Tee 152×229×34 vs WT 9X25
Tee 152×229×34 is an Tees (from UB) section from the UK Blue Book (SCI P363); WT 9X25 is the closest equivalent in the American AISC Shapes Database. They are close to interchangeable in bending: 223 cm³ against 226.14 cm³ of plastic modulus, a difference of 1.4%. Tee 152×229×34 is the lighter of the two at 33.6 kg/m against 37.2 kg/m, a saving of 9.7% on steel weight. Both are about 229 mm deep, so either fits the same construction zone.
| Property | Tee 152×229×34 Tees (from UB) | WT 9X25 WT | Difference |
|---|---|---|---|
| Mass | 33.6 kg/m | 37.2 kg/m | -9.7% |
| Depth | 228.9 mm | 228.6 mm | +0.1% |
| Width | 153.8 mm | 190.5 mm | -19.3% |
| Web thickness | 9 mm | 9 mm | same |
| Flange thickness | 15 mm | 14.5 mm | +3.4% |
| Area | 42.8 cm² | 47.4 cm² | -9.7% |
| Second moment, major (Iy) | 2,120 cm⁴ | 2,227 cm⁴ | -4.8% |
| Plastic modulus, major (Wpl,y) | 223 cm³ | 226.14 cm³ | -1.4% |
| Elastic modulus, major (Wel,y) | 125 cm³ | 127.66 cm³ | -2.1% |
| Second moment, minor (Iz) | 456 cm⁴ | 832.5 cm⁴ | -45.2% |
| Plastic modulus, minor (Wpl,z) | 93.3 cm³ | 135.68 cm³ | -31.2% |
| Radius of gyration, minor (iz) | 3.27 cm | 4.19 cm | -22.0% |
| Torsion constant (It) | 23.8 cm⁴ | 25.76 cm⁴ | -7.6% |
Tee 152×229×34 to BS EN 10365:2017; WT 9X25 to AISC Shapes Database v16.0. Difference is expressed relative to WT 9X25.
How to choose between them
On stiffness, WT 9X25 has the larger second moment of area: 2,227 cm⁴ against 2,120 cm⁴, a difference of 4.8%. 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, Tee 152×229×34 is the more efficient section: 6.6 against 6.1 cm³ per kg/m, 9.2% 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: WT 9X25 has 135.68 cm³ of minor-axis plastic modulus against 93.3 cm³, 31.2% 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. Tees (from UB) sections are specified to BS EN 10365:2017 and WT to AISC Shapes Database v16.0; 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 9.7% weight.
In short, WT 9X25 is the stronger section and Tee 152×229×34 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.