Description

Install roofing sheets fast and securely with these 25 mm self-drilling hex head screws—engineered for clean penetration, tight sealing, and long-term corrosion resistance. They are ideal for fixing mabati (corrugated, box-profile, or tile-profile) roofing sheets to timber or light-gauge steel purlins without pre-drilling.

Why choose Self Drilling Roofing Screws

• One-step drilling & fastening: Self-drilling point bites quickly and forms a strong, consistent thread—no pilot hole required in most applications.
• Leak-proof seal: Fitted with a high-quality EPDM bonded washer that compresses under the hex head to block water ingress and resist UV, heat, and movement.
• Corrosion-resistant finish: Zinc-plated (or class-rated coating where specified) to protect against rust in typical Kenyan inland conditions. (For coastal or highly corrosive sites, request marine-grade options.)
• Strong hold, clean finish: Wide hex flange spreads load to reduce sheet damage and “pull-through,” leaving a neat, professional look.
• Fast, consistent installations: 5/16″ (8 mm) hex drive for positive grip with minimal cam-out—perfect for roofing crews and DIY alike.

Typical applications

• Fixing corrugated, box-profile, and tile-profile steel sheets to purlins
• Ridge caps, barge boards, and side laps (use with appropriate length and washer size)
• Residential, commercial, and light industrial roofing and cladding projects
• Fixing meral to metal applications
• Fixing polycabonate sheets

Technical details

• Head type: Hex flange head (takes 5/16″ / 8 mm hex socket)
• Length: 25 mm (best for crest-fixing thin to medium roof sheets where minimal penetration is required)
• Thread: Self-tapping roofing thread for strong grip in steel or timber
• Point: Self-drilling (commonly #2) for light-gauge steel up to ~2.0–2.5 mm or timber purlins
• Washer: 14 mm–16 mm EPDM bonded sealing washer (non-staining, UV-resistant)
• Material/finish: Carbon steel with anti-corrosion coating (e.g., zinc). Stainless variants available on request
• Recommended substrates:
  • Steel purlins: ~0.8–2.5 mm
  • Timber purlins: softwood/hardwood
• Color options: Natural (silver) as standard; color-matched heads to popular roof sheet colours available on request
• Compliance: Manufactured to common roofing-fastener tolerances; batch quality checks for drill performance and pull-out strength

Choosing the right length

• 25 mm suits crest-fixing thin roofing sheets where the screw only needs to pass the sheet crown and bite firmly into the purlin without excessive protrusion.
• For thicker insulation layers, deep profiles, or valley-fixing, select a longer screw to maintain minimum embedment.

Installation tips

1. Use a variable-speed drill/driver with 5/16″ hex magnetic socket.
2. Drive perpendicular to the sheet; allow the drill point to cut—avoid over-speeding.
3. Stop once the EPDM washer just compresses (no bulging) to maintain a weather-tight seal.
4. Space fasteners per sheet manufacturer guidance (typically at every second crest for intermediate purlins and every crest at edges/ridges).
5. Avoid mixing dissimilar metals in coastal/aggressive environments; consider stainless or higher-class coatings.

Benefits at a glance

• Fast, no-pilot installation
• Reliable weather seal with EPDM
• Strong pull-out and pull-over resistance
• Neat, professional roof finish
• Cost-effective and durable

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