W6×8.5 vs W6×9
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W6×9 is the heavier section at 9 lb per foot, versus 8.5 for W6×8.5 (0.5 lb/ft more).
Both are nominally 6 in. deep.
W6×9 has the greater bending strength: section modulus Sx of 5.56 in³ versus 5.1, about 9% more.
| Property | W6×8.5 | W6×9 |
|---|---|---|
| Weight | 8.5 lb/ft | 9 lb/ft |
| Depth (d) | 5 7/8" | 5 7/8" |
| Flange width (bf) | 4" | 4" |
| Web thickness (tw) | 3/16" | 3/16" |
| Flange thickness (tf) | 3/16" | 3/16" |
| Area (A) | 2.52 in² | 2.68 in² |
| Moment of inertia (Ix) | 14.9 in⁴ | 16.4 in⁴ |
| Section modulus (Sx) | 5.1 in³ | 5.56 in³ |
| Plastic modulus (Zx) | 5.73 in³ | 6.23 in³ |
Open W6×8.5 in the interactive size chart →
Full detail: W6×8.5 · W6×9. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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