Celotex TB4000 High Performance PIR Insulation For Overcoming Thermal Bridging 25mm

Celotex TB4000 High Performance PIR Insulation For Overcoming Thermal Bridging 25mm

Product Code INSCELOTTB4000



Celotex TB4000 High Performance PIR Insulation For Overcoming Thermal Bridging

The Celotex TB4000 range is the thinnest product manufactured by Celotex,

TB4000 is a high performance, rigid polyisocyanurate (PIR) insulation board specifically designed to address thermal bridging and reduce localised heat losses.

It can be used throughout a building project to help maintain continuity of the insulation envelope, and is suited to floor, wall and roof systems.

Specific applications include perimeter upstand insulation in ground floors and lining door and window reveals in retrofit projects.

As well as being CE-marked, Celotex TB4000 is certified by the British Board of Agrément for floors, framed walls and pitched roofs.

Manufactured in the UK, TB4000 can help you achieve reliable, long-term energy savings.

How does TB4000 perform?

The entire thickness range offers a low thermal conductivity (lambda value) of 0.022 W/mK, putting TB4000 among the best-performing widely-available insulation materials on the market.

TB4000 will contribute to the thermal performance of any element in which it is used - but the overall heat loss from a building element depends on all of the materials used and the way they’re installed.

Product benefits:

Celotex TB4000’s low emissivity aluminium foil facing can help achieve lower U-values when installed facing a clear air space within a construction.

Like all Celotex products, TB4000 is a thermal insulation solution that can that help to meet energy use and carbon dioxide emissions targets set by national building regulations.



  • Board size: 1200mm x 2400mm
  • Thickness : 25mm
  • Lambda: 0.022 W/mK
  • Facer: Low emissivity composite aluminium foil
  • Manufactured using a blowing agent with zero ozone depletion potential (ODP) and low global warming potential (GWP)

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  • Suitable applications include:
  • Ground floors - whether solid concrete, block and beam, or suspended timber joist & including where underfloor heating is used
  • Timber and steel framed walls - between the studs
  • Pitched roofs - between the rafters
  • Flat roofs - in ventilated cold roof constructions, installed from inside the building

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