Our Corten steel siding is engineered from weathering steel designed for long-term exterior performance. Beyond its distinctive rusted appearance, it delivers measurable durability, structural reliability, and lifecycle cost advantages.
Material & Technical Data
Steel type: Weathering steel (Corten A / Corten B or equivalent)
Standards: ASTM A588 / ASTM A242 / EN 10025-5 (S355J2W, S355K2W)
Yield strength: ≥ 355 MPa (EN grade)
Tensile strength: 470–630 MPa
Density: 7.85 g/cm³
Typical service life: 60–100+ years (proper design & drainage)
The alloy composition (Cu, Cr, Ni, P) enables the formation of a dense oxide patina that significantly reduces corrosion rate after stabilization.
Weathering & Patina Formation
Initial oxidation: begins within 2–4 weeks after outdoor exposure
Runoff phase: typically 3–6 months (varies by climate)
Patina stabilization: 12–36 months
Corrosion rate after stabilization:
approx. 0.01–0.03 mm/year, compared to 0.05–0.10 mm/year for conventional carbon steel
Once stabilized, the patina reduces further corrosion by 60–80% versus untreated mild steel.
Available Corten Steel Cladding Profiles
1. Flat Sheets
Thickness: 0.8 – 6.0 mm (architectural façade use)
(up to 50 mm for structural elements)
Standard widths: 1000 / 1250 / 1500 / 2000 / 2500 mm
Standard lengths: 2000 – 6000 mm
Flatness tolerance: ± 2 mm / m
Best suited for cassette façades, rainscreen systems, and feature walls.
2. Corrugated Corten Steel Sheets
Common wave height: 18 mm / 27 mm / 35 mm
Effective cover width: 750 – 1000 mm
Thickness: 0.8 – 2.5 mm
Span capability: up to 1.2 m (depending on profile & load)
Improves rigidity by 30–50% compared to flat sheets of the same thickness.
3. Profiled Sheets (Trapezoidal / V / Wave)
Profile depth: 20 – 75 mm
Thickness: 0.9 – 3.0 mm
Application: façades, industrial walls, architectural screens
Provides higher moment of inertia and improved wind-load resistance.
4. Vertical Corten Panels
Panel width: 300 – 600 mm
Panel length: up to 6000 mm
Fixing: concealed or face-fixed systems
Typical thickness: 2.0 – 3.0 mm
Common in modern façade systems emphasizing vertical rhythm.
5. Custom Profiles
Laser cutting tolerance: ± 0.2 mm
Bending radius: ≥ 1.5 × material thickness
Maximum single panel size: 6000 × 2000 mm
Used for signature architecture and bespoke façade designs.
6. Perforated Corten Steel Sheets
Hole diameter: 1.5 – 20 mm
Open area: 10% – 60% (perforated)
up to 80% (woven mesh)
Thickness: 1.2 – 4.0 mm
Supports airflow, solar shading, and acoustic diffusion.
7. Folded & Edge-Formed Panels
Fold depth: up to 100 mm
Angle tolerance: ± 1°
Purpose: edge reinforcement, cassette systems, transitions
Key Performance Features
Maintenance requirement: none (no repainting every 3–5 years)
Coating thickness saved: ~ 80–120 μm vs painted steel
Fire performance: A1 non-combustible
Thermal stability: service temperature up to 425°C
Recyclability: 100%
Lifecycle Cost Advantage
| Material | Initial Cost | Maintenance (30 yrs) | Total Lifecycle Cost |
|---|---|---|---|
| Painted steel | Low | High (repaint every 5–7 yrs) | High |
| Aluminum panels | Medium | Medium | Medium |
| Corten steel siding | Medium–High | Near zero | Lowest |
Why Architects & Developers Specify Corten Steel Siding
Measurable Structural Strength (≥355 MPa Yield Strength)
Corten steel siding is manufactured from weathering steel grades such as EN 10025-5 S355J2W / S355K2W or ASTM A588, offering a minimum yield strength of 355 MPa.
This high mechanical strength allows:
Larger panel sizes with reduced risk of deformation
Improved resistance to wind loads and impact forces
Thinner material usage compared to conventional carbon steel, helping optimize structural weight
For façade systems, this translates into greater design flexibility, fewer substructures, and reliable long-term performance under demanding environmental conditions.
Predictable Corrosion Behavior After Patina Stabilization
Unlike ordinary carbon steel, Corten steel is alloyed with copper, chromium, nickel, and phosphorus, which enables the formation of a dense, self-sealing oxide layer.
Initial oxidation occurs within weeks of exposure
A stable patina typically forms within 12–36 months
After stabilization, the corrosion rate drops to approximately 0.01–0.03 mm per year, up to 70–80% lower than untreated mild steel
This predictable weathering behavior allows architects and developers to confidently specify the material without relying on coatings, while maintaining control over appearance and durability throughout the building lifecycle.
Long Service Life Without Coating Systems
Corten steel siding is designed for bare, unpainted exterior use, eliminating the need for:
Paint systems
Galvanizing
Periodic recoating or surface repairs
By removing coating layers that typically fail after 5–10 years, Corten steel significantly reduces long-term maintenance costs and downtime.
With proper detailing (drainage, ventilation, and isolation from standing water), façade systems can achieve a service life exceeding 60 years, even in challenging climates.
Fully Recyclable and LEED-Friendly Material Choice
Corten steel siding is manufactured from 100% recyclable steel, supporting circular construction principles.
No chemical coatings or surface treatments required
Reduced VOC emissions compared to painted systems
Long lifespan minimizes material replacement and waste
These characteristics contribute positively to LEED, BREEAM, and other green building certifications, making Corten steel an environmentally responsible solution for sustainable architectural projects.
High Design Freedom with Controlled Fabrication Tolerances
Corten steel can be precisely processed using laser cutting, CNC bending, and profiling technologies:
Laser cutting tolerance: ±0.2 mm
Consistent bending accuracy and repeatability
Support for flat panels, folded cassettes, perforated screens, corrugated and profiled sheets
This high level of fabrication control enables architects to realize complex geometries, clean façade lines, and bespoke panel systems, while ensuring repeatable quality during large-scale production and installation.
Is Corten steel cladding expensive?
To provide a ballpark figure for your budgeting, we frequently advise our clients to budget between $600 and $1,200 per tonne for Corten steel.
What is the lifespan of Corten steel?
To tell you frankly, Corten Steel's lifespan can reach up to several decades and, in some cases, even beyond a century, around 40-120 years! Yep, you heard it right – Corten Steel is no one-hit wonder. Its durability is a testament to its unique composition and the formation of that protective rust-like patina.
What is the problem with Corten steel?
Staining Issues: One of the most significant aesthetic drawbacks is the tendency of Corten steel to stain surrounding surfaces. As it weathers, it can leak rust runoff that discolors nearby materials such as concrete or wood, creating rust marks that are difficult to remove.
How thick should Corten steel be?
Thickness: Corten Steel thicknesses of modest specification [2.0mm or 3.0mm] are perfectly fit-for-purpose for + 25 years longevity, in most environments / applications. For + 40 years longevity, an additional 1.0mm thickness should be added, to mitigate the forecast material loss.
What is the weakness of corten steel?
Susceptibility to rusting through when exposed to moisture for long periods. Corten steel tends to rust quickly if exposed to moisture for a long time.
