W8×13 vs W8×15

A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.

W8×15 is the heavier section at 15 lb per foot, versus 13 for W8×13 (2 lb/ft more).

Both are nominally 8 in. deep.

W8×15 has the greater bending strength: section modulus Sx of 11.8 in³ versus 9.91, about 19% more.

PropertyW8×13W8×15
Weight13 lb/ft15 lb/ft
Depth (d)8"8 1/8"
Flange width (bf)4"4"
Web thickness (tw)1/4"1/4"
Flange thickness (tf)1/4"5/16"
Area (A)3.84 in²4.44 in²
Moment of inertia (Ix)39.6 in⁴48 in⁴
Section modulus (Sx)9.91 in³11.8 in³
Plastic modulus (Zx)11.4 in³13.6 in³

Open W8×13 in the interactive size chart →

Full detail: W8×13 · W8×15. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.

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