Celotex TB4000 general application thermal bridging board Celotex Insulation

Celotex TB4000

High performance rigid Polyisocyanurate (PIR) thermal bridging insulation board.

Specifically designed to eliminate thermal bridges.

Suitable for use in a number of applications including roof, wall and floor systems.

Includes low emissivity foil facings giving improved thermal insulation performance within cavity air spaces.

Can be used to improve reliable long-term energy savings for buildings.

Thicknesses and Availability:

Available in most popular thicknesses at most depots; short lead-times may apply if we need to get stock in before delivering to site.

This TB4000 Range includes the following readily available product thicknesses: 20mm, 25mm, 30mm and 40mm.

Product Information

General information about Celotex TB4000

Product Application

Thermal bridge insulating board

Celotex's high performance polyisocyanurate (PIR) foam board, TB4000, is suitable for use in pitched and flat roofs, solid masonary walls, timber and steel framed systems, and floors.

Product Make-up


Celotex TB4000 is manufactured from rigid polyisocyanurate (PIR) using a blowing agent that has zero ozone depletion potential (zero ODP) and low global warming potential (GWP).


Faced on both sides with a low emissivity aluminium foil, autohesively bonded to the insulation core during manufacture.

Product Properties

Thickness 20mm to 40mm
Board Length 2.4m
Board Width 1.2m
Board Edge Square

Product Prices

Buy Celotex TB4000

Product ex-VAT inc-VAT
Celotex TB4020 20mm, 1.2x2.4m = 2.88m² £12.99 £15.58
Celotex TB4025 25mm, 1.2x2.4m = 2.88m² £13.85 £16.62
Celotex TB4030 30mm, 1.2x2.4m = 2.88m² £16.54 £19.84
Celotex TB4040 40mm, 1.2x2.4m = 2.88m² £19.36 £23.23

Reasonable stock levels are generally held at most of our depots. In some geographic locations, depots may stock alternates, however, we will contact you to discuss before proceeding with the order.

Where products need to be brought in from Celotex, please allow approx. 1 week for delivery.

  • Generally 1 or 3 working days for delivery
  • Generally 1 to 5 working days for delivery
  • Generally 5 to 10 working days for delivery
  • Special request or made to order item, allow extended lead times. Minimum order levels may apply.
  • Please call to check availability and approximate lead times

Product availability depends upon stock levels at closest depot and delivery logistics to geographic locations

Product Performance and Guides

Product Performance, Manufacturer Downloads, and Installation Guides

Product Performance

Thermal Conductivity 0.022 W/mK
Compressive Strength 120 kPa at 10% compression BS EN 826:2013
Vapour Resistance > 300 MNs/gm
Product Thickness Thermal Resistance kg/m²
Celotex TB4020 20mm 0.90 m²K/W 0.79 kg/m²
Celotex TB4025 25mm 1.10 m²K/W 0.95 kg/m²
Celotex TB4030 30mm 1.35 m²K/W 1.10 kg/m²
Celotex TB4040 40mm 1.80 m²K/W 1.41 kg/m²

Product Certificates

Please visit the Celotex website for product certificates.