W 27X281 vs HE 700 x 418
W 27X281 is an W section from the American AISC Shapes Database; HE 700 x 418 is the closest equivalent in the European (Continental) range. W 27X281 carries more bending: 15338.3 cm³ of plastic modulus against 14800 cm³, 3.6% more. They weigh essentially the same, 418.2 kg/m and 418 kg/m. Both are about 744 mm deep, so either fits the same construction zone.
| Property | W 27X281 W | HE 700 x 418 HE | Difference |
|---|---|---|---|
| Mass | 418.2 kg/m | 418 kg/m | same |
| Depth | 744.2 mm | 744 mm | same |
| Width | 365.8 mm | 313 mm | +16.9% |
| Web thickness | 26.9 mm | 29.5 mm | -8.8% |
| Flange thickness | 49 mm | 54 mm | -9.3% |
| Area | 536.1 cm² | 532 cm² | +0.8% |
| Second moment, major (Iy) | 495,315 cm⁴ | 472,000 cm⁴ | +4.9% |
| Plastic modulus, major (Wpl,y) | 15,338.3 cm³ | 14,800 cm³ | +3.6% |
| Elastic modulus, major (Wel,y) | 13,339.1 cm³ | 12,700 cm³ | +5.0% |
| Second moment, minor (Iz) | 39,667 cm⁴ | 27,800 cm⁴ | +42.7% |
| Plastic modulus, minor (Wpl,z) | 3,375.7 cm³ | 2,800 cm³ | +20.6% |
| Radius of gyration, minor (iz) | 8.61 cm | 7.22 cm | +19.3% |
| Torsion constant (It) | 3,309 cm⁴ | 3,960 cm⁴ | -16.4% |
W 27X281 to AISC Shapes Database v16.0; HE 700 x 418 to EN 10365 · Continental Steel. Difference is expressed relative to HE 700 x 418.
How to choose between them
On stiffness, W 27X281 has the larger second moment of area: 495,315 cm⁴ against 472,000 cm⁴, a difference of 4.9%. 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 of steel, W 27X281 is the more efficient section: 36.7 against 35.4 cm³ per kg/m, 3.6% 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.
The two diverge much more about the minor axis: W 27X281 has 3375.7 cm³ of minor-axis plastic modulus against 2800 cm³, 20.6% 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 a marginal amount of weight.
In short, W 27X281 is the stronger section and HE 700 x 418 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.