How and where to use guide
Rigid PIR Insulation 1200 x 2400 x 50mm
Typical applications and installation
This 50mm board is commonly installed in layered systems where multiple sheets are combined to meet building regulation thermal requirements. In walls, boards are typically fixed between studs or applied to masonry with adhesive or mechanical fixings. For floors, the board sits between joists or on concrete substrates, with adequate support to handle foot traffic and imposed loads. In roof applications, boards are laid between rafters or on roof decking, secured with appropriate fixings. Always follow the specific installation guidance for your chosen brand (Ecotherm, IKO, Mannok, Recticel or Unilin) as fixing methods and adhesive compatibility may vary.
- Walls: fix between timber studs or apply to masonry with adhesive and mechanical fixings
- Floors: install between joists or on concrete with support adequate for imposed loads
- Roofs: lay between rafters or on decking, secured with appropriate fixings
- Retrofit schemes: layer multiple boards to achieve required thermal performance
- Ensure boards are cut square and fitted tightly to minimise thermal bridging
Handling and site storage
PIR boards are lightweight and easy to handle on site, but must be stored flat and protected from weather. Keep boards dry and away from direct sunlight, which can degrade the foam. Stack boards horizontally on a level, clean surface with adequate ventilation underneath to prevent moisture ingress. Protect the top of the stack with a waterproof covering during storage. Handle boards carefully to avoid damage to edges and faces, as damaged areas reduce thermal performance and may allow moisture penetration.
- Store flat on a level, clean, dry surface
- Protect from rain and direct sunlight
- Ensure adequate ventilation beneath stacks
- Cover stacks with waterproof sheeting
- Handle carefully to avoid edge and face damage
Cutting and fitting
PIR boards can be cut to size using a fine-toothed saw, hot wire cutter or specialist foam saw. Measure twice and cut once to minimise waste. When fitting boards, ensure they are cut square and fitted tightly to adjacent boards and building elements to reduce thermal bridging. Gaps between boards should be sealed with expanding foam or appropriate sealant. The compressive strength of 175 kPa means boards will support typical floor loads when properly supported, but do not rely on the board alone to carry structural loads.
- Cut with fine-toothed saw, hot wire cutter or foam saw
- Fit boards tightly to minimise gaps and thermal bridging
- Seal gaps with expanding foam or appropriate sealant
- Ensure boards are fully supported on walls, floors and roofs
- Do not use boards as primary structural support
Performance and limitations
The thermal conductivity of 0.022 W/mK provides consistent insulation performance, but the 50mm thickness is typically used as part of a multi-layer system to meet modern building regulation U-values. The compressive strength of 175 kPa is adequate for floor, wall and roof applications when boards are properly supported, but boards must not be used as load-bearing elements. PIR foam is moisture-resistant but not waterproof; ensure adequate vapour control and drainage design in your insulation system. The board is combustible; check fire rating requirements for your specific application and ensure compliance with building regulations.
- 50mm thickness typically used in layered systems, not as single-layer solution
- Compressive strength 175 kPa adequate for supported applications only
- Moisture-resistant but not waterproof; design vapour control accordingly
- Combustible material; verify fire rating compliance with building regulations
- Thermal conductivity 0.022 W/mK remains consistent when properly installed and protected