UB 457×152×67 vs IPE A 450
UB 457×152×67 is an UB section from the UK Blue Book (SCI P363); IPE A 450 is the closest equivalent in the European (Continental) range. IPE A 450 carries more bending: 1490 cm³ of plastic modulus against 1450 cm³, 2.7% more. They weigh essentially the same, 67.2 kg/m and 67.2 kg/m. UB 457×152×67 is deeper, 458 mm against 447 mm, which matters where the floor zone is tight.
| Property | UB 457×152×67 UB | IPE A 450 IPE | Difference |
|---|---|---|---|
| Mass | 67.2 kg/m | 67.2 kg/m | same |
| Depth | 458 mm | 447 mm | +2.5% |
| Width | 153.8 mm | 190 mm | -19.1% |
| Web thickness | 9 mm | 7.6 mm | +18.4% |
| Flange thickness | 15 mm | 13.1 mm | +14.5% |
| Area | 85.6 cm² | 85.6 cm² | same |
| Second moment, major (Iy) | 28,900 cm⁴ | 29,800 cm⁴ | -3.0% |
| Plastic modulus, major (Wpl,y) | 1,450 cm³ | 1,490 cm³ | -2.7% |
| Elastic modulus, major (Wel,y) | 1,260 cm³ | 1,330 cm³ | -5.3% |
| Second moment, minor (Iz) | 913 cm⁴ | 1,500 cm⁴ | -39.1% |
| Plastic modulus, minor (Wpl,z) | 187 cm³ | 246 cm³ | -24.0% |
| Radius of gyration, minor (iz) | 3.27 cm | 4.19 cm | -22.0% |
| Torsion constant (It) | 47.7 cm⁴ | 47.1 cm⁴ | +1.3% |
UB 457×152×67 to BS EN 10365:2017; IPE A 450 to EN 10365 · Continental Steel. Difference is expressed relative to IPE A 450.
How to choose between them
On stiffness, IPE A 450 has the larger second moment of area: 29,800 cm⁴ against 28,900 cm⁴, a difference of 3.0%. 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, IPE A 450 is the more efficient section: 22.2 against 21.6 cm³ per kg/m, 2.7% 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: IPE A 450 has 246 cm³ of minor-axis plastic modulus against 187 cm³, 24.0% 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. UB sections are specified to BS EN 10365:2017 and IPE 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, IPE A 450 is the stronger section and IPE A 450 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.