PRODUCT FAMILY 04 · COLD-FORMED
Cold-formed C and Z profiles, punched to your purlin pattern.
Purlins, side rails and light posts, roll-formed from galvanised coil, cut to bay length and punched before packing. The profile is what the cover is actually fixed to, so its spacing and its hole pattern decide how fast a house goes up.
A purlin is not a commodity line. Two houses with the same arches and different purlin spacing behave differently under wind uplift, and a purlin punched 50 mm off pattern costs a day on site. We quote purlins with the hole pattern attached: spacing, hole diameter, and whether the fixing is a self-drilling screw, a bolt or a clip.
| Profile | Developed width | Wall | kg/m | Usual duty |
|---|---|---|---|---|
| C 80×40×15 | 168 mm | 1.8 / 2.0 | ≈ 2.37 / 2.63 | Purlin, light rail |
| C 100×50×20 | 216 mm | 2.0 / 2.5 | ≈ 3.39 / 4.24 | Purlin, side rail |
| Z 100×40×15 | 214 mm | 2.0 / 2.5 | ≈ 3.36 / 4.20 | Purlin, lapped runs |
| Z 120×50×20 | 254 mm | 2.0 / 2.5 | ≈ 3.99 / 4.98 | Long purlin runs, roof |
Weights are nominal, from developed width × wall × 7.85 g/cm³. Section properties come from the mill's profile sheet.
Why Z for long runs
A Z profile laps with the next piece, so a purlin run can continue past a bay without a butt joint on a fixing line. A C profile butts end to end and needs a sleeve or a bracket. On houses longer than four bays the lapped Z is usually cheaper to install even when the steel costs the same.
- Profiles
- C 80×40×15 / C 100×50×20 / Z 100×40×15 / Z 120×50×20
- Wall
- 1.8 / 2.0 / 2.5 mm
- Length
- cut to bay, up to 12 m
- Coil
- Z275 pre-galvanised
- Punching
- CNC, pattern per drawing
- Hole diameter
- 6.5 / 8.0 / 10.0 mm
- Ends
- square cut, deburred
- Packing
- nested bundles by length
- Tolerance
- ±1 mm length
- Hole pitch
- per drawing
- Marking
- bundle + bay ref
- Loading
- 40HQ, nested
Profile pages
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Send the sizes, wall thicknesses and quantities you need. We reply with a line-by-line offer, bundle weights and the loading plan for your container.