Rigid Foam Insulation Washers 45mm

These are square-profile flat washers, 45 mm × 45 mm × 2.5 mm, made exclusively from technical-grade polypropylene. Produced using precision injection moulding, they exhibit zero porosity, smooth edges, and repeatable thickness control — critical for consistent load distribution and thermal performance. Average mass per piece: 1.2 g; specific gravity: 0.90–0.91. They are intended for mechanical fixing of rigid insulation boards where maintaining uninterrupted thermal resistance is mandatory — especially at penetrations through high-performance PIR or phenolic foam. Their geometry avoids stress concentration while resisting creep under constant compressive load — verified per ISO 899-1 testing methodology. Used extensively by certified EWI installers, local authority housing maintenance teams, and specialist roofing contractors working on Passivhaus-aligned retrofits, listed building upgrades, and social housing stock improvements — always where longevity, regulatory alignment, and ease of audit trail matter.