RHS 260×140×16 vs RHS 250×150×16
RHS 260×140×16 is an RHS Hot-finished section from the UK Blue Book (SCI P363); RHS 250×150×16 is the closest equivalent in the European (Continental) range. RHS 260×140×16 carries more bending: 925 cm³ of plastic modulus against 906 cm³, 2.1% more. They weigh essentially the same, 90.3 kg/m and 91.5 kg/m. RHS 260×140×16 is deeper, 260 mm against 250 mm, which matters where the floor zone is tight.
| Property | RHS 260×140×16 RHS Hot-finished | RHS 250×150×16 RHS | Difference |
|---|---|---|---|
| Mass | 90.3 kg/m | 91.5 kg/m | -1.3% |
| Depth | 260 mm | 250 mm | +4.0% |
| Width | 140 mm | 150 mm | -6.7% |
| Web thickness | 0 mm | 0 mm | same |
| Flange thickness | 0 mm | 0 mm | same |
| Area | 115 cm² | 115 cm² | same |
| Second moment, major (Iy) | 9,340 cm⁴ | 8,879 cm⁴ | +5.2% |
| Plastic modulus, major (Wpl,y) | 925 cm³ | 906 cm³ | +2.1% |
| Elastic modulus, major (Wel,y) | 718 cm³ | 710 cm³ | +1.1% |
| Second moment, minor (Iz) | 3,400 cm⁴ | 3,873 cm⁴ | -12.2% |
| Plastic modulus, minor (Wpl,z) | 588 cm³ | 625 cm³ | -5.9% |
| Radius of gyration, minor (iz) | 5.44 cm | 5.8 cm | -6.2% |
| Torsion constant (It) | 8,260 cm⁴ | 8,868 cm⁴ | -6.9% |
RHS 260×140×16 to BS EN 10210-2:2006; RHS 250×150×16 to EN 10219 · Continental Steel. Difference is expressed relative to RHS 250×150×16.
How to choose between them
On stiffness, RHS 260×140×16 has the larger second moment of area: 9,340 cm⁴ against 8,879 cm⁴, a difference of 5.2%. 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, RHS 260×140×16 is the more efficient section: 10.2 against 9.9 cm³ per kg/m, 3.5% 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. RHS Hot-finished sections are specified to BS EN 10210-2:2006 and RHS to EN 10219 · 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, RHS 260×140×16 is the stronger section and RHS 260×140×16 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.