EN 10346

EN 10346, Continuously hot-dip coated steel flat products for cold forming – Technical delivery conditions, is the European Standard for metallic-coated steel sheet and strip. It is the base specification for most steel roofing, wall cladding and rainwater products made in Europe, whether supplied bare or with an organic (paint) coating.

Editions

The 2015 edition replaced EN 10346:2009. CEN records show EN 10346:2015 revised by EN 10346:2026, with withdrawal of the 2015 edition effective in October 2026. National versions (such as BS EN 10346 and DIN EN 10346) follow the CEN edition.

Coating types

The standard covers several metallic coatings, each with its own code:

• Z – zinc (galvanized)
• ZF – zinc-iron alloy (galvannealed)
• ZA – zinc-aluminium alloy
• AZ – aluminium-zinc alloy (the 55% Al type sold as Galvalume or Aluzinc)
• AS – aluminium-silicon alloy
• ZM – zinc-magnesium alloy

Coating mass is written after the code in grams per square metre, total for both sides (for example Z275 or AZ185). Steel grades for forming and structural uses are specified separately in the standard.

Use in roofing

Profiled steel sheets, standing seam panels, steel tiles and rainwater systems in Europe are typically made from EN 10346 substrate. Pre-painted products add an organic coating on top of the metallic layer, and finished roofing sheets are assessed against separate European product standards for metal roofing. Zinc-magnesium coatings have grown in use because they offer good corrosion resistance at lower coating masses.

Comparison with North America

• ASTM A653 covers zinc and zinc-iron coated sheet.
• ASTM A792 covers 55% aluminum-zinc coated sheet.

North American designations use different units (ounces per square foot), so coating masses must be converted rather than compared by number.