W 14X99 vs HE 360 B
W 14X99 is an W section from the American AISC Shapes Database; HE 360 B is the closest equivalent in the European (Continental) range. W 14X99 carries more bending: 2835 cm³ of plastic modulus against 2680 cm³, 5.8% more. HE 360 B is the lighter of the two at 142 kg/m against 147.3 kg/m, a saving of 3.7% on steel weight. Both are about 360 mm deep, so either fits the same construction zone.
| Property | W 14X99 W | HE 360 B HE | Difference |
|---|---|---|---|
| Mass | 147.3 kg/m | 142 kg/m | +3.7% |
| Depth | 360.7 mm | 360 mm | +0.2% |
| Width | 370.8 mm | 300 mm | +23.6% |
| Web thickness | 12.3 mm | 12.5 mm | -1.6% |
| Flange thickness | 19.8 mm | 22.5 mm | -12.0% |
| Area | 187.7 cm² | 181 cm² | +3.7% |
| Second moment, major (Iy) | 46,202 cm⁴ | 43,200 cm⁴ | +6.9% |
| Plastic modulus, major (Wpl,y) | 2,835 cm³ | 2,680 cm³ | +5.8% |
| Elastic modulus, major (Wel,y) | 2,572.8 cm³ | 2,400 cm³ | +7.2% |
| Second moment, minor (Iz) | 16,733 cm⁴ | 10,100 cm⁴ | +65.7% |
| Plastic modulus, minor (Wpl,z) | 1,370 cm³ | 1,030 cm³ | +33.0% |
| Radius of gyration, minor (iz) | 9.42 cm | 7.49 cm | +25.8% |
| Torsion constant (It) | 223.5 cm⁴ | 298 cm⁴ | -25.0% |
W 14X99 to AISC Shapes Database v16.0; HE 360 B to EN 10365 · Continental Steel. Difference is expressed relative to HE 360 B.
How to choose between them
On stiffness, W 14X99 has the larger second moment of area: 46,202 cm⁴ against 43,200 cm⁴, a difference of 6.9%. 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, the two are equally efficient (19.2 against 18.9 cm³ per kg/m), so on a pure steel-tonnage basis there is nothing to choose between them. The decision comes down to availability, connection detailing and what the rest of the frame uses.
The two diverge much more about the minor axis: W 14X99 has 1370 cm³ of minor-axis plastic modulus against 1030 cm³, 33.0% more. If the member sees any minor-axis bending, or if it is unrestrained over a long length and lateral-torsional buckling governs, that gap decides the comparison even though the major-axis numbers looked equivalent.
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 HE to EN 10365 · 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 3.7% weight.
In short, W 14X99 is the stronger section and HE 360 B 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.