Home › Resources › Galvanized Steel Coating Guide (Z275 Explained)
Steel Knowledge · Wholesale & Export
Galvanized Steel Coating Guide
Zinc coating class controls how long galvanized steel lasts. Here is what the Z numbers mean.
| Coating | Zinc mass (both sides) | Typical use |
|---|---|---|
| Z80 | 80 g/m² | Indoor / light |
| Z140 | 140 g/m² | General |
| Z180 | 180 g/m² | Roofing/cladding |
| Z275 | 275 g/m² | Outdoor / durable |
The Z number is the total zinc mass in g/m² across both surfaces — higher = longer life. Z275 is the common outdoor spec for roofing and purlins. We supply galvanized coil Z80–Z275 and PPGI. Compare GI vs PPGI.
Frequently asked questions
What does Z275 mean?
A zinc coating mass of 275 g/m² over both surfaces of the sheet — a durable outdoor-grade galvanizing.
Which coating for roofing?
Z180–Z275 is typical for roofing and cladding; PPGI over Z-coating adds further life and colour.
Is heavier zinc always better?
It lasts longer but costs more and can affect forming — match the coating to the environment.
Need mill-certified steel in bulk?
Steel Pro Rebar Germany Gmbh exports structural steel, rebar, coil, plate and sections worldwide with EN 10204 3.1 MTCs.
Request a bulk quote →WhatsApp: +49 163 1141934