W21×166 wide-flange beam
Detailing dimensions and section properties from the AISC Shapes Database, 16th Edition. Values are shown to the nearest 1/16 in. as they appear on a shop drawing.
W21×166 measures 22 1/2 in. deep with a 12 3/8 in. flange, on a 3/4 in. web and 1 3/8 in. flanges.
At 166 lb per foot it is one of the 21 W21 sizes, which run from 44 to 275 lb/ft.
For strong-axis bending its section modulus is Sx = 380 in³ and its moment of inertia Ix = 4280 in⁴, with a plastic modulus Zx = 432 in³.
Detailing dimensions
| Depth (d) | 22 1/2" |
|---|---|
| Flange width (bf) | 12 3/8" |
| Web thickness (tw) | 3/4" |
| Flange thickness (tf) | 1 3/8" |
| k (detailing) | 2 5/8" |
| Workable gage (g) | 5 1/2" |
Section properties
| Weight | 166 lb/ft |
|---|---|
| Area (A) | 48.8 in² |
| Ix | 4280 in⁴ |
| Sx | 380 in³ |
| Zx | 432 in³ |
| rx | 9.36 in |
| Iy | 435 in⁴ |
| Sy | 70 in³ |
| Zy | 108 in³ |
| ry | 2.99 in |
| J | 23.6 in⁴ |
Other W21 sizes
Same nominal size, different weight — useful when you are checking a substitution or a lighter section.
All W21 sizes and dimensions →
Similar weight wide-flange beams
Comparable 166 lb/ft sections in other wide-flange beam sizes.
Compare W21×166 with a nearby size
Detailing values are rounded to the nearest 1/16 in. per the AISC Steel Construction Manual. Verify critical dimensions against the current Manual before fabrication. Need W21×166 cut, formed, or fabricated? Huntington Steel & Supply Co.
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