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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 XtroLiner Framing Insulation PIR Board 2400 x 1200 x 50mm

    XtroLiner XO/FB is a PIR foamboard which has been specifically developed for use as a thermally efficient insulation board in building constructions. XO/FB is designed for use in a wide range of construction including steel or timber frame applications...
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    Unilin XtroLiner Framing Insulation PIR Board 2400 x 1200 x 80mm

    XtroLiner XO/FB is a PIR foamboard which has been specifically developed for use as a thermally efficient insulation board in building constructions. XO/FB is designed for use in a wide range of construction including steel or timber frame applications...
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    Unilin XtroLiner Framing Insulation PIR Board 2400 x 1200 x 90mm

    XtroLiner XO/FB is a PIR foamboard which has been specifically developed for use as a thermally efficient insulation board in building constructions. XO/FB is designed for use in a wide range of construction including steel or timber frame applications...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 100mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 30mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 40mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 50mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 80mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Pitched Roof Insulation PIR Board 2400 x 1200 x 90mm

    A pitched roof is the most efficient U-value with minimal intrusion into valuable living space. Xtraliner Xtroliner Pitched Roof Insulation PIR Board provides high resistance to heat loss with minimal intrusion into valuable living space. Using Xtrolley...
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    Unilin XtroLiner Soffit Plus Insulation PIR Board 2400 x 1200 x 106mm

    Unilin / Xtratherm XtroLiner Soffit Plus is an effective thermal and fire protection solution, in structural ceiling applications. The high performance modified PIR insulation board, with low emissivity textured aluminium foil facings, is adhesively...
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    Unilin XtroLiner Soffit Plus Insulation PIR Board 2400 x 1200 x 126mm

    Unilin / Xtratherm XtroLiner Soffit Plus is an effective thermal and fire protection solution, in structural ceiling applications. The high performance modified PIR insulation board, with low emissivity textured aluminium foil facings, is adhesively...
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    Unilin XtroLiner Soffit Plus Insulation PIR Board 2400 x 1200 x 81mm

    Unilin / Xtratherm XtroLiner Soffit Plus is an effective thermal and fire protection solution, in structural ceiling applications. The high performance modified PIR insulation board, with low emissivity textured aluminium foil facings, is adhesively...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 100mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 30mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 40mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 50mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 80mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Unilin XtroLiner Underfloor Insulation PIR Board 2400 x 1200 x 90mm

    XtroLiner XO/UF underfloor insulation board is the perfect solution for insulating floors. It has a thermal conductivity of 0.021 W/mK, making it excellent for improving U-Values and R-Values. This product has also been Euroclass C Certified for Fire...
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    Xtratherm Thin-R Cavity Fill PIR Insulation Board T&G 1200 x 450 x 115mm (XT/CF/115/BD/RB01)

    Thin-R Partial Fill Cavity Wall (T&G) builds to a system thanks to its engineered tongue and grooved joint and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging. Cavity Wall (T&G) for use in traditional masonry...
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    Xtratherm Thin-R Cavity Fill PIR Insulation Board T&G 1200 x 450 x 140mm (XT/CF/140/BD/RB01)

    Thin-R Partial Fill Cavity Wall (T&G) builds to a system thanks to its engineered tongue and grooved joint and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging. Cavity Wall (T&G) for use in traditional masonry...
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    Xtratherm Thin-R Cavity Fill PIR Insulation Board T&G 1200 x 450 x 90mm (XT/CF/090/BD/RB01)

    Thin-R Partial Fill Cavity Wall (T&G) builds to a system thanks to its engineered tongue and grooved joint and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging. Cavity Wall (T&G) for use in traditional masonry...

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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