PIR Insulation Board

What is PIR Insulation?

Polyisocyanurate (PIR) insulation is a type of rigid foam insulation backed with a foil layer, that is renowned for its exceptional thermal performance. It is a strong and light type of foam that keeps structures warm by trapping air inside. PIR insulation is lightweight, durable, and offers excellent fire resistance and thermal insulating properties, making it a super DIY-friendly solution that can easily be cut to size to fit rafters, joists and stud walls, and used as Cavity Wall Insulation. We also sell a Celotex PIR Insulated Plasterboard which is ideal to save time in stud wall applications. 

PIR Insulation - How to Install

Due to it’s versatile nature, there are many different uses for PIR Insulation and therefore many different ways to correctly install it. However, generally PIR insulation should be purchased to fit the depth of the cavity or space it is to fill. It can be cut to size to fit the height and width of cavities, joists and rafters using a sharp utility knife or handsaw for thicker boards. It is typically designed to be friction-fit to a space, meaning the boards should fit tightly and stay easily in place with no additional fixtures and fittings.

For precise installation instructions for your specific use case, it is recommended to consult your builder, architect or building inspector to ensure installation complies with building regulations. 

Celotex vs Recticel

Celotex and Recticel are both brands of foil-faced PIR board available in a range of thicknesses. They are comparable products made from similar materials and methods and from a construction perspective they have the same Fire Rating (Euroclass F Reaction to Fire classification, according to BS EN 13501-1)  and thermal conductivity value of 0.022 W/m.K and so are suitable for largely the same purposes and projects.