Metric Roofing Bolts With Square Nuts BZP

Perfect for Lightweight Assemblies

When working with thin sheet metal, plastics, or soft woods, standard hex bolts can often be too aggressive, crushing the material or pulling right through it. Our Grade 4.8 Mushroom Head Roofing Bolts are the specific solution for these delicate yet demanding applications. Whether you are fixing corrugated roofing sheets, assembling metal shelving, or securing cable trays, these bolts provide the gentle yet secure clamping force required.

Engineered for Surface Protection

The defining feature of this bolt is its "mushroom" head—a wide, domed profile that significantly increases the bearing surface area. By spreading the clamping load over a wider diameter, the bolt prevents the head from sinking into or damaging the material surface. This is critical when working with soft substrates like timber battens or thin-gauge metals where maintaining surface integrity is key. The cross-slot drive ensures they can be tightened easily with a standard screwdriver, making them accessible for both professional contractors and home DIY enthusiasts.

Ready-to-Use with Durability

Every bolt is supplied with a corresponding square nut, a traditional fastening choice that offers excellent grip and stability, particularly when used in pre-formed channels or tight spaces. Manufactured from Grade 4.8 Mild Steel, these bolts are tough enough for general fastening tasks where high-tensile strength is not required. The Bright Zinc Plated (BZP) finish adds a layer of sacrificial protection against rust and oxidation, ensuring your fixtures remain secure and looking clean in dry or sheltered environments.