How and where to use guide
Rigid PIR Insulation 1200 x 2400 x 70mm
Typical applications
These PIR boards are suitable for a wide range of building applications where thermal performance and structural rigidity are required. The closed-cell foam properties and foil facing make them particularly effective in moisture-prone environments.
- Wall insulation in new build and retrofit projects, including cavity fill and external wall systems
- Floor insulation beneath concrete slabs and timber joists where load-bearing capacity is needed
- Roof insulation in pitched and flat roof constructions
- Refurbishment projects where space constraints favour thinner, high-performance boards
Installation and handling
The board dimensions of 1200 x 2400mm are designed for straightforward handling and installation on site. Plan your layout to minimise waste and ensure boards are supported adequately during and after installation.
- Store boards flat and dry on site, protected from weather and direct sunlight before installation
- Handle carefully to avoid damage to the foil facing, which is essential for vapour control
- Cut boards using a fine-toothed saw or hot-wire cutter; wear appropriate PPE including dust mask and gloves
- Ensure boards are fully supported and fixed securely according to the specific application and building design
- Stagger joints between boards to avoid continuous weak points in the insulation layer
Vapour control and moisture management
The foil facing provides vapour control, which is critical for protecting the insulation and underlying building elements from moisture accumulation. Correct installation of the facing is essential to maintain thermal and structural performance.
- Position the foil facing on the warm side of the insulation layer to prevent interstitial condensation
- Seal all joints and edges with appropriate tape or sealant to maintain vapour control integrity
- Ensure adequate ventilation on the cold side of the insulation to manage any residual moisture
Performance and limitations
At 70mm thickness with 0.022 W/mK thermal conductivity, these boards provide effective insulation performance for most standard building applications. The compressive strength of 175 kPa is suitable for typical floor and roof loads, but site-specific structural calculations may be required for unusual loading conditions.
- Verify that 70mm thickness meets your Building Regulations U-value requirements for the specific application
- Do not rely on PIR boards alone to support concentrated loads; ensure adequate structural support beneath
- PIR foam is combustible; check fire safety requirements for your application and ensure appropriate fire barriers are in place where required by Building Regulations