Five-rib / trapezoidal
Five-rib roofing in NZ: the profiles, cost and installation differences
“Five-rib” is a useful category name rather than one manufacturer product. Metalcraft MC760/T-Rib and Dimond Hi Five are examples of trapezoidal profiles with five main ribs.
Material cost is often close to corrugate. RoofHub expects only a small installed premium on a comparable simple roof, mainly because cutting and flashing around ribs can require more labour.
- Category
- Trapezoidal long-run
- Example cover
- ~760–765 mm
- Example min pitch
- 3° on cited systems
- Reviewed
- 26 Sep 2026
What manufacturers call it
Different names, same broad profile family
Metalcraft describes MC760 as a five-rib trapezoidal profile with 760 mm cover and a stated 3° minimum pitch. Dimond's Hi Five also uses five ribs and publishes a nominal cover around 765 mm with a 3° minimum pitch.
This is why RoofHub groups several manufacturer names under “five-rib / trapezoidal” for pricing, while still linking back to the exact product specification.
Public material observations
Five-rib supply pricing is less transparent than the technical data
RoofHub currently has fewer directly comparable five-rib retail observations than corrugate. That is a data-quality limitation worth showing, not hiding.
| What | Typical range (NZD) | Basis | Notes |
|---|---|---|---|
| Zinc 5-rib roofing sheets by length (1.8m-4.2m) | $32.99–$74.99/item | material only · GST not stated | Hamilton/Tauranga · DIY Supply NZ |
| 0.5mm corrugated/five rib iron roofing sheets (per metre) | $17.49/lm | material only · incl GST | Waikato (Otorohanga), ships nationwide · Bitz and Piecez |
Low-pitch use
Five-rib profiles can work at lower pitches than conventional corrugate
The cited MC760 and Hi Five systems publish minimum pitches of 3°, compared with 8° for the cited corrugate systems. That does not make every five-rib profile interchangeable: sheet length, run-off, fixing, wind zone and manufacturer details still matter.
See roof pitch and area for the geometry side.
Sources
Sources and manufacturer references
- marketDIY Supply NZ — GST treatment not stated by source · supplier
- marketBitz and Piecez — GST included · supplier
- primaryMetalcraft Roofing — MC760 — Five-rib trapezoidal profile; 760 mm cover; 3° minimum pitch stated · manufacturer
- primaryDimond — Hi Five — Five-rib profile; nominal 765 mm cover; 3° minimum pitch · manufacturer
- primaryBuilding Performance — E2 External Moisture — New Zealand Building Code external-moisture requirements · government
FAQ
Five-rib roofing questions
Is five-rib roofing more expensive than corrugate?
Usually only slightly in RoofHub's working model for a comparable roof. Material pricing can be close; the small difference is mainly an allowance for more involved profile cutting and flashing details.
Is five-rib the same product from every manufacturer?
No. It is a category description. Rib dimensions, cover, thicknesses, fixing requirements and product names vary, so use the exact manufacturer specification for the selected profile.
Can five-rib roofing go on a lower pitch than corrugate?
Some NZ five-rib/trapezoidal systems can. The cited Metalcraft MC760 and Dimond Hi Five systems state 3° minimum pitch, while the cited corrugate systems state 8°. Exact project requirements still need checking.