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![ECOCT%20EXT%20CRN.jpg.jpeg]( "ECOCT%20EXT%20CRN.jpg.jpeg")
Unilin CavityTherm Full Fill Ext Corner Insulation PIR Board 1200 x 450 x 125mm
CavityTherm Corner Fill is a preformed panel of CavityTherm that folds to provide a 90° corner either external or internal. Corner boards ensure excellent detailing and provide a template for setting out of outer brickwork. -
![CavityTherm%20Board.jpg.jpeg]( "CavityTherm%20Board.jpg.jpeg")
Unilin CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 100mm
CavityTherm is an innovative built-in insulation for traditional walls that achieves passive level U-Values as low as 0.12 W/m2K with excellent thermal bridging detailing in cavities less than 150mm wide. The board includes specifically designed rebated... -
![CavityTherm%20Board.jpg.jpeg]( "CavityTherm%20Board.jpg.jpeg")
Unilin CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 125mm
CavityTherm is an innovative built-in insulation for traditional walls that achieves passive level U-Values as low as 0.12 W/m2K with excellent thermal bridging detailing in cavities less than 150mm wide. The board includes specifically designed rebated... -
![CavityTherm%20Board.jpg.jpeg]( "CavityTherm%20Board.jpg.jpeg")
Unilin CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 150mm
CavityTherm is an innovative built-in insulation for traditional walls that achieves passive level U-Values as low as 0.12 W/m2K with excellent thermal bridging detailing in cavities less than 150mm wide. The board includes specifically designed rebated... -
![CavityTherm%20Board.jpg.jpeg]( "CavityTherm%20Board.jpg.jpeg")
Unilin CavityTherm Full Fill Insulation PIR Board 1200 x 450 x 90mm
CavityTherm is an innovative built-in insulation for traditional walls that achieves passive level U-Values as low as 0.12 W/m2K with excellent thermal bridging detailing in cavities less than 150mm wide. The board includes specifically designed rebated...
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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How to insulate a garage
A step-by-step guide on how to insulate your garage. Find out more.
How to insulate a shed
A step-by-step guide on how to insulate your shed. Find out more.