W12×40 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.

W12×40 measures 12 in. deep with a 8 in. flange, on a 5/16 in. web and 1/2 in. flanges.

At 40 lb per foot it is one of the 29 W12 sizes, which run from 14 to 336 lb/ft.

For strong-axis bending its section modulus is Sx = 51.5 in³ and its moment of inertia Ix = 307 in⁴, with a plastic modulus Zx = 57 in³.

Detailing dimensions

Depth (d)12"
Flange width (bf)8"
Web thickness (tw)5/16"
Flange thickness (tf)1/2"
k (detailing)1 3/8"
Workable gage (g)5 1/2"

Section properties

Weight40 lb/ft
Area (A)11.7 in²
Ix307 in⁴
Sx51.5 in³
Zx57 in³
rx5.13 in
Iy44.1 in⁴
Sy11 in³
Zy16.8 in³
ry1.94 in
J0.906 in⁴

Other W12 sizes

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

W12×14W12×16W12×19W12×22W12×26W12×30W12×35W12×45W12×50W12×53W12×58W12×65W12×72W12×79W12×87W12×96W12×106W12×120W12×136W12×152W12×170W12×190W12×210W12×230

All W12 sizes and dimensions →

Similar weight wide-flange beams

Comparable 40 lb/ft sections in other wide-flange beam sizes.

W18×4040 lb/ft · Sx 68.4 in³W16×4040 lb/ft · Sx 64.7 in³W8×4040 lb/ft · Sx 35.5 in³W10×3939 lb/ft · Sx 42.1 in³W14×3838 lb/ft · Sx 54.6 in³W14×4343 lb/ft · Sx 62.6 in³W16×3636 lb/ft · Sx 56.5 in³W21×4444 lb/ft · Sx 81.6 in³

Compare W12×40 with a nearby size

W12×35 vs W12×40W12×40 vs W12×45W8×40 vs W12×40W12×40 vs W16×40

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 W12×40 cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: Wide flange beams · Steel Beam Size Chart

Interactive drawing