C9×20 channel

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.

C9×20 measures 9 in. deep with a 2 5/8 in. flange and a 7/16 in. web.

At 20 lb per foot it is the heaviest of the 3 C9 sizes, which run from 13.4 to 20 lb/ft.

For strong-axis bending its section modulus is Sx = 13.5 in³ and its moment of inertia Ix = 60.9 in⁴, with a plastic modulus Zx = 16.9 in³.

Detailing dimensions

Depth (d)9"
Flange width (bf)2 5/8"
Web thickness (tw)7/16"
Avg flange thickness (tf)7/16"
k (detailing)1"

Section properties

Weight20 lb/ft
Area (A)5.87 in²
Ix60.9 in⁴
Sx13.5 in³
Zx16.9 in³
rx3.22 in
Iy2.41 in⁴
Sy1.17 in³
Zy2.46 in³
ry0.64 in
J0.427 in⁴

Other C9 sizes

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

C9×13.4C9×15

Similar weight channels

Comparable 20 lb/ft sections in other channel sizes.

C10×2020 lb/ft · Sx 15.8 in³C12×20.720.7 lb/ft · Sx 21.5 in³C8×18.7518.75 lb/ft · Sx 11 in³C10×15.315.3 lb/ft · Sx 13.5 in³C12×2525 lb/ft · Sx 24 in³C10×2525 lb/ft · Sx 18.2 in³C7×14.7514.75 lb/ft · Sx 7.78 in³C8×13.7513.75 lb/ft · Sx 9.02 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 C9×20 cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: Channels · Steel Beam Size Chart

Interactive drawing