Metal Insulation Discs – Galvanised

Galvanised metal insulation discs are one of those fixings that don’t get much attention until you need them, and then suddenly they’re the most important thing on site. The large diameter head spreads the load across the face of insulation board, stopping the screw from pulling straight through the material. Without them, you’re relying on the screw head alone to hold soft insulation in place, which rarely ends well, especially on ceilings or vertical surfaces where gravity has opinions.

These are hot-dip galvanised steel discs, so they’ll handle the damp conditions you’d expect behind cladding, in roof spaces, or anywhere insulation is being fixed to a timber or metal batten. Galvanising gives them the corrosion resistance you need for long-term installations where access later isn’t always straightforward.

Where Galvanised Metal Insulation Discs Get Used

The most common use is fixing rigid or semi-rigid insulation boards to timber battens during wall and roof installations. The disc sits flat against the face of the insulation, the screw passes through the disc and drives into the batten behind, and the wide bearing surface keeps the board firmly in place without damaging the material. It’s a simple system that works reliably across a wide range of board thicknesses and densities.

They’re also widely used for ceiling crack repairs. A disc positioned over a crack in a plasterboard or older lath-and-plaster ceiling, fixed back through to the substrate, pulls the surface back flat before skimming. It’s a neat way to stabilise the crack without cutting out and patching, which is particularly useful in older properties where matching existing finishes is awkward.

Choosing the Right Size

The 35mm disc is the go-to for lighter fixings and ceiling repair work where a smaller footprint is fine. The 70mm and 80mm discs are better suited to holding thicker or heavier insulation boards, where the extra bearing surface makes a real difference to pull-through resistance. If you’re fixing to a surface where the insulation is under any lateral load or compression, go larger rather than smaller. It costs nothing extra and saves the frustration of refixing boards that have shifted.

Available in packs of 100 for 35mm and 70mm, and packs of 50 for the 80mm size. Straightforward pricing, no minimum fuss, and next day delivery available if you need them on site quickly.