HSS12x12x3/8 — Dimensions, Weight & Section Properties
Hollow structural section per ASTM A500 / AISC Steel Construction Manual
HSS12x12x3/8 is an American hollow structural section (HSS) 12×12 inches (304.8×304.8 mm) with a nominal 0.375 in wall, weighing 58.1 pounds per foot (86.5 kg/m). Section properties below are the AISC published values, computed with the A500 design wall thickness of 0.93×nominal — with metric equivalents alongside.
Typical uses: columns, braces, truss members, equipment frames, and architectural steel — closed sections excel in compression and torsion and take paint beautifully. For a quick stiffness check, see the deflection example below or open the beam calculator with your own span and load.
Dimensions
| Height h | 12 in (304.8 mm) |
| Width b | 12 in (304.8 mm) |
| Nominal wall t | 0.375 in (9.5 mm) |
| Design wall (0.93t) | 0.349 in (8.9 mm) |
Weight & Cross-Section
| Weight per foot | 58.1 lb/ft (86.5 kg/m) |
| 20 ft bar | 1,162 lb |
| 40 ft bar | 2,324 lb |
| Area A | 16 in² (103.2 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 357 in⁴ (14,859 cm⁴) |
| Section modulus Sx | 59.5 in³ (975 cm³) |
| Radius of gyration rx | 4.73 in |
| Moment of inertia Iy | 357 in⁴ (14,859 cm⁴) |
| Section modulus Sy | 59.5 in³ (975 cm³) |
| Radius of gyration ry | 4.73 in |
Compared with the neighbouring sizes
| Shape | h × b (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| HSS12x12x3/8 (this page) | 12 × 12 | 58.1 | 357 | 59.5 | — | — |
| HSS12x12x1/2 | 12 × 12 | 76.07 | 457 | 76.2 | +31 % | +28 % |
Deflection example
A simply supported HSS12x12x3/8 spanning 19 ft with a 10 kip point load at midspan deflects 0.24 in (E = 29,000 ksi, Ix = 357 in⁴). The L/360 serviceability limit for this span is 0.63 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a HSS12x12x3/8 tube weigh?
HSS12x12x3/8 weighs 58.1 pounds per foot (86.5 kg/m). A 20 ft bar weighs 1,162 lb and a 40 ft bar 2,324 lb.
What are the dimensions of a HSS12x12x3/8?
HSS12x12x3/8 is 12×12 in (304.8×304.8 mm) outside, with a nominal wall of 0.375 in. Note that A500 tolerances put the design wall at 0.93×nominal (0.349 in) — the section properties listed already account for this.
What are the dimensions of a HSS12x12x3/8 in mm?
HSS12x12x3/8 is 304.8×304.8 mm outside with a nominal wall of 9.5 mm. In metric section properties: Ix = 14,859 cm⁴, Sx = 975 cm³.
How much does a HSS12x12x3/8 weigh in kg?
86.5 kg per meter. A 6 m bar weighs 519 kg and a 12 m bar 1,038 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a HSS12x12x3/8?
About the strong axis, Ix = 357 in⁴ (14,859 cm⁴) with section modulus Sx = 59.5 in³. About the weak axis, Iy = 357 in⁴ and Sy = 59.5 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
HSS12x12x3/8 or HSS12x12x1/2 — what does one size up change?
HSS12x12x1/2 is about 31% heavier (76.07 vs 58.1 lb/ft) but about 28% stiffer (Ix 457 vs 357 in⁴). Going one step up within the same depth group is usually the cheapest way to cut deflection.
Values are entered from the governing standard’s published tables and cross-checked programmatically against its mass and section formulas before publication. Spotted an error? Write to advertising@metalabout.net — verified corrections ship within days. About