Below 8°, 16.5 mm corrugate is out. This comparison is the next CoP rows. Full family notes: NZ longrun profiles. Product page for Hi Five: Hi Five on a low-pitch job. Calculator: trapezoidal.
| Profile | Min cladding pitch | Cover (library) | Check run | Notes |
|---|---|---|---|---|
| Dimond Six Rib | 4° | 760 mm (820 mm overall) | 20 m | ~20 mm rib. Usual step down from corrugate. |
| Dimond Hi Five | 3° | 765 mm (some sheets 755 mm; 810 mm overall) | 40 m | ~27 mm five-rib. South Island supply listed. |
| Metalcraft T-Rib | 3° | 760 mm | 40 m | Same CoP row as Hi Five; different roll. Do not mix. |
| Tray / secret-fix | typically 3° | override (library 300 mm) | product sheet | Clips, pans, seams — not a rib count. |
Minima are cladding pitch after deflection. A 3° drawing with wide purlins can still pond. Do not “sealant” a profile under its table.
Count and run
Cover, not overall: 9.2 m ÷ 0.765 m = 12.03 → 13 Hi Five sheets. Using 810 mm gives 12 and a shortage.
Long + flat is a drainage problem. Record run separately from width. Hi Five’s 40 m check is longer than Six Rib’s 20 m; a 22 m Six Rib at 4° should not get a silent pass. Tray run and clip spacing are on that pan’s sheet.
Flashings at low pitch and Extra High need Category B covers (flashing checklist). Waste still follows hips and valleys.
Pick by the limiting condition
- Roof under 4° (and ≥3°): Hi Five or T-Rib or a named tray — not Six Rib, not corrugate.
- 4–8°: Six Rib is usually enough if run ≤20 m; confirm the sheet.
- Tray only after the pan, clips and min pitch are written down.
- Hi Five only after availability (island) and 765 vs 755 mm cover are confirmed.
Open the takeoff, set the named profile and the actual pitch, and read the min-pitch and run warnings before coil is cut. NZMRM CoP and the manufacturer sheet remain the authority.