W18×234 vs W18×258
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W18×258 is the heavier section at 258 lb per foot, versus 234 for W18×234 (24 lb/ft more).
Both are nominally 18 in. deep.
W18×258 has the greater bending strength: section modulus Sx of 514 in³ versus 466, about 10% more.
| Property | W18×234 | W18×258 |
|---|---|---|
| Weight | 234 lb/ft | 258 lb/ft |
| Depth (d) | 21" | 21 1/2" |
| Flange width (bf) | 11 5/8" | 11 3/4" |
| Web thickness (tw) | 1 3/16" | 1 1/4" |
| Flange thickness (tf) | 2 1/8" | 2 5/16" |
| Area (A) | 68.6 in² | 76 in² |
| Moment of inertia (Ix) | 4900 in⁴ | 5510 in⁴ |
| Section modulus (Sx) | 466 in³ | 514 in³ |
| Plastic modulus (Zx) | 549 in³ | 611 in³ |
Open W18×234 in the interactive size chart →
Full detail: W18×234 · W18×258. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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