S20×86 standard 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.

S20×86 measures 20 1/4 in. deep with a 7 in. flange, on a 11/16 in. web and 15/16 in. flanges.

At 86 lb per foot it is one of the 4 S20 sizes, which run from 66 to 96 lb/ft.

For strong-axis bending its section modulus is Sx = 155 in³ and its moment of inertia Ix = 1570 in⁴, with a plastic modulus Zx = 183 in³.

Detailing dimensions

Depth (d)20 1/4"
Flange width (bf)7"
Web thickness (tw)11/16"
Flange thickness (tf)15/16"
k (detailing)1 3/4"
Workable gage (g)4"

Section properties

Weight86 lb/ft
Area (A)25.3 in²
Ix1570 in⁴
Sx155 in³
Zx183 in³
rx7.89 in
Iy46.6 in⁴
Sy13.2 in³
Zy23.1 in³
ry1.36 in
J6.65 in⁴

Other S20 sizes

Same nominal size, different weight — useful when you are checking a substitution or a lighter section.

S20×66S20×75S20×96

Similar weight standard beams

Comparable 86 lb/ft sections in other standard beam sizes.

S24×9090 lb/ft · Sx 187 in³S24×8080 lb/ft · Sx 175 in³S24×100100 lb/ft · Sx 199 in³S18×7070 lb/ft · Sx 103 in³S24×106106 lb/ft · Sx 240 in³S18×54.754.7 lb/ft · Sx 89 in³S24×121121 lb/ft · Sx 258 in³S15×5050 lb/ft · Sx 64.7 in³

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 S20×86 cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: Standard beams · Steel Beam Size Chart

Interactive drawing