Trade Quality 40mm Roofing Screw, Self-Drilling Hex Head, EPDM Washer

40mm Self-Drilling Fastener

The 40mm Roofing Screw is a high-performance fastener engineered for securing corrugated metal sheets or box-profile cladding to timber and light-gauge steel purlins. This heavy-duty fixing features a precision-engineered drill point that eliminates the need for pre-drilling in most standard roofing applications. Every unit comes equipped with a bonded EPDM sealing washer to ensure a weather-tight finish across the entire roof surface.

Built for the Job

Contractors and roofers utilize this hardware for residential, industrial, and agricultural roofing projects. The 40mm length is specifically chosen for securing the valleys of roofing sheets where a shorter grip length is required compared to ridge-cap installations. It provides sufficient penetration into the supporting structure to resist wind uplift forces. The self-drilling tip is designed to cut through metal cladding and drive into the underlying frame in one continuous motion, significantly reducing installation time on large-scale sites.

• Fixing IBR or corrugated metal sheets to timber purlins.

• Securing side-cladding on industrial steel-frame warehouses.

• Installing polycarbonate or fiberglass translucent roof panels.

Product Highlights

Corrosion Resistance

The carbon steel body features a high-grade zinc plating to protect the fastener against oxidation and atmospheric moisture in outdoor environments.

Sealing Performance

• 16mm bonded EPDM washer prevents water ingress at the puncture point.
• The rubber seal remains flexible under UV exposure to maintain a long-term bond.
• The washer profile distributes pressure evenly to avoid sheet deformation.

Drive System

An 8mm (5/16″) hexagonal head allows for high-torque application using a standard nut setter without the risk of cam-out or head stripping.

Technical Specifications

What’s Included

• 1 x 40mm Self-Drilling Screw with pre-fitted EPDM washer

On-Site & Workshop Notes

• Ensure the drill driver is set to a medium torque to seat the washer without over-compressing the rubber seal.

• For timber applications, ensure the thread achieves a minimum of 25mm penetration into the wood for maximum pull-out resistance.

• These fasteners are sold per piece; calculate the total count based on 4-6 fixings per square meter of roofing depending on wind load requirements.