The Fundamental Difference: Coating Chemistry
Molecular Protection Mechanisms:
Protection Timeline Comparison:
| Exposure Time | Galvanized (G90) | SKW AZ150 | Advantage |
|---|---|---|---|
| 2 Years | 0% rust | 0% rust | Equal |
| 5 Years | 12% surface rust | 0% rust | 12X |
| 10 Years | Perforation | 3% rust | 6X |
| 15 Years | Full failure | 8% rust | Infinite |
Laboratory Proof: Salt Spray Testing
ASTM B117 Accelerated Corrosion Test:
Real-World Equivalency:
| Environment | Galvanized Failure | AZ150 Failure | Life Extension |
|---|---|---|---|
| Coastal | 5-7 years | 20-25 years | 4X |
| Industrial | 6-8 years | 18-22 years | 3X |
| Rural | 10-12 years | 25-30 years | 2.5X |
Visual Identification Guide
Spotting the Difference:
Characteristic Comparison:
| Feature | Galvanized Steel | Aluminum-Zinc Steel |
|---|---|---|
| Surface Pattern | Spangled | Uniform Matte |
| Cut Edge Color | Bright Silver | Grayish-Silver |
| Scratch Test | Bright streak | Dull streak |
| Weight (0.5mm) | 3.75kg/m² | 3.65kg/m² |
The Aluminum Advantage: Barrier Protection
How 55% Aluminum Works:
Performance Enhancement:
| Property | Galvanized | Al-Zn | Improvement |
|---|---|---|---|
| Heat Resistance | 149°C max | 315°C | 2.1X |
| Corrosion Rate | 50 μm/yr | 8.3 μm/yr | 6X |
| UV Degradation | 3 years | 15 years | 5X |
Global Case Studies
Miami Beach Condominium:
- Installed: 2010
- Salt exposure: High
- 2023 inspection:
- Galvanized roofs: 100% replaced
- SKW AZ150 roofs: 94% intact
Cost-Benefit Analysis
Lifecycle Value Calculation:
Savings Breakdown:
| Cost Factor | Galvanized | Al-Zn | Savings |
|---|---|---|---|
| Material (per m²) | $18.50 | $24.80 | – |
| Installation | $11.20 | $11.20 | – |
| 1st Replacement | $29.70 | $0 | $29.70 |
| 2nd Replacement | $32.50 | $0 | $32.50 |
| Total 30-year | $92.90 | $36.00 | $56.90 |
Technical Specifications
SKW‘s Superior Composition:
| Element | Galvanized | SKW AZ150 | Advantage |
|---|---|---|---|
| Aluminum | 0% | 55% | Infinite |
| Zinc | 99% | 43.4% | – |
| Silicon | 0.2% | 1.6% | 8X |
| Coating Weight | 90g/m² | 150g/m² | 67% more |
Certifications:
- ASTM A792 (Galvanized) vs ASTM A755 (Al-Zn)
- EN 10346 Z275 vs EN 10346 DX150D
Installation & Maintenance Advantages
Performance Preservation:
Maintenance Requirements:
| Issue | Galvanized Frequency | SKW Frequency |
|---|---|---|
| Touch-up Painting | Every 3 years | Never |
| Rust Treatment | Every 2 years | Never |
| Coating Inspection | Annual | Quadrennial |
Warranty Comparison
Coverage Difference:
Claim Requirements:
- Galvanized: >10% rust = replacement
- SKW: >30% rust = full replacement
Certifications: ASTM A755 • EN 10346 • ISO 1461 • JIS G3321
Performance Warranty: 25-Year Perforation • 15-Year Finish • 10-Year Edge Protection
SKW’s aluminum-zinc coated stone-coated metal roofs deliver scientifically proven 3-6X longer life than galvanized steel: Laboratory salt spray tests show 6,000 hours to first rust versus 1,000 hours for galvanized, translating to 25+ year service life in coastal environments. Our proprietary 55% aluminum alloy creates a permanent barrier while the zinc component sacrifices itself to protect scratches. With material certification guides, visual identification techniques, and lifecycle cost analysis, we empower you to make informed decisions that protect your investment for decades.