HE 300 B vs UC 254×254×132
HE 300 B is an HE section from the European (Continental) range; UC 254×254×132 is the closest equivalent in the UK Blue Book (SCI P363). They are close to interchangeable in bending: 1870 cm³ against 1870 cm³ of plastic modulus, a difference of 0.0%. HE 300 B is the lighter of the two at 117 kg/m against 132 kg/m, a saving of 11.4% on steel weight. HE 300 B is deeper, 300 mm against 276.3 mm, which matters where the floor zone is tight.
| Property | HE 300 B HE | UC 254×254×132 UC | Difference |
|---|---|---|---|
| Mass | 117 kg/m | 132 kg/m | -11.4% |
| Depth | 300 mm | 276.3 mm | +8.6% |
| Width | 300 mm | 261.3 mm | +14.8% |
| Web thickness | 11 mm | 15.3 mm | -28.1% |
| Flange thickness | 19 mm | 25.3 mm | -24.9% |
| Area | 149 cm² | 168 cm² | -11.3% |
| Second moment, major (Iy) | 25,200 cm⁴ | 22,500 cm⁴ | +12.0% |
| Plastic modulus, major (Wpl,y) | 1,870 cm³ | 1,870 cm³ | same |
| Elastic modulus, major (Wel,y) | 1,680 cm³ | 1,630 cm³ | +3.1% |
| Second moment, minor (Iz) | 8,560 cm⁴ | 7,530 cm⁴ | +13.7% |
| Plastic modulus, minor (Wpl,z) | 870 cm³ | 878 cm³ | -0.9% |
| Radius of gyration, minor (iz) | 7.58 cm | 6.69 cm | +13.3% |
| Torsion constant (It) | 189 cm⁴ | 319 cm⁴ | -40.8% |
HE 300 B to EN 10365 · Continental Steel; UC 254×254×132 to BS EN 10365:2017. Difference is expressed relative to UC 254×254×132.
How to choose between them
On stiffness, HE 300 B has the larger second moment of area: 25,200 cm⁴ against 22,500 cm⁴, a difference of 12.0%. 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, HE 300 B is the more efficient section: 16.0 against 14.2 cm³ per kg/m, 12.8% 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. HE sections are specified to EN 10365 · Continental Steel and UC to BS EN 10365:2017; 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 11.4% weight.
In short, UC 254×254×132 is the stronger section and HE 300 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.