A detailed comparison for the common "galvanized or painted?" question in building projects — durability, corrosion resistance, cost and application areas.
One of the most common dilemmas in roofing and façade projects is: galvanized steel or painted steel? Although these two products look similar in appearance and application, they offer different profiles in terms of corrosion resistance, life expectancy and cost. In this article we compare both products in detail and explain which one to prefer in which situation.
Definitions: How Do They Actually Differ?
Galvanized steel is cold-rolled steel sheet coated with zinc, either by immersion in a molten zinc bath (hot-dip galvanizing) or by an electrolytic method. Standard coating weights are Z140 (140 g/m² per side) or Z275 (275 g/m² per side).
Painted steel is produced by applying primer and topcoat paint layers onto galvanized steel under factory conditions. In other words, painted steel is essentially a galvanized steel + paint layer combination. For this reason the TS EN 10169 standard requires a galvanized substrate at the base of painted steel.
Comparison Table
| Criterion | Galvanized Steel | Painted Steel |
|---|---|---|
| Corrosion Resistance | 10–20 years (depending on atmosphere) | 15–25+ years |
| Color Options | Zinc-silver only | 200+ RAL colors |
| Standard | TS EN 10346 | TS EN 10169 |
| Unit Cost | More economical | 15–25% more expensive |
| Aesthetics | Industrial / functional | Architectural / decorative |
| Maintenance | May need repainting after 10 years | Maintenance-free for 20+ years |
| UV Resistance | Not directly affected | Depends on paint quality |
Advantages of Galvanized Steel
- Cost advantage: Unit price per m² is 15–25% lower than painted steel
- Industrial look: The plain appearance preferred in structures such as factories, warehouses and workshops
- Easy to weld: The zinc layer does not prevent welding (with painted steel the coating must be stripped)
- Wide thickness range: Standard production from 0.30 mm to 3 mm
Advantages of Painted Steel
- Superior corrosion resistance: The galvanized substrate + paint combination provides a much longer life than zinc alone
- Aesthetic freedom: Production in any color from the RAL catalog — ideal for corporate identity or architectural decoration
- UV and weather resistance: Polyester or PVC plastisol coating acts as armor against sun and rain
- Low reflection: No glaring shine like galvanized steel — preferred in residential areas
Which One to Choose in Which Situation?
Choose Galvanized Steel When:
- Building industrial warehouses, factories, barns or garages
- Using short- to medium-term (5–10 years) temporary structures
- Building structures that will later be painted (as a base substrate)
- Welded fabrication is required
Choose Painted Steel When:
- Cladding homes, villas and social areas
- Working in coastal regions (for sea-salt corrosion)
- Architectural / aesthetic concerns are a priority
- Building long-term (20+ year) structures
- Building commercial structures that require brand identity (color matching)
Cost Analysis: Which Is More Profitable in the Long Run?
Although galvanized steel appears advantageous in terms of initial investment cost, painted steel is usually more economical when the 20-year total cost of ownership (TCO) is calculated. This is because:
- Galvanized steel takes on a matte appearance after 8–12 years and loses its aesthetic quality
- If painting is needed after corrosion begins, an additional cost of 80–150 TL per m² arises
- Thanks to paint applied under factory conditions, painted steel provides a coating 3–5× more durable than field application
Conclusion
Galvanized and painted steel are not so much "alternatives to each other" as two complementary products that answer different needs. Galvanized is the right choice for industrial and functional projects; painted steel is the right choice for projects where aesthetics, longevity and architectural value are desired.
As Murat Tiritoğlu A.Ş., we supply from stock the full range of both galvanized steel (TS EN 10346 certified) and painted steel (TS EN 10169 certified, polyester and PVC plastisol coating) in a wide range of sizes and colors. Browse our RAL color catalog or get in touch for a quote.