The headline ranges
For early-stage estimating, here's what we see in practice on Turkish industrial sites:
- Light single-storey warehouse, 20–25 m span, no crane: 25–35 kg/m²
- Medium warehouse, 30 m span, light crane (5–10 t): 35–45 kg/m²
- Heavy warehouse, 30+ m span, 25 t+ overhead crane: 50–70 kg/m²
- Multi-storey logistics or VNA warehouse: 70–110 kg/m²
- Aircraft hangar, 40+ m span, heavy snow: 60–95 kg/m²
What drives tonnage up
- Span. Doubling the span more than doubles the steel — bending moment grows with span².
- Height to eaves. Taller columns mean bigger columns. Above 12 m you start to see real cost increase.
- Snow load. Northern Turkey, mountain regions and Eastern Anatolia carry 1.0–1.5 kN/m². Coastal Aegean and Mediterranean: 0.5–0.8 kN/m².
- Wind loads. Coastal sites, especially Çanakkale and the Aegean, drive bracing systems heavier.
- Crane loads. A single 25 t crane on a 30 m span can add 30–40% to column and runway-beam tonnage.
- Seismic zone. Turkey's seismic map varies 2–5×; high-zone sites need more bracing.
What drives tonnage down
- Modular column spacing (8–12 m bays — sweet spot)
- Lattice trusses instead of solid-web girders for very long spans
- Rigid frames that share work between columns and beams
- Tapered haunches at column-to-rafter connections
- High-strength steel (S355 instead of S235) — about 20% less weight for same capacity
Worked example
A typical project we recently completed: 8,500 m² automated warehouse, 26 m clear span, 14 m to underside of trusses, 0.85 kN/m² snow, no crane. Final tonnage: 360 t. That's 42 kg/m² — squarely in the medium-warehouse range.
The honest caveat
These numbers are for early-stage budgeting. The real number comes from a static analysis based on actual drawings, site location, crane plan and specific load cases. Send us your project and we'll give you a tonnage take-off within a week.