Carbon Steel Countersunk Timber to Heavy Section

For fixing timber to hot rolled purlins (4.0mm – 12.5mm steel).


This standard anti-corrosion coating ensures our fasteners can withstand over 500 hours in a salt spray test. It is a specialist epoxy zinc and aluminium compound which produces a multi layered, scratch resistant coating.  Countersunk heads lie flush with the surface of the substrate. They generally have a torx drive.

Part Number Length (MM) Diameter (MM) Drill Point Min Timber Thickness (MM) Max Timber Thickness (MM)
60.5T 60 5.5 No. 5 6 25
80.5T 80 5.5 No. 5 25 45
100.5T 100 5.5 No. 5 40 60
120.5T 120 5.5 No. 5 45 85
150.5T 150 5.5 No. 5 50 115
175.5T 175 5.5 No. 5 60 145
200.5T 200 5.5 No. 5 80 165

Timber screws fasten timber to cold rolled purlins (1.5mm – 5.0mm steel).

  • Carbon steel is the most popular material for fixings as it is strong, weather resistant and affordable.
  • Countersunk heads lie flush with the profile, and require T-25 bits.
  • The fine thread provides many points of engagement with the purlin, maximising pull-out values.
  • The wings bore through the timber and keep the thread clean, before snapping off when they connect with the steelwork.
  • The no. 5 drill point is designed to ensure a clean cut through up to 12.5mm steel, without burn-out.

For maximum fastener performance, we recommend using a tek screw driver which does not exceed 2500RPM.







Related Products