W 14X90 vs H-350x350x12x19-137
W 14X90 is an W section from the American AISC Shapes Database; H-350x350x12x19-137 is the closest equivalent in the European (Continental) range. They are close to interchangeable in bending: 2572.8 cm³ against 2545 cm³ of plastic modulus, a difference of 1.1%. W 14X90 is the lighter of the two at 133.9 kg/m against 137 kg/m, a saving of 2.3% on steel weight. Both are about 353 mm deep, so either fits the same construction zone.
| Property | W 14X90 W | H-350x350x12x19-137 MB & MC | Difference |
|---|---|---|---|
| Mass | 133.9 kg/m | 137 kg/m | -2.3% |
| Depth | 355.6 mm | 350 mm | +1.6% |
| Width | 368.3 mm | 350 mm | +5.2% |
| Web thickness | 11.2 mm | 12 mm | -6.7% |
| Flange thickness | 18 mm | 19 mm | -5.3% |
| Area | 171 cm² | 174 cm² | -1.7% |
| Second moment, major (Iy) | 41,582 cm⁴ | 40,300 cm⁴ | +3.2% |
| Plastic modulus, major (Wpl,y) | 2,572.8 cm³ | 2,545 cm³ | +1.1% |
| Elastic modulus, major (Wel,y) | 2,343.4 cm³ | 2,303 cm³ | +1.8% |
| Second moment, minor (Iz) | 15,068 cm⁴ | 13,590 cm⁴ | +10.9% |
| Plastic modulus, minor (Wpl,z) | 1,238.9 cm³ | 1,179 cm³ | +5.1% |
| Radius of gyration, minor (iz) | 9.4 cm | 8.84 cm | +6.3% |
| Torsion constant (It) | 169 cm⁴ | 199 cm⁴ | -15.1% |
W 14X90 to AISC Shapes Database v16.0; H-350x350x12x19-137 to Continental Steel. Difference is expressed relative to H-350x350x12x19-137.
How to choose between them
On stiffness, W 14X90 has the larger second moment of area: 41,582 cm⁴ against 40,300 cm⁴, a difference of 3.2%. This matters more often than the strength comparison, because on normal floor spans deflection rather than bending capacity sets the beam size - so if the two are close on modulus but apart on inertia, the stiffer one is usually the better answer even when it is not the stronger one.
Measured as bending capacity per kilogram of steel, W 14X90 is the more efficient section: 19.2 against 18.6 cm³ per kg/m, 3.4% better. Over a floor of repeated beams that difference is real tonnage, though it is often outweighed by whichever section the fabricator can actually source.
These come from different catalogues, so treat the swap as a design change rather than a like-for-like substitution. W sections are specified to AISC Shapes Database v16.0 and MB & MC to Continental Steel; the steel grades, tolerances and available lengths differ, connection details and bolt gauges are set out differently, and the two are rarely both stocked in the same market. Check availability before changing a section on a drawing to save 2.3% weight.
In short, W 14X90 is the stronger section and W 14X90 is the lighter one; where those are the same section, it is the clear choice, and where they are not, decide on whether your design is governed by capacity or by tonnage.