W16×40 vs W16×45
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W16×45 is the heavier section at 45 lb per foot, versus 40 for W16×40 (5 lb/ft more).
Both are nominally 16 in. deep.
W16×45 has the greater bending strength: section modulus Sx of 72.7 in³ versus 64.7, about 12% more.
| Property | W16×40 | W16×45 |
|---|---|---|
| Weight | 40 lb/ft | 45 lb/ft |
| Depth (d) | 16" | 16 1/8" |
| Flange width (bf) | 7" | 7" |
| Web thickness (tw) | 5/16" | 3/8" |
| Flange thickness (tf) | 1/2" | 9/16" |
| Area (A) | 11.8 in² | 13.3 in² |
| Moment of inertia (Ix) | 518 in⁴ | 586 in⁴ |
| Section modulus (Sx) | 64.7 in³ | 72.7 in³ |
| Plastic modulus (Zx) | 73 in³ | 82.3 in³ |
Open W16×40 in the interactive size chart →
Full detail: W16×40 · W16×45. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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