Joint Sealing

Click on the tool below to find out about all the multipurpose features of the new Sikaflex®-11 FC

1. The Favourite for Over 50 Years

Sikaflex®-11 FC 50 year anniversary balloon with tool shelf

Sikaflex®-11 FC has been the professionals’ favourite multi-tool for sealing and bonding in construction for over 50 years.

Sikaflex®-11 FC is sold globally in over 100 countries for projects of every size.

The new Sikaflex®-11 FC Purform® builds on this legacy and will ensure that it is continued.

2. Technology that Lasts

Worker man applying Sikaflex® joint sealant at concrete building joint

Sikaflex®-11 FC gets its versatility from the technology it’s made from: polyurethane!

Polyurethane offers the best balance of properties for general sealing and bonding in construction.

A durable strong bond or a permanent tight joint are the sum of properties such as adhesion, strength, elasticity, hydrolysis, chemical and UV resistance, tear resistance and many more.

Due to the unique microstructure of polyurethane, consisting of a polymer network with hard and soft elements, polyurethane can best meet all these requirements.

Other technologies, such as STP/MS, acrylics or silicones, may have specific advantages, but overall, for durable and long-lasting sealing and bonding, there is only one – polyurethane.

3. The Latest Generation of Polyurethane

Illustration of Sika Purform® polyurethane technology close up spirals

Sikaflex®-11 FC Purform® is made from the latest generation of polyurethane.

Purform® stands for “Pure”, “Polyurethane” and “Performance”. Purform® starts at the very roots of polyurethane and gives us the control to engineer perfect and pure pre-polymers. These new building blocks are the core of the new Sikaflex® products with ultra-low free monomer diisocyanate content.

Purform® polyurethane, through its simplicity, perfection and purity, has given our engineers the scope to develop the next generation multi-tool for sealing and bonding: Sikaflex®-11 FC Purform®.

Sikaflex®-11 FC Purform® impresses with faster curing, increased durability and less exposure to monomer diisocyanate content compared to the Sikaflex®-11 FC+ of today.

4. Trust the Technical Data

Close up of Sikaflex®  11-FC Purform® primer sample in lab testing with tool

Sikaflex®-11 FC Purform® Technical Data 

Sikaflex®-11 FC is a one-part, moisture-curing, polyurethane elastic adhesive and sealant.  

  • Skin time: 70 min. (23°C, 50% r.h.)
  • Cure rate: 3 – 4 mm in 24 hrs. (23°C, 50% r.h.)
  • Lap shear strength (23°C, steel): 0.5 MPa
  • Module strength, 100%, 23°C: 0.6 MPa
  • Elongation at break of module: 400%
  • Tear resistance: 8 N/mm (generally MS and silicones are around 4 N/mm)
  • Hardness: 32 Shore A (23°C)    


  • EN 15651-1
  • EN 15651-4
  • ISO 11600


  • Solvent free and ultra-low monomer content
  • EC1PLUS, A+, M1, etc.  

5. Wide Range of Applications

Sikaflex®-11 FC Purform® can be used across a wide variety of construction application areas, both interior and exterior.

Click on the image below to learn more about these applications.

1. Bonding light elements

Sikaflex®-11 FC Purform® has some initial hold, so that light objects such as number plates, decorative elements, signals, etc. can be bonded without temporary fixing, meaning that the adhesive will keep the object in place until cured. In the cured state, Sikaflex®-11 FC Purform® can also bond heavier objects, provided enough adhesive beads are applied.

Bonding decorative elements is much easier and safer than mechanical fixing, where even drilling holes can damage the substrate, not to mention the noise of the tool and mess of the drill dust.

2. Window connection/ perimeter joints

For a tight connection between the rough brick-cement, wood or concrete construction and window frame. All these materials have very different thermal expansion properties which can be bridged by the elastic sealant. A non-airtight and leaking connection to the building leads to energy loss and moist areas around the window on which mold can grow, for example.

Make it right, make it tight.

3. Interior sealing, crack-free

Interior connection joints can show considerable movement during construction (drying) or seasons (dry air in winter from heating allows wood to shrink, humid air in summer allows wood to swell).

Sikaflex®-11 FC Purform® is safe to use inside as it meets the highest VOC standards, such as EC1PLUS, A+, M1 etc. and has ultra-low monomer content.

4. Connection joints

It’s at the joints where your building is most vulnerable to water ingress! Only elastic sealants such as Sikaflex®-11 FC Purform® can compensate for movement and vibration, ongoing shrinking, and imperfections and roughness between the building blocks.

A joint is not a gap that somehow needs to be filled; a joint is a key element of your construction and improper waterproofing at this vulnerable point will lead to costly damage from water ingress. Make it right, make it tight.

5. Elastic window sill bonding

Elastic bonding is superior to rigid bonding or fixing in cases where the building blocks have different thermal expansion properties, the surfaces are rough, or they are exposed to water (e.g. mounting a metal window sill on a brick-cement base).

The elastic adhesive sealant Sikaflex®-11 FC Purform® will compensate for the different thermal expansions, will level the roughness as it is applied in thick beads, and seal and prevent water ingress between the building blocks. For a durable solution, choose Sikaflex®-11 FC Purform®.   

6. Sealing and bonding drainage pipes and gutters

This is an exemplary application of bonding and sealing. The adhesive holds the pipes or gutter elements together and at the same times also seals them to each other, as well as compensating for movement and damping vibrations.

Sikaflex®-11 FC Purform® is a real multi-tool for sealing and bonding.   

7. Bonding and sealing wall casing and landscaping elements

Elastic bonding is the magic word for problem-free casing. An elastic adhesive sealant such as Sikaflex®-11 FC Purform® applied in thick beads bonds the casing elements to the wall firmly and durably by compensating for roughness and thermal movement.

An elastic adhesive sealant also seals the elements, preventing water ingress between the casing and the wall and decay of the substrates from humidity.   

8. Floor joints

For waterproofing between concrete pavement saw-cut joints, movement joints or connection joints between different substrates - the sealant needs to withstand movement, weathering and mechanical and chemical impact.Floor joints are demanding and priming of the joint’s flanks are a prerequisite for durable, tight joints.

9. Bonding and sealing stair casing elements

When bonding on substrates of a similar nature with similar thermal expansion such as concrete, a tile adhesive is the common solution. However, Sikaflex®-11 FC Purform® can also do the job.

Applied as thick beads, the adhesive sealant will compensate for roughness, dampen vibrations and provide waterproofing.    

10. Concrete construction joints

Concrete slabs have limited dimensions due to shrinking and cracking issues. Therefore, there are always joints that need to be waterproofed between concrete slabs. The joint width also varies due to the thermal movement of the concrete slabs.

Therefore, only an elastic and hydrolysis resistant sealant can durably waterproof such joints. As Sikaflex® sealants are available in several colors, the joints naturally integrate into the structure.