W30×90 vs W30×99
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W30×99 is the heavier section at 99 lb per foot, versus 90 for W30×90 (9 lb/ft more).
Both are nominally 30 in. deep.
W30×99 has the greater bending strength: section modulus Sx of 269 in³ versus 245, about 10% more.
| Property | W30×90 | W30×99 |
|---|---|---|
| Weight | 90 lb/ft | 99 lb/ft |
| Depth (d) | 29 1/2" | 29 5/8" |
| Flange width (bf) | 10 3/8" | 10 1/2" |
| Web thickness (tw) | 1/2" | 1/2" |
| Flange thickness (tf) | 5/8" | 11/16" |
| Area (A) | 26.3 in² | 29 in² |
| Moment of inertia (Ix) | 3610 in⁴ | 3990 in⁴ |
| Section modulus (Sx) | 245 in³ | 269 in³ |
| Plastic modulus (Zx) | 283 in³ | 312 in³ |
Open W30×90 in the interactive size chart →
Full detail: W30×90 · W30×99. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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