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PIR Insulation Board

PIR insulation, also called Polyisocyanurate or PIR board, is a high-performance, rigid foam insulation with excellent thermal conductivity. It is moisture resistant and offers strong fire resistance. Suitable for lofts, floors, and walls, PIR board is space-saving thanks to its thin design. Our range of PIR insulation includes various sizes from Unilin.

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    Unilin ECO CavityTherm External Corner Insulation PIR Board 1200 x 450 x 125mm

    The CavityTherm pre-cut corner boards are designed to provide a precise and efficient solution for achieving consistent detailing at cavity wall corners. Where required, corners can also be formed on...
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    Unilin ECO CavityTherm External Corner Insulation PIR Board 1200 x 450 x 150mm

    The CavityTherm pre-cut corner boards are designed to provide a precise and efficient solution for achieving consistent detailing at cavity wall corners. Where required, corners can also be formed on...
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    Unilin ECO CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 110mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin ECO CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 125mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin ECO CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 150mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin ECO CavityTherm Internal Corner Insulation PIR Board 1200 x 450 x 110mm

    The CavityTherm pre-cut corner boards are designed to provide a precise and efficient solution for achieving consistent detailing at cavity wall corners. Where required, corners can also be formed on...
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    Unilin ECO CavityTherm Internal Corner Insulation PIR Board 1200 x 450 x 125mm

    The CavityTherm pre-cut corner boards are designed to provide a precise and efficient solution for achieving consistent detailing at cavity wall corners. Where required, corners can also be formed on...
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    Unilin ECO Multi Application Insulation PIR Board 2400 x 1200 x 100mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin ECO Multi Application Insulation PIR Board 2400 x 1200 x 125mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin ECO Multi Application Insulation PIR Board 2400 x 1200 x 150mm

    An engineered system providing added resilience against increases in wind-driven rain resulting from climate change. ECO/CT is a bio-enhanced high performance composite board of enhanced PIR with a...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 106mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 116mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 126mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 131mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 136mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 146mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 156mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 76mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 81mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Roof Thermal Ply Insulation PIR Board 2400 x 1200 x 96mm

    High Performance PIR and Plywood Composite Thermal Ply is a composite insulated panel of Unilin Polyisocyanurate core with a composite foil face, bonded to 6mm WBP grade plywood. It is designed to...
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    Unilin Safe-R Cavity Wall Insulation PIR Board 1200 x 450 x 100mm

    Our Safe-R SR/CW Cavity Wall Insulation is an aircrete insulation for traditional masonry cavity walls. The product is designed to achieve excellent U-Values whilst maintaining a residual cavity,...
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    Unilin Safe-R Cavity Wall Insulation PIR Board 1200 x 450 x 50mm

    Insulation for Partial Fill Cavity Walls Safe-R SR/CW Partial Fill cavity insulation for traditional masonry walls, achieves improved U-Values whilst maintaining a residual cavity, offering...
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    Unilin Safe-R Cavity Wall Insulation PIR Board 1200 x 450 x 60mm

    Insulation for Partial Fill Cavity Walls Safe-R SR/CW Partial Fill cavity insulation for traditional masonry walls, achieves improved U-Values whilst maintaining a residual cavity, offering...
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    Unilin Safe-R Cavity Wall Insulation PIR Board 1200 x 450 x 75mm

    Our Safe-R SR/CW Cavity Wall Insulation is an aircrete insulation for traditional masonry cavity walls. The product is designed to achieve excellent U-Values whilst maintaining a residual cavity,...

PIR Insulation Board

What are PIR boards?

PIR stands for Polyisocyanurate — a rigid type of thermal insulation made from plastic foam.

First introduced in the 1960s as an upgrade to PUR (Polyurethane) boards, PIR offers better insulation performance and versatility.

Where can PIR Insulation be used?

  • Walls – Products like Ecoliner are ideal for insulating and drylining internal walls. Eco-Versal suits timber frame walls, with both sides faced in aluminium foil for improved efficiency. As the name suggests, Eco Cavity is designed for cavity or masonry walls and fits standard brick and block dimensions.
  • Flooring – Works with most flooring types, including timber, solid concrete, and suspended floors. Insulating floors helps prevent heat loss and keeps interiors warmer.
  • Lofts – Loft spaces are one of the most common areas for heat loss. Using PIR or PUR insulation can improve energy efficiency and reduce heating costs.
  • Eco-Versal versatility – A popular PIR option that works across pitched roofs, walls, loft ceilings, and floors for consistent thermal performance throughout the home.

Frequently Asked Questions

What is pir insulation?
Polyisocyanurate (PIR) is one of the most efficient insulation materials used in construction. Pir insulation boards are typically available in the following sizes: 25mm, 75mm, 100mm, 120mm and 150mm.
What does pir stand for in pir insulation?
Polyisocyanurate, also referred to as PIR, is a thermoset plastic typically produced as a foam and used as rigid thermal insulation.
Is pir insulation flammable?
Whilst we urge you to refer to the manufacturer’s fire testing certifications, commercially available PIR insulation is not typically flammable.
Is pir insulation waterproof?
While PIR insulation boards are generally resistant to moisture, they are not fully waterproof.
What is the difference between pir and phenolic insulation?
As with the PIR/PUR boards above, phenolic insulation boards also have a closed cell structure. Phenolic board has a slightly higher r-value (higher is better, unlike u-values) and a slightly thinner profile than PIR/PUR boards due to the manufacturing process.

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