What is S250GD galvanized steel?
S250GD is the second structural grade of EN 10346 and the one that matches what a normal galvanizing line produces from low-carbon strip without special alloying: yield 250 MPa minimum (typically 280–330), tensile 330 MPa minimum, 19 % elongation, bend radius 0.5 × t. That makes it the default strip for products sold with a load or span table — trapezoidal roofing sheet, sinusoidal sheet, light C/Z purlins, cable trays, framing studs, racking uprights and shelving — because EN 1993-1-3 needs a guaranteed yield and 250 MPa is enough for most spans up to 2–3 m. It is produced from hot- or cold-rolled substrate with Z100–Z275 (Z350 on order), normal or minimised spangle, surface A or B. In Turkey S250GD and S280GD are the volume purlin and roofing grades, which is why we stock S250GD in the roofing thicknesses (0.40–0.70 mm) and the profile thicknesses (1.0–3.0 mm) and slit it to width on our own line.
Chemical composition
| Element | C | Si | Mn | P | S |
|---|---|---|---|---|---|
| max. % (ladle) | 0.20 | 0.60 | 1.70 | 0.10 | 0.045 |
Typical heat: C 0.06–0.09, Mn 0.35–0.60.
Mechanical properties
| Property | Requirement | Typical value | Note |
|---|---|---|---|
| Yield strength ReH / Rp0.2 | ≥ 250 MPa | 280–330 MPa | fyb = 250 |
| Tensile strength Rm | ≥ 330 MPa | 360–420 MPa | |
| Elongation A80 | ≥ 19 % | 24–30 % | |
| Bend radius (180°) | 0.5 × t | passes |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| EN 10147 (old) | S250GD+Z (Fe E 250 G) | withdrawn |
| ASTM A653 | SS Grade 37 (255 MPa) | Structural Steel |
| JIS G3302 | SGC400 | |
| GB/T 2518 | S250GD+Z | |
| EN 10346 | S280GD / S320GD | upward substitutes |
Coating for purlins and roll-formed framing
| Class | Zinc mass (g/m², both sides) | Thickness per side (µm) | Typical life C3 | Where used |
|---|---|---|---|---|
| Z140 | 140 | ≈ 10 | 6–9 years | purlins inside a clad, heated building |
| Z200 | 200 | ≈ 14 | 9–13 years | general C and Z purlins, inland |
| Z275 | 275 | ≈ 20 | 12–18 years | the export default for purlins and rails |
| Z350 | 350 | ≈ 25 | 15–22 years | agricultural buildings, coastal sites |
A purlin is cut, punched and often site-drilled, so the coating is broken at every hole and end. Zinc protects those edges sacrificially up to about 3 mm of exposed steel, which is why a heavier class buys more at the cut than the flat-sheet life table suggests. Touch-up paint on site is a cosmetic measure, not a substitute.
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 0.40–0.70 mm | coil 1 000 / 1 250 mm (roofing widths) | stock Z140 and Z275 |
| 0.80–1.20 mm | coil 1 000 / 1 250 / 1 500 mm | stock Z140; Z275 5–8 days |
| 1.5–3.0 mm | coil 1 250 / 1 500 mm | stock Z140, limited Z275 |
| slit strip | 20–1 500 mm | slitting in Dilovası 3–5 days |
Weight per m² and per sheet
| Thickness | kg/m² | 1 000 × 2 000 (kg) | 1 250 × 2 500 (kg) | 1 500 × 3 000 (kg) |
|---|---|---|---|---|
| 0.4 mm | 3.42 | 6.8 | 10.7 | 15.4 |
| 0.5 mm | 4.20 | 8.4 | 13.1 | 18.9 |
| 0.6 mm | 4.99 | 10.0 | 15.6 | 22.4 |
| 0.7 mm | 5.77 | 11.5 | 18.0 | 26.0 |
| 0.8 mm | 6.56 | 13.1 | 20.5 | 29.5 |
| 1 mm | 8.13 | 16.3 | 25.4 | 36.6 |
| 1.2 mm | 9.70 | 19.4 | 30.3 | 43.6 |
| 1.5 mm | 12.05 | 24.1 | 37.7 | 54.2 |
| 2 mm | 15.98 | 32.0 | 49.9 | 71.9 |
| 2.5 mm | 19.90 | 39.8 | 62.2 | 89.6 |
| 3 mm | 23.83 | 47.7 | 74.5 | 107.2 |
Includes Z275 coating; subtract 0.135 kg/m² for Z140.
Forming, welding and design
Roll-forms into trapezoidal, sinusoidal, C, Z, sigma and omega profiles on standard tooling; brake-press bends at 0.5 × t; spring-back a few degrees more than DX51D. Screw, rivet, clinch or spot-weld; MAG with fume extraction and zinc-rich touch-up. Design to EN 1993-1-3 with fyb = 250 MPa, fu = 330 MPa, core thickness = nominal − zinc (Z275 ≈ 0.04 mm). Cut-to-length and slitting on our lines; profile drawings for our own roll-forming are welcome.
Where it is used
- Trapezoidal and sinusoidal roofing and cladding sheet with span tables
- Light C and Z purlins, side rails (t ≤ 2 mm)
- Cable trays, ladders and support systems
- Light-gauge framing studs, tracks and joists
- Racking uprights, shelving and mezzanine decking
- Greenhouse, fencing and agricultural profiles
S250GD vs S280GD vs S350GD
All three are structural galvanized strip with the same zinc; the number is the guaranteed yield. S250GD is the roofing and light-profile grade; S280GD is the purlin standard for 1.5–2.5 mm C/Z sections; S350GD is the high-strength grade for long-span purlins, decking and solar structures. Higher grades are harder to form and a few dollars dearer per ton, so order the lowest grade the design allows — and check the span table, which is where the grade actually pays off.
Price
S250GD carries about 10 USD/t over DX51D of the same thickness; the bands below are indicative FOB Istanbul by thickness for our stock. Slitting and cut-to-length priced per ton.
Bands from our weekly export list (September 2026), FOB Istanbul, full-container quantities, excluding freight and certificates. Firm price per project on RFQ within one working day.
Export and packing
Roofing-width S250GD is kept in 1 000 and 1 250 mm coils and ships from stock the same week. Coils are cradled eye-to-sky with VCI wrap and four straps; slit strip for purlin lines is delivered in matched sets with the width and coil number on each band. Loading is 20-21 t per 20' and 24-25 t per 40' HC. Tariff 7210.49.
| Term | Detail |
|---|---|
| MOQ | One coil (5–20 t) or 5 t of sheet |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | Stock 0.40–3.0 mm Z140/Z275: 3–5 working days; slit strips 5–8 days |
| Packing | Coil eye-to-sky, VCI wrap; slit coils on pallets; sheet on skids |
| Container / truck | 20' one coil ≤ 20 t; 40' HC two coils or 24 t sheet |
| Documents | Invoice, packing list, EN 10204 3.1 (3.2 on request), certificate of origin; SASO / SONCAP / PVoC on request |
| Payment | 30% advance, balance against B/L copy; L/C at sight for orders above 100 t |
Certificates and testing
Each S250GD coil is released with an EN 10204 3.1 certificate: heat number, ladle analysis, yield, tensile, elongation and the triple-spot zinc mass. Roofing contractors usually also want the coating thickness measured on the finished profile, which we do on our own roll-forming lines and report with the delivery note.
How to order
Specify thickness × width (or slit widths), coating (Z140 / Z275), spangle, surface, treatment, coil weight limit and tonnage; roofing-width coils (1 000 / 1 250) ship from stock.
Standards
- EN 10346:2015 — S250GD+Z, 1.0242
- EN 10143 — tolerances
- EN 1993-1-3 — cold-formed design (fyb = 250 MPa)
- EN 10204 3.1
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: S250GD · S280GD · S350GD
Frequently asked questions
What is S250GD steel?
A structural hot-dip galvanized steel to EN 10346 (1.0242) with guaranteed yield ≥ 250 MPa and tensile ≥ 330 MPa — the standard strip for roofing sheet, light purlins, cable trays and framing profiles.
What does S250GD+Z275 mean?
S250GD grade with 275 g/m² zinc (both sides), about 20 µm per side — the export and outdoor standard; Z140 is the Turkish stock standard.
What is the difference between S250GD and S350GD?
Guaranteed yield 250 vs 350 MPa; S350GD allows longer purlin spans and thinner decking but is harder to form and costs more. Same zinc coatings.
What is the ASTM equivalent of S250GD?
ASTM A653 SS Grade 37 (255 MPa yield); JIS G3302 SGC400.
Is S250GD in stock in Turkey?
Yes — 0.40–3.0 mm in 1 000–1 500 mm widths with Z140 and Z275 at our Dilovası warehouse; slit widths in 3–5 days.