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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.
How to guides
What is the Green Homes Grant?
The £2 billion grant aims to encourage homeowners to make their homes more energy efficient, benefitting the environment as well as protecting and creating jobs.
Insulation for every application
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