IPE 220 vs W 8X18
IPE 220 is an IPE section from the European (Continental) range; W 8X18 is the closest equivalent in the American AISC Shapes Database. IPE 220 carries more bending: 285 cm³ of plastic modulus against 278.58 cm³, 2.3% more. IPE 220 is the lighter of the two at 26.2 kg/m against 26.8 kg/m, a saving of 2.2% on steel weight. IPE 220 is deeper, 220 mm against 206.8 mm, which matters where the floor zone is tight.
| Property | IPE 220 IPE | W 8X18 W | Difference |
|---|---|---|---|
| Mass | 26.2 kg/m | 26.8 kg/m | -2.2% |
| Depth | 220 mm | 206.8 mm | +6.4% |
| Width | 110 mm | 133.4 mm | -17.5% |
| Web thickness | 5.9 mm | 5.8 mm | +1.7% |
| Flange thickness | 9.2 mm | 8.4 mm | +9.5% |
| Area | 33.4 cm² | 33.9 cm² | -1.5% |
| Second moment, major (Iy) | 2,770 cm⁴ | 2,576 cm⁴ | +7.5% |
| Plastic modulus, major (Wpl,y) | 285 cm³ | 278.58 cm³ | +2.3% |
| Elastic modulus, major (Wel,y) | 252 cm³ | 249.08 cm³ | +1.2% |
| Second moment, minor (Iz) | 205 cm⁴ | 331.7 cm⁴ | -38.2% |
| Plastic modulus, minor (Wpl,z) | 58.1 cm³ | 76.364 cm³ | -23.9% |
| Radius of gyration, minor (iz) | 2.48 cm | 3.12 cm | -20.5% |
| Torsion constant (It) | 9.03 cm⁴ | 7.16 cm⁴ | +26.1% |
IPE 220 to EN 10365 · Continental Steel; W 8X18 to AISC Shapes Database v16.0. Difference is expressed relative to W 8X18.
How to choose between them
On stiffness, IPE 220 has the larger second moment of area: 2,770 cm⁴ against 2,576 cm⁴, a difference of 7.5%. 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 220 is the more efficient section: 10.9 against 10.4 cm³ per kg/m, 4.6% 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.
The two diverge much more about the minor axis: W 8X18 has 76.364 cm³ of minor-axis plastic modulus against 58.1 cm³, 23.9% 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. IPE sections are specified to EN 10365 · Continental Steel and W 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 2.2% weight.
In short, IPE 220 is the stronger section and IPE 220 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.