W16×31 vs W16×36
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W16×36 is the heavier section at 36 lb per foot, versus 31 for W16×31 (5 lb/ft more).
Both are nominally 16 in. deep.
W16×36 has the greater bending strength: section modulus Sx of 56.5 in³ versus 47.2, about 20% more.
| Property | W16×31 | W16×36 |
|---|---|---|
| Weight | 31 lb/ft | 36 lb/ft |
| Depth (d) | 15 7/8" | 15 7/8" |
| Flange width (bf) | 5 1/2" | 7" |
| Web thickness (tw) | 1/4" | 5/16" |
| Flange thickness (tf) | 7/16" | 7/16" |
| Area (A) | 9.13 in² | 10.6 in² |
| Moment of inertia (Ix) | 375 in⁴ | 448 in⁴ |
| Section modulus (Sx) | 47.2 in³ | 56.5 in³ |
| Plastic modulus (Zx) | 54 in³ | 64 in³ |
Open W16×31 in the interactive size chart →
Full detail: W16×31 · W16×36. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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