Steel Beam Sizes / AISC / HSS Square / HSS 18x18x3/8

HSS 18x18x3/8 Dimensions, Weight and Section Properties

AISC Square HSS · v16.0

HSS 18x18x3/8: 88.73 lb/ft weight. View the full dimensions and properties in imperial and metric units below.

Analyze in Beam Calculator Back to HSS Square

Need this steel supplied or fabricated?

Request project pricing for delivery in the United States or Canada.

Get a steel quote →

Diagram, properties emphasis, and nearby alternatives use the selected unit system.

Units

Section diagram

HSS 18x18x3/8 dimensions

Not to scale. Dimensions shown for reference.

Section properties

Symbols match the steel section finder. Imperial and metric values are shown side by side.

Property Imperial Metric
Weight 88.73 lb/ft 132.00 kg/m
Height 18.00 in 457.00 mm
Width 18.00 in 457.00 mm
Nominal tw 0.375 in 9.530 mm
Design tw 0.349 in 8.860 mm
Area 24.30 in² 15,700.00 mm²
Ix 1,250.00 in⁴ 520,000,000 mm⁴
Iy 1,250.00 in⁴ 520,000,000 mm⁴
Sx 139.00 in³ 2,280,000 mm³
Sy 139.00 in³ 2,280,000 mm³
Zx 160.00 in³ 2,620,000 mm³
Zy 160.00 in³ 2,620,000 mm³
rx 7.18 in 182.00 mm
ry 7.18 in 182.00 mm
J 1,940.00 in⁴ 807,000,000 mm⁴

Alternatives

Useful nearby sections

Compare weight neighbors, another Ix option, and a nearby depth series when available, with percent change versus HSS 18x18x3/8.

Lighter in Square HSS

HSS 20x20x5/16

Weight
82.9 lb/ft (-6.6%)
Depth
20.00 in (+11%)
Ix
1,460.0 in⁴ (+17%)

Heavier in Square HSS

HSS 10x10x3/4

Weight
89.5 lb/ft (+0.9%)
Depth
10.00 in (-44%)
Ix
347.0 in⁴ (-72%)

Another Iₓ option in Square HSS

HSS 14x14x1

Weight
168.2 lb/ft (+90%)
Depth
14.00 in (-22%)
Ix
1,290.0 in⁴ (+3.2%)
Analyze in Beam Calculator Compare in HSS Square finder

Source: AISC Shapes Database v16.0 · Methodology