W6×16 vs W6×20

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

W6×20 is the heavier section at 20 lb per foot, versus 16 for W6×16 (4 lb/ft more).

Both are nominally 6 in. deep.

W6×20 has the greater bending strength: section modulus Sx of 13.4 in³ versus 10.2, about 31% more.

PropertyW6×16W6×20
Weight16 lb/ft20 lb/ft
Depth (d)6 1/4"6 1/4"
Flange width (bf)4"6"
Web thickness (tw)1/4"1/4"
Flange thickness (tf)3/8"3/8"
Area (A)4.74 in²5.87 in²
Moment of inertia (Ix)32.1 in⁴41.4 in⁴
Section modulus (Sx)10.2 in³13.4 in³
Plastic modulus (Zx)11.7 in³14.9 in³

Open W6×16 in the interactive size chart →

Full detail: W6×16 · W6×20. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.

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