20mm Celotex TB4020 PIR Insulation Board 2400mm x 1200mm

About 20mm Celotex

Celotex TB4020 is a premium Polyisocyanurate (PIR) insulation board specifically engineered for construction scenarios where insulation thickness is a primary constraint or where precise, targeted thermal upgrades are necessary. 

As part of the established Celotex TB4000 range, TB4020 embodies the series' focus on effectively addressing thermal bridging challenges and enhancing the overall thermal integrity of the building envelope. A defining characteristic is its dual-sided facing of low-emissivity composite aluminium foil, designed to enhance thermal performance. The foil surface has low emissivity, meaning it radiates (emits) very little heat. When facing an unventilated air space within a construction (e.g., between wall studs or rafters), this property significantly reduces heat transfer by radiation across the gap.

Primary Purpose

• Addressing Thermal Bridging: Specifically designed to combat localised heat loss paths, often found at junctions and openings, thereby improving the continuity of the building's thermal envelope.   
• Multi-Layer Systems: Serving as a component within a thicker overall insulation build-up.
• Space-Constrained Applications: Providing a thermal upgrade solution where minimal insulation thickness is permissible or achievable.

Understanding Thermal Bridges 

Thermal bridges (or cold bridges) are areas within the building envelope where the continuity of the insulation layer is interrupted, creating pathways of lower thermal resistance through which heat can escape more easily. Common locations include junctions between walls, floors, and roofs; around openings like windows and doors (reveals); and where structural elements like studs or beams penetrate the insulation layer. 

These bridges not only lead to significant heat loss (potentially up to 30% of total fabric heat loss ) but also create cold internal surfaces where condensation can form, potentially leading to mould growth and impacting occupant comfort and health.   

Applications

Roofs

• Pitched Roof Insulation: Below Timber Rafters, Above Timber Rafters

Walls

• External Wall Insulation: Timber Frame Internal Linings, Masonry Cavity Internal Linings, Solid Masonry Internal Linings
• Partition Walls

Floors

• Ground Floor Insulation: Beam & Block (Perimeter Upstand), Concrete Slab (Perimeter Upstand), Suspended Timber Joists (Perimeter Upstand), Upgrading Existing Concrete Slab (Perimeter Upstand)

Benefits

• Excellent Thermal Performance - 0.022 W/m·K thermal conductivity reduces insulation thickness required to meet U-values.
• Moisture Resistant - Prevents water absorption, maintaining thermal efficiency.
• Environmentally Responsible - Zero GWP and ODP, supporting sustainable construction.
• Cost-Effective - Provides high performance at a competitive price.
• Non-Toxic - Safe to handle and install, with no harmful emissions.
• Low-Emissivity Foil Facings - Improves thermal insulation within cavity air spaces.

Certifications

• Spread of Flame: Euroclass E Reaction to Fire classification (BS EN 13501-1).
• Thermal Conductivity: 0.022 W/m·K (BS EN 12667).
• Compressive Strength: ≥140kPa (BS EN 826).
• BRE Green Guide Rating of A - Supports BREEAM sustainability assessments.
• BBA Certified - Independently assessed for performance and compliance.