority of which are not subsequently visible in normal daily life, as these are filled and/or covered. Such gaps commonly exist between window or door frames and the surrounding walls, or in the areas around pipework and conduit penetrations for example. To close and fill these gaps permanently, it is important to seal them with a high-quality material that will keep the joint well-insulated, especially against acoustic or thermal transfer. Gap filling foam sealants are ideal for this purpose, as they are easy to use and can seal even the most unusually shaped gaps, joints and penetrations.

Typical Applications

Acoustic and thermal gap insulation
Fixing window and door frames
Filling and sealing around pipe and ductwork penetrations
Sealing many other gaps, voids and joints

Sika Boom®-558 Flex - Video

Out of the range of expansion foams Sika Boom®-558 Flex is a flexible PU foam, which is designed for sealing joints around window and door frames, as it has a low post expansion as well as a low curing pressure. Due to its flexibility it can withstand large movements in joints.

Application of gap filling Sika foams

2. Foam Adhesives

The modern alternatives to cement-based adhesives for thermal insulation systems are adhesive PU foams. This is because they are easy to apply, for fast and clean installation, as well as bonding to many building substrates. When using adhesive PU foams to bond insulation panels, additional mechanical fixings may no longer be necessary. For this reason, this is now their main global application, particularly in basement works, as well as for bonding on to ceilings and flat roofing.

Typical Applications

Interior and exterior bonding of insulation boards made from:
Plaster and gypsum board
XPS (extruded polystyrene)
EPS (expanded polystyrene)
Wood fiber
Fiber cement

Bonding non-load-bearing walls consisting of:
Concrete blocks
Natural stone
Aerated concrete blocks

Sika Boom®-562 Foam Fix Plus - Video

One adhesive foam is Sika Boom®-562 Foam Fix Plus, which is a gun applied polyurethane foam adhesive for bonding insulation boards above and below ground. Watch this video:

Man applying foam adhesive

3. Low Isocyanate and Isocyanate-Free Foams

Low isocyanate and isocyanate-free foams are a new type of expanding foams, developed for a safer use of chemicals by consumer as well as professional users. Such products contain hardly any isocyanates or even none at all. European Parliament and Council has adopted a regulation concerning REACH to limit the use of isocyanates starting August 2023. However, in some EU countries with strict regulations, such products are widely used since many years.

Low isocyanates foams have the same properties as the traditional polyurethane foams and are used for similar applications. The absence of isocyanate in the isocyanate-free foams is noticeable in the performance. The main application is therefore limited to multi-purpose gap filling such as sealing around pipes or around windows and doors.

Typical Applications

Acoustic and thermal gap insulation
Fixing window and door frames
Sealing many other gaps, voids and joints

Sika Boom®-163 Evolution - Video

One example product is Sika Boom®-163 Evolution is a new generation of PU foam technology with very low content of monomeric isocyanates. Watch to learn more:

Application of low-isocyanate Sika foam

4. Rigid Foams

Rigid foams are 2C foams, so called because they are supplied with two components. Most polyurethane construction foams are supplied premixed and cure after application by reacting with atmospheric moisture. However, the 2C foams have a separate hardener component with the necessary moisture already integrated, which is mixed throughout the material immediately before or during application. The big advantage of this is very fast and controlled hardening, plus their resulting high compressive strength.

Typical Applications

Acoustic and thermal insulation
Fixing window and door frames, without additional mechanical fixings
When only very limited application time is available

Application of Sika rigid foams

5. Fire Resistant Foams

Fire resistant foams are used where a linear joint with a certain resistance to fire needs to be sealed. Here specific performance certification is usually required e.g. fire-resistance class.

Typical Applications

Sealing gaps and joints for resistance to fire   

Man applying fire resistant Sika foam

6. Accessories

Professional foams frequently need to be applied with professional equipment in order to develop their full potential (e.g. foam dispensing guns). Therefore, Sika provides these professional application guns together with a special cleaning solution to maintain them in good order.

Typical Applications

Proven quality professional guns
Foam gun cleaner to ensure and extend the performance of the professional guns

Many spraying foam cleaner on equipment

Sika’s Experts Provide Assistance to Benefit your Business

World Map

Local Contact

Contact a Sika expert near you for technical support and locally available products and systems.

Global Support

Contact Sika's global representative in case you need our support in an international project.