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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 Thin-R Pitched Roof Insulation PIR Board 2400 x 1200 x 60mm

    Thin-R Pitched Roof on sloped roofs (ventilated, hybrid or warm) provides the most efficient U-Values with minimal intrusion into valuable living space. The roof construction is a critical element in...
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    Unilin Thin-R Pitched Roof Insulation PIR Board 2400 x 1200 x 80mm

    Thin-R Pitched Roof on sloped roofs (ventilated, hybrid or warm) provides the most efficient U-Values with minimal intrusion into valuable living space. The roof construction is a critical element in...
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    Unilin Thin-R Plus Hyfloor Insulation PIR Board T&G 2400 x 1200 x 100mm

    Ground Supported & Suspended Floors The floor in any building is an area of considerable downward heat loss when not properly insulated. Unilin has developed Hyfloor floor insulation to achieve lower...
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    Unilin Thin-R Plus Hyfloor Insulation PIR Board T&G 2400 x 1200 x 125mm

    Ground Supported & Suspended Floors The floor in any building is an area of considerable downward heat loss when not properly insulated. Unilin has developed Hyfloor floor insulation to achieve lower...
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    Unilin Thin-R Plus Hyfloor Insulation PIR Board T&G 2400 x 1200 x 150mm

    Ground Supported & Suspended Floors The floor in any building is an area of considerable downward heat loss when not properly insulated. Unilin has developed Hyfloor floor insulation to achieve lower...
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    Unilin Thin-R Plus Hyfloor Insulation PIR Board T&G 2400 x 1200 x 75mm

    Ground Supported & Suspended Floors The floor in any building is an area of considerable downward heat loss when not properly insulated. Unilin has developed Hyfloor floor insulation to achieve lower...
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    Unilin Thin-R Polyiso Strips Insulation PIR Board 1200 x 100 x 25mm

    Unilin Thin-R range is a foil faced Polyisocyanurate (PIR) insulation with a certified thermal conductivity as Low as 0.022 W/mK. Thin-R is also available with engineered jointing to provide improved...
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    Unilin Thin-R Polyiso Strips Insulation PIR Board 1200 x 150 x 25mm

    Unilin Thin-R range is a foil faced Polyisocyanurate (PIR) insulation with a certified thermal conductivity as Low as 0.022 W/mK. Thin-R is also available with engineered jointing to provide improved...
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    Unilin Thin-R Polyiso Strips Insulation PIR Board 1200 x 200 x 25mm

    Unilin Thin-R range is a foil faced Polyisocyanurate (PIR) insulation with a certified thermal conductivity as Low as 0.022 W/mK. Thin-R is also available with engineered jointing to provide improved...
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    Unilin Thin-R Polyiso Strips Insulation PIR Board 1200 x 250 x 25mm

    Unilin Thin-R range is a foil faced Polyisocyanurate (PIR) insulation with a certified thermal conductivity as Low as 0.022 W/mK. Thin-R is also available with engineered jointing to provide improved...
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    Unilin XT Thermal Liner DD Insulation PIR Board 2400 x 1200 x 50.5mm

    Drylining Wall Insulation Fixed with Adhesive Dabs Thin-R Thermal Liner (Dot & Dab) is a composite insulated panel of Unilin PIR wall insulation core with a composite kraft paper facing bonded to 12...
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    Unilin XT Thermal Liner DD Insulation PIR Board 2400 x 1200 x 52.5mm

    Drylining Wall Insulation Fixed with Adhesive Dabs Thin-R Thermal Liner (Dot & Dab) is a composite insulated panel of Unilin PIR wall insulation core with a composite kraft paper facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 32.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 37.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 50.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 52.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 62.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XT Thermal Liner MF Insulation PIR Board 2400 x 1200 x 72.5mm

    Drylining Wall Insulation – Mechanically Fixed Thin-R Thermal Liner (Mechanically Fixed) is a composite insulated panel of Unilin PIR Wall insulation core with a composite foil facing bonded to 12...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board 1200 x 450 x 100mm

    XO/CW is an innovative partial fill cavity wall insulation system incorporating robust facings, engineered jointing details, preformed corners and a certified lambda of 0.021 W/mK. This lower lambda...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board 1200 x 450 x 75mm

    XO/CW is an innovative partial fill cavity wall insulation system incorporating robust facings, engineered jointing details, preformed corners and a certified lambda of 0.021 W/mK. This lower lambda...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board 1200 x 450 x 80mm

    XO/CW is an innovative partial fill cavity wall insulation system incorporating robust facings, engineered jointing details, preformed corners and a certified lambda of 0.021 W/mK. This lower lambda...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board T&G 1200 x 450 x 100mm

    XtroLiner is an innovative partial fill wall cavity insulation system incorporating robust facings and preformed corners. The XO/CW jointing offers a practical on-site solution that results in a more...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board T&G 1200 x 450 x 60mm

    XtroLiner is an innovative partial fill wall cavity insulation system incorporating robust facings and preformed corners. The XO/CW jointing offers a practical on-site solution that results in a more...
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    Unilin XtroLiner Cavity Wall Insulation PIR Board T&G 1200 x 450 x 80mm

    XtroLiner is an innovative partial fill wall cavity insulation system incorporating robust facings and preformed corners. The XO/CW jointing offers a practical on-site solution that results in a more...

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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