W14×48 vs W21×48
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W14×48 and W21×48 both weigh 48 lb per foot, so the choice comes down to depth and stiffness rather than weight.
W21×48 is the deeper section at a nominal 21 in., versus 14 in.
W21×48 has the greater bending strength: section modulus Sx of 93 in³ versus 70.2, about 32% more.
| Property | W14×48 | W21×48 |
|---|---|---|
| Weight | 48 lb/ft | 48 lb/ft |
| Depth (d) | 13 3/4" | 20 5/8" |
| Flange width (bf) | 8" | 8 1/8" |
| Web thickness (tw) | 5/16" | 3/8" |
| Flange thickness (tf) | 5/8" | 7/16" |
| Area (A) | 14.1 in² | 14.1 in² |
| Moment of inertia (Ix) | 484 in⁴ | 959 in⁴ |
| Section modulus (Sx) | 70.2 in³ | 93 in³ |
| Plastic modulus (Zx) | 78.4 in³ | 107 in³ |
Open W14×48 in the interactive size chart →
Full detail: W14×48 · W21×48. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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