TL;DR
- Mackay = Wind Region C cyclonic (AS/NZS 1170.2).
- All commercial rails must be certified for Region C, with project-specific engineering.
- Purlin analysis is mandatory on systems > 10 kW — don't skip it.
- Structural sign-off = insurer peace of mind + cyclone claim protection.
Why Mackay is different
Coastal Central QLD sits in Wind Region C under AS/NZS 1170.2 — the second-most severe wind classification in Australia. Design wind speeds for 500-year return can exceed 70 m/s. Rail and clamp systems rated for southern capitals are not sufficient.
Engineering process
- Site assessment: roof type (Trimdek, Kliplock, CustomOrb), purlin section size, span, pitch, topographic multiplier (Mt).
- Wind pressure calc: AS/NZS 1170.2 Region C with terrain category and topographic factors.
- Rail selection: Sunlock C+, Clenergy PV-ezRack SolarRoof, Radiant RT, with documented Region C compliance.
- Purlin analysis: dead + live + wind uplift. Independent structural engineer where required.
- Documentation: stamped drawings and calculation sheets for the client, certifier and insurer.
Rails we specify
| Rail | Region C certified | Typical use |
|---|---|---|
| Sunlock C+ | Yes | Trimdek/Kliplock rooftops, preferred choice |
| Clenergy PV-ezRack SolarRoof | Yes (specific accessories) | Tile and metal roofs |
| Radiant RT | Yes | Standing-seam roofs |
| Miro/Schletter commercial | Region A/B only — avoid | Not used in Mackay |
Common mistakes we see (and fix)
- Rails rated for Region A installed on Mackay commercial roofs — insurance void.
- Missing topographic multiplier for elevated suburbs (Richmond Hill, Mount Pleasant).
- Over-spanned purlins with too few brackets. Mackay spec = brackets every 1.2-1.4 m typical.
- No sign-off drawings for insurer — rejected after storm events.
Insurer documentation pack
We provide every commercial client with a compliance pack: structural calc, rail compliance certificate, installer declaration, CEC certificate of compliance, electrical test results. This pack is what an insurer asks for after a named storm/cyclone event.
FAQs
Does roof age affect solar install?
Yes. We assess purlin corrosion and cladding condition. If the roof is near end of life, we recommend re-roof before solar to avoid double-handling panels in 5-10 years.
Can solar panels survive a cyclone?
Correctly installed and certified, yes. Reputable Tier-1 panels are tested for wind loading well beyond residential requirements. Failure modes in Mackay cyclone events are almost always mounting-related, not panel failure.
Engineering-led commercial solar
Structural assessment and certified design for Mackay commercial rooftops.
See engineering