SHS 300×300×14.2 vs SHS 300×300×16
SHS 300×300×14.2 is an SHS Hot-finished section from the UK Blue Book (SCI P363); SHS 300×300×16 is the closest equivalent in the European (Continental) range. SHS 300×300×16 carries more bending: 1774 cm³ of plastic modulus against 1710 cm³, 3.6% more. SHS 300×300×14.2 is the lighter of the two at 126 kg/m against 138 kg/m, a saving of 8.7% on steel weight. Both are about 300 mm deep, so either fits the same construction zone.
| Property | SHS 300×300×14.2 SHS Hot-finished | SHS 300×300×16 SHS Cold-formed | Difference |
|---|---|---|---|
| Mass | 126 kg/m | 138 kg/m | -8.7% |
| Depth | 300 mm | 300 mm | same |
| Width | 300 mm | 300 mm | same |
| Web thickness | 0 mm | 0 mm | same |
| Flange thickness | 0 mm | 0 mm | same |
| Area | 160 cm² | 171 cm² | -6.4% |
| Second moment, major (Iy) | 21,600 cm⁴ | 22,080 cm⁴ | -2.2% |
| Plastic modulus, major (Wpl,y) | 1,710 cm³ | 1,774 cm³ | -3.6% |
| Elastic modulus, major (Wel,y) | 1,440 cm³ | 1,472 cm³ | -2.2% |
| Second moment, minor (Iz) | 21,600 cm⁴ | 22,080 cm⁴ | -2.2% |
| Plastic modulus, minor (Wpl,z) | 1,710 cm³ | 1,774 cm³ | -3.6% |
| Radius of gyration, minor (iz) | 11.6 cm | 11.4 cm | +1.8% |
| Torsion constant (It) | 33,900 cm⁴ | 37,840 cm⁴ | -10.4% |
SHS 300×300×14.2 to BS EN 10210-2:2006; SHS 300×300×16 to EN 10219 · Continental Steel. Difference is expressed relative to SHS 300×300×16.
How to choose between them
On stiffness, SHS 300×300×16 has the larger second moment of area: 22,080 cm⁴ against 21,600 cm⁴, a difference of 2.2%. 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, SHS 300×300×14.2 is the more efficient section: 13.6 against 12.9 cm³ per kg/m, 5.6% 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.
These come from different catalogues, so treat the swap as a design change rather than a like-for-like substitution. SHS Hot-finished sections are specified to BS EN 10210-2:2006 and SHS Cold-formed 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 8.7% weight.
In short, SHS 300×300×16 is the stronger section and SHS 300×300×14.2 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.