W6×15 vs W8×15
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W6×15 and W8×15 both weigh 15 lb per foot, so the choice comes down to depth and stiffness rather than weight.
W8×15 is the deeper section at a nominal 8 in., versus 6 in.
W8×15 has the greater bending strength: section modulus Sx of 11.8 in³ versus 9.72, about 21% more.
| Property | W6×15 | W8×15 |
|---|---|---|
| Weight | 15 lb/ft | 15 lb/ft |
| Depth (d) | 6" | 8 1/8" |
| Flange width (bf) | 6" | 4" |
| Web thickness (tw) | 1/4" | 1/4" |
| Flange thickness (tf) | 1/4" | 5/16" |
| Area (A) | 4.43 in² | 4.44 in² |
| Moment of inertia (Ix) | 29.1 in⁴ | 48 in⁴ |
| Section modulus (Sx) | 9.72 in³ | 11.8 in³ |
| Plastic modulus (Zx) | 10.8 in³ | 13.6 in³ |
Open W6×15 in the interactive size chart →
Full detail: W6×15 · W8×15. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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