HSS18×18×1 square/rectangular HSS tube

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.

HSS18×18×1 is a square tube 18 in. by 18 in. with a 1 in. nominal wall.

At 222.63 lb per foot it is the heaviest of the 8 HSS18×18 sizes, which run from 59.85 to 222.63 lb/ft.

For strong-axis bending its section modulus is Sx = 324 in³ and its moment of inertia Ix = 2920 in⁴, with a plastic modulus Zx = 387 in³.

Detailing dimensions

Depth (Ht)18"
Width (B)18"
Nominal wall (t)1"

Section properties

Weight222.63 lb/ft
Area (A)61.3 in²
Ix2920 in⁴
Sx324 in³
Zx387 in³
rx6.9 in
Iy2920 in⁴
Sy324 in³
Zy387 in³
ry6.9 in
J4740 in⁴

Other HSS18×18 sizes

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

HSS18×18×1/4HSS18×18×5/16HSS18×18×3/8HSS18×18×1/2HSS18×18×5/8HSS18×18×3/4HSS18×18×7/8

All HSS18×18 sizes and dimensions →

Similar weight HSS shapes

Comparable 222.63 lb/ft sections in other HSS tube sizes.

HSS24×12×1222.63 lb/ft · Sx 362 in³HSS30×10×7/8221.06 lb/ft · Sx 413 in³HSS20×20×7/8221.06 lb/ft · Sx 367 in³HSS28.000×0.750218.48 lb/ft · Sx 398 in³HSS24.000×0.875216.31 lb/ft · Sx 332 in³HSS34×10×3/4212 lb/ft · Sx 444 in³HSS24×20×3/4212 lb/ft · Sx 413 in³HSS22×22×3/4212 lb/ft · Sx 395 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 HSS18×18×1 cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: HSS tube · Steel Beam Size Chart

Interactive drawing