Colorbond Ultra (severe-exposure variant)
Colorbond Ultra is BlueScope's marine/severe-exposure roofing with upgraded paint and primer. Required within 1 km of breaking surf; 15-25% premium over standard.
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Colorbond Ultra is BlueScope’s severe-exposure variant of standard Colorbond steel, with upgraded paint and primer formulation specifically for marine and severe-exposure coastal conditions. Recommended within 1 km of breaking surf, where standard Colorbond degrades materially faster than its 25-year aesthetic warranty supports. Premium over standard Colorbond is typically 15-25% on the cost of the material. Use it where the warranty matters; standard Colorbond suffices for non-coastal residential, mild coastal (>1 km from surf), and inland.
What it is
| Layer | Standard Colorbond | Colorbond Ultra |
|---|---|---|
| Base steel | Hot-dip Zincalume coated (AS 1397) | Hot-dip Zincalume coated, same base |
| Primer | Standard | Marine-grade primer for severe corrosion resistance |
| Top coat | Standard polyester paint | Enhanced fluoropolymer / specialty topcoat (higher UV and salt resistance) |
| Backing coat | Standard | Enhanced |
The base steel is the same; the paint and primer system is what’s upgraded. The warranty backing reflects the upgraded performance: Ultra carries a longer warranty in severe environments where standard Colorbond’s warranty doesn’t apply.
Properties
| Property | Standard Colorbond | Colorbond Ultra |
|---|---|---|
| Base steel thickness | 0.42 mm typical | Same |
| Aesthetic warranty (residential, inland) | 25 years | 25 years (same) |
| Aesthetic warranty (mild coastal, 1-15 km) | 25 years | 25 years (same) |
| Aesthetic warranty (severe marine, <1 km) | Excluded / reduced | 25 years (within terms) |
| Cost | Baseline | +15-25% premium |
Where to use Colorbond Ultra
- Within 1 km of breaking surf: standard recommendation.
- Pool surrounds and pool-house roofing: chlorine exposure.
- Industrial coastal: refinery, dock, port-adjacent residential.
- High-end residential where 25-year aesthetic is contractual: even in mild coastal, Ultra removes the marginal risk.
Where standard Colorbond suffices
- Inland residential (>15 km from coast).
- Mild coastal (1-15 km from breaking surf): standard warranty applies.
- Cost-sensitive volume residential even in marginal-coastal zones (accept the warranty risk).
Where neither suffices
- Splash zone / breaking-surf direct exposure: even Ultra’s warranty has limits. Consider stainless steel cladding or specialty marine products.
- Industrial chemical exposure (acid mist, ammonia, etc.): chemistry-specific products required.
Cost band (2026 AUD ex-GST, residential)
| Item | Standard Colorbond | Colorbond Ultra |
|---|---|---|
| Roof sheet (per m²) | $25-$40 | $30-$50 |
| Installation labour (per m²) | $25-$50 | Same |
| Flashings, ridge, fascia | $15-$30 lin.m | $18-$35 lin.m |
| Total premium on a 200 m² roof | Baseline | +$1,500-$3,000 |
For coastal residential, the Ultra premium is small money against the cost of re-roofing in 10-15 years when standard Colorbond has corroded prematurely.
Where NOT to use it
- Indoor or sheltered: overspec.
- Inland >15 km from coast: standard suffices.
- Walling only (not roof) where roof is standard: aesthetic mismatch can happen over time.
Fixing / installation
- AS 1562.1 install standard applies to both. Same fixings, same overlaps, same flashings.
- Stainless 304 or 316 fasteners required for severe coastal regardless of Colorbond variant.
- Cut edges: prime cut edges with manufacturer’s touch-up paint to maintain the coating system.
Common builder errors
| Error | Cost |
|---|---|
| Standard Colorbond within 1 km surf | Premature corrosion; warranty excluded |
| Ultra inland | Overspec; wasted cost |
| Mixed Ultra + standard fasteners | Standard fasteners corrode first; aesthetic problem |
| Cut edges not touched up | Edge corrosion compromises whole sheet |
For builders
- Map the site against the BlueScope coastal exposure map (free, online).
- Spec Ultra within 1 km of breaking surf: don’t try to save 15-25% on a coastal job.
- Spec stainless 304+ fasteners for any Ultra installation.
- Brief the roofer on cut-edge touch-up: BlueScope-supplied touch-up paint, applied within the day of cutting.
- Document the BlueScope warranty registration: required to claim later.
References
-
BlueScope Colorbond range: https://colorbond.com (verified 2026-05-16).
-
BlueScope coastal exposure map: https://www.bluescope.com/products/colorbond/environmental-categories/ (verified 2026-05-16).
Related
See also
Last updated: 2026-05-16. Verified: 2026-05-16.