Intumescent Foam (Intufoam) Linear Gap Seal

Intufoam Linear Gap Seal | QI

QI Intufoam Linear Gap Seal is a versatile fire resistant expansion linear gap seal intended to provide a fire stop seal for linear joints or at the junction of compartment floors and walls. The compressible foam core accommodates different joint widths and a number of products are available providing different fire ratings, in different gaps and orientations.

Name: Intufoam


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Features & Benefits

  • Tested to BS EN1366-4:2006 + A1:2010 (Linear Gap Seals)
  • Lightweight and easy to handle
  • Provides various fire ratings
  • Suitable for various gaps

Product Information


QI Intufoam Linear Gap Seal is manufactured from specially treated type compressible foam, impregnated with fire retardant chemicals. The foam is then bonded to a graphite based intumescent material to form a composite seal. In the event of fire this expands to maintain the fire stop seal.

Technical Support & Guidance

Installation Details are available upon request. Technical questions should be submitted to

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Standards & Approvals

Building Regulations impose limitations on all gaps joints. QI Intufoam Linear Gap Seal has been tested to BS EN1366-4:2006 + A1:2010 in both wall and floor construction as a linear gap seal.



Performance Table

For available sizes & performances to suit your application, please contact our Technical Team at

Product Code: Suitable for Gaps: Range: Width of the seal: Floor or Wall: Integrity: Insulation:
QI25/30 10 to 25mm 15mm 30mm Floor 120 minutes 120 minutes
QI50/30 25 to 50mm 25mm 30mm Floor 60 minutes 60 minutes
QI50/45 25 to 50mm 25mm 45mm Floor 90 minutes 60 minutes
QI75/45 40 to 75mm 35mm 45mm Floor 60 minutes 30 minutes
QI25/30 10 to 25mm 15mm 30mm Wall 90 minutes 60 minutes
QI50/30 25 to 50mm 25mm 30mm Wall 60 minutes 25 minutes
QI50/45 25 to 50mm 25mm 30mm Wall 90 minutes 30 minutes
QI75/45 40 to 75mm 35mm 30mm Wall 60 minutes 30 minutes

Installation Information

The Intufoam system comprises of 1 metre lengths of a compressible foam core faced with a flexible intumescent material. Different products within the range have a different number of layers of materials. Intufoam provides a reliable, easily installed fire seal to resist the passage of fire through linear gaps between non-combustible surfaces. The product is tested as defined in the relevant test reports between concrete surfaces and its suitability for use in conjunction with other materials and in the intended application should be determined or verified by a suitably qualified fire engineer. Typical instances where the Intufoam may be considered are as follows:

  • Vertical joints in concrete walls.
  • Horizontal joints in concrete floors.
  • Head of wall to underside of a concrete floor.

Intufoam’s excellent compression and recovery allows movement within the product, the minimum and maximum gap sizes are set out in the table below. In the event of a fire, the product will react and become a carbonaceous char sealing the gap.

Installation is by hand, the 1 metre lengths are simply compressed by hand and inserted in the linear gap where they will then expand holding themselves in place. The Intufoam should be positioned with a minimum of 25mm recess from the edge of the substrate – 25mm up from the underside of the concrete floor or 25mm back from the outer face of the wall. Individual lengths should be installed with a tight butt joint, end to end. Where necessary to complete the length, Intufoam can be cut with a sharp knife or saw before inserting into the gap.

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QI Intufoam Expansion Joint Fire Seal - Technical Documentation

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