How is HSS weight per foot calculated?

HSS weight per foot is calculated from the cross-sectional area: W (lb/ft) = A (in²) × 3.40, where 3.40 is the weight of 1 in² of steel per foot (490 lb/ft³ × 144 in²/ft² ÷ 144 in²/ft² = 3.40 lb/ft per in²). For square/rectangular HSS, area = 2t(w + h − 2t) − (4 − π) × t × (ri + ro)/2 approximately, where t = wall thickness, w = width, h = height, ri/ro = inside/outside corner radii. For round HSS, area = π(OD − t) × t. The design wall thickness = 0.93 × nominal wall thickness per AISC 360 Table B4.1 for electric-resistance-welded HSS to account for manufacturing tolerance. Example: HSS6×6×3/8 = 6.89 in² → W = 6.89 × 3.40 = 23.43 lb/ft (tabulated 23.48 lb/ft, small difference from corner radii). The AISC Steel Construction Manual Table 1-12 provides tabulated weights. Weight per foot is critical for: (1) estimating steel tonnage, (2) erection lift planning (crane capacity), and (3) shipping cost estimation.

What is the difference between A500 Gr B, Gr C, and A1085 HSS?

The three principal HSS specifications differ in strength, tolerances, and toughness: A500 Gr B — Fy = 46 ksi (rectangular) / 42 ksi (round), Fu = 58 ksi. The most common structural HSS specification, used for 90%+ of structural applications. Wall thickness tolerance: ±10%. A500 Gr C — Fy = 50 ksi (rectangular) / 46 ksi (round), Fu = 62 ksi. Higher strength than Gr B by 8-19%, increasingly specified for columns and bracing where strength governs over serviceability. A1085 — Fy = 50 ksi (all shapes), Fu = 65 ksi. Newer specification (introduced 2010s) with: (1) tighter wall tolerance: ±10% (vs A500's −10%/+unlimited), eliminating the 0.93 design thickness reduction, (2) mandatory Charpy V-notch testing at 40°F (4°C) for fracture-critical/seismic applications, (3) maximum Fy/Fu ratio of 0.85 ensuring adequate strain-hardening for plastic design. A1085 provides approximately 12% more compression capacity than A500 Gr B for the same nominal size because the design thickness is not reduced by 0.93. A501 hot-formed HSS (Fy = 36 ksi) is largely superseded by cold-formed A500/A1085. For structural columns, use A500 Gr C or A1085; for general applications, A500 Gr B is standard; for seismic/fracture-critical, specify A1085 with CVN testing.

How do square, rectangular, and round HSS compare for column design?

Square, rectangular, and round HSS each have distinct advantages for column applications: Square HSS (e.g., HSS6×6) — equal rx and ry (radius of gyration same both axes), so no weak-axis buckling penalty. Most efficient for axially-loaded columns where biaxial bending is not significant. Clean, flat sides for architectural appearance and simple beam connections. Rectangular HSS (e.g., HSS8×4) — rx ≠ ry, so the weak axis controls unless braced. Efficient when strong-axis bending governs and weak-axis is braced (e.g., wall columns with weak-axis lateral support from girts). Used as truss chords where depth is needed in one direction only. Round HSS (e.g., HSS6.625×0.280) — rx = ry in all directions (polar symmetry), so no weak-axis buckling penalty regardless of loading direction. Superior for: biaxially-loaded columns (wind from any direction), architecturally exposed columns (no preferred orientation), sign structures and flagpoles, and concrete-filled columns where round shape provides optimal confinement. The torsional constant J is much higher for round HSS, making it superior for torsional loading. For a given weight per foot: round HSS typically has larger diameter and thinner wall than the equivalent square HSS, giving higher rx but potentially lower local buckling resistance (controlled by D/t ratio vs b/t ratio).

What are the typical HSS applications by size and shape?

HSS applications follow typical size ranges based on structural function: Columns (low-rise 1−3 stories): HSS6×6 to HSS10×10 square, carrying 50−300 kips. The clean appearance eliminates the need for architectural cladding. Columns (mid-rise): HSS10×10 to HSS14×14, sometimes concrete-filled for higher capacity (composite columns per AISC 360 Chapter I). Bracing (X, V, chevron): HSS4×4 to HSS8×8 square or rectangular. Square preferred for balanced tension/compression capacity. HSS braces are more efficient than W-shape braces because rx ≈ ry eliminates weak-axis buckling. Truss chords: HSS6×6 to HSS12×12 square, or rectangular for single-plane trusses. The closed section provides high torsional stiffness, important for truss chord stability during erection. Truss webs: HSS4×4 to HSS6×6 square. HSS webs are preferred over angles because the closed section eliminates torsional-flexural buckling modes. Canopy/awning columns: HSS6×6 to HSS8×8 square or HSS6 to HSS10 round, architecturally exposed and painted. Bollards: HSS6 to HSS10 round, concrete-filled for vehicle impact resistance. Handrails: HSS1.66 to HSS2 round (1.66″ OD = 1-1/4″ NPS pipe size). ADA requires gripping surface between 1-1/4″ and 2″ diameter. Sign structures: HSS8×8 to HSS14×14 square or round, governed by wind and fatigue loading.

How does HSS wall thickness affect local buckling and column capacity?

HSS wall slenderness (width-to-thickness ratio b/t or diameter-to-thickness D/t) directly controls local buckling, which reduces column compression capacity. Per AISC 360 Table B4.1a: For rectangular HSS flanges: compact limit λp = 1.12√(E/Fy), noncompact limit λr = 1.40√(E/Fy). For A500 Gr B (Fy = 46 ksi): λp = 28.1, λr = 35.2. For A500 Gr C (Fy = 50 ksi): λp = 27.0, λr = 33.7. For round HSS: compact limit λp = 0.07E/Fy, noncompact limit λr = 0.31E/Fy. For Fy = 46 ksi: λp = 44.1 (D/t), λr = 195. Example — HSS6×6×3/16: b/t = (6 − 2×0.1875)/0.1875 = 30.0. For Gr B (λp = 28.1): 30.0 > 28.1, section is noncompact → Qs < 1.0 reduces compression capacity. HSS6×6×1/4: b/t = (6 − 2×0.25)/0.25 = 22.0 < 28.1, compact → full capacity. The thicker wall (1/4″ vs 3/16″) doubles the weight (16.32 vs 8.15 lb/ft) but provides full compact-section capacity. For column design: always check the slenderness classification. Noncompact or slender HSS sections are penalized by the Qs (stiffened element) reduction factor per AISC E7. A1085 HSS with its tighter wall tolerance eliminates the 0.93 design thickness reduction, giving approximately 12% more compression area and improving the b/t ratio by about 7% for the same nominal section.

Steel HSS Weight — Hollow Section Weight per Foot

Hollow Structural Sections (HSS) are used for columns, braces, truss members, and architecturally exposed steel. Available in square, rectangular, and round shapes. This page provides weight per foot data for common HSS sections.

Square HSS

Designation	Weight (lb/ft)	Area (in²)	Ix (in⁴)	Sx (in³)	rx (in)
HSS2x2x1/8	2.67	0.784	0.40	0.40	0.71
HSS2x2x3/16	3.68	1.08	0.51	0.51	0.69
HSS2-1/2x2-1/2x1/8	3.43	1.01	0.82	0.66	0.90
HSS2-1/2x2-1/2x3/16	4.80	1.41	1.07	0.86	0.87
HSS3x3x1/8	4.19	1.23	1.51	1.01	1.11
HSS3x3x3/16	5.93	1.74	2.02	1.35	1.08
HSS3x3x1/4	7.50	2.20	2.43	1.62	1.05
HSS3-1/2x3-1/2x3/16	7.05	2.07	3.43	1.96	1.29
HSS3-1/2x3-1/2x1/4	8.98	2.64	4.19	2.39	1.26
HSS4x4x1/8	5.71	1.68	3.85	1.92	1.51
HSS4x4x3/16	8.15	2.39	5.27	2.63	1.48
HSS4x4x1/4	10.46	3.07	6.53	3.27	1.46
HSS4x4x5/16	12.64	3.71	7.63	3.82	1.43
HSS5x5x3/16	10.38	3.05	10.77	4.31	1.88
HSS5x5x1/4	13.39	3.93	13.53	5.41	1.86
HSS5x5x3/8	19.08	5.60	17.88	7.15	1.79
HSS6x6x3/16	12.61	3.70	19.12	6.37	2.27
HSS6x6x1/4	16.32	4.79	24.16	8.05	2.25
HSS6x6x3/8	23.48	6.89	32.52	10.84	2.17
HSS6x6x1/2	29.85	8.76	38.20	12.73	2.09
HSS7x7x1/4	19.25	5.65	39.49	11.28	2.64
HSS7x7x3/8	27.88	8.18	53.54	15.30	2.56
HSS7x7x1/2	35.80	10.50	63.67	18.19	2.46
HSS8x8x1/4	22.18	6.51	60.05	15.01	3.04
HSS8x8x3/8	32.28	9.47	82.16	20.54	2.95
HSS8x8x1/2	41.62	12.21	100.10	25.03	2.86
HSS8x8x5/8	50.22	14.74	114.05	28.51	2.78
HSS10x10x3/8	41.10	12.06	168.67	33.73	3.74
HSS10x10x1/2	53.20	15.62	209.90	41.98	3.67
HSS10x10x5/8	64.62	18.96	244.90	48.98	3.60
HSS12x12x3/8	49.92	14.65	305.04	50.84	4.56
HSS12x12x1/2	64.77	19.01	384.00	64.00	4.50

Rectangular HSS

Designation	Weight (lb/ft)	Area (in²)	Ix (in⁴)	rx (in)
HSS3x2x3/16	4.80	1.41	1.48	1.02
HSS3x2x1/4	6.10	1.79	1.77	0.99
HSS4x2x1/4	7.50	2.20	4.21	1.38
HSS4x3x3/16	7.05	2.07	3.91	1.37
HSS4x3x1/4	8.98	2.64	4.85	1.35
HSS5x3x3/16	8.15	2.39	7.37	1.76
HSS5x3x1/4	10.46	3.07	9.19	1.73
HSS5x3-1/2x3/16	8.80	2.58	8.63	1.83
HSS6x3x3/16	8.67	2.55	11.45	2.12
HSS6x3x1/4	11.22	3.29	14.45	2.10
HSS6x4x3/16	9.99	2.93	14.26	2.21
HSS6x4x1/4	12.95	3.80	18.07	2.18
HSS6x4x3/8	18.49	5.42	24.12	2.11
HSS8x4x3/16	11.58	3.40	27.75	2.86
HSS8x4x1/4	15.05	4.42	35.43	2.83
HSS8x4x3/8	21.74	6.38	47.98	2.74
HSS8x4x1/2	27.85	8.17	57.33	2.65
HSS8x6x3/16	13.01	3.82	36.77	3.10
HSS8x6x1/4	16.96	4.98	47.21	3.08
HSS8x6x3/8	24.64	7.23	64.56	2.99
HSS8x6x1/2	31.73	9.31	78.24	2.90
HSS10x4x3/16	12.74	3.74	49.68	3.64
HSS10x4x3/8	23.96	7.03	86.95	3.52
HSS10x6x3/8	27.40	8.04	117.15	3.82
HSS10x6x1/2	35.38	10.39	143.26	3.71
HSS12x4x3/8	26.40	7.75	133.39	4.15
HSS12x6x3/8	30.16	8.85	173.61	4.43
HSS12x6x1/2	39.03	11.45	214.01	4.32
HSS12x8x3/8	33.92	9.96	226.58	4.77
HSS12x8x1/2	44.02	12.92	282.66	4.68

Round HSS

Designation	Weight (lb/ft)	Area (in²)	I (in⁴)	S (in³)	r (in)
HSS1.66x0.14	2.30	0.675	0.19	0.23	0.53
HSS2x0.14	2.82	0.828	0.34	0.34	0.64
HSS2.5x0.14	3.57	1.05	0.64	0.51	0.78
HSS2.5x0.19	4.72	1.39	0.81	0.65	0.76
HSS3x0.19	5.73	1.68	1.46	0.97	0.93
HSS3x0.25	7.37	2.16	1.80	1.20	0.91
HSS3.5x0.19	6.74	1.98	2.38	1.36	1.10
HSS3.5x0.25	8.68	2.55	2.96	1.69	1.08
HSS3.5x0.32	10.88	3.19	3.56	2.03	1.06
HSS4x0.22	8.82	2.59	4.10	2.05	1.26
HSS4x0.32	12.55	3.68	5.55	2.78	1.23
HSS5x0.25	12.70	3.72	9.04	3.62	1.56
HSS5x0.32	15.97	4.69	11.07	4.43	1.54
HSS5x0.50	23.81	6.99	15.20	6.08	1.47
HSS6x0.25	15.38	4.51	16.12	5.37	1.89
HSS6x0.32	19.38	5.69	19.85	6.62	1.87
HSS6x0.50	29.10	8.54	27.91	9.30	1.81
HSS8x0.32	26.18	7.68	51.90	12.98	2.60
HSS8x0.50	39.82	11.69	74.79	18.70	2.53
HSS10x0.32	33.02	9.69	104.16	20.83	3.28
HSS10x0.50	50.55	14.82	152.58	30.52	3.21
HSS12x0.38	47.14	13.84	224.83	37.47	4.03
HSS12x0.50	61.25	17.97	286.83	47.81	3.99
HSS14x0.38	55.25	16.21	368.08	52.58	4.77
HSS14x0.50	71.84	21.07	472.40	67.49	4.74
HSS16x0.38	63.37	18.59	569.75	71.22	5.54
HSS16x0.50	82.45	24.18	735.18	91.90	5.51

ASTM Specifications

Spec	Grade	Fy (ksi)	Use
A500 Gr B	—	46 (rect) / 42 (round)	Most common HSS
A500 Gr C	—	50 (rect) / 46 (round)	Higher strength
A501	—	36	Hot-formed
A1085	—	50	Tight tolerances, Charpy tested

Typical HSS Applications

Application	Typical Size	Notes
Columns (low-rise)	HSS6x6 to HSS10x10	Architectural, clean appearance
Bracing	HSS4x4 to HSS8x8	X, V, chevron bracing
Truss chords	HSS6x6 to HSS12x12	Square or round
Truss webs	HSS4x4 to HSS6x6	Square or round
Canopy columns	HSS6x6 to HSS8x8	Exposed, painted
Sign structures	HSS8x8 to HSS14x14	Round or square
Bollards	HSS6 to HSS10 (round)	Filled with concrete
Handrails	HSS1.66 to HSS2 (round)	Top and mid rails

Frequently Asked Questions

How much does HSS6x6x3/8 weigh? 23.48 lb/ft. A 20-foot piece weighs approximately 470 lb.

What is the difference between A500 Gr B and Gr C? Gr B has Fy = 46 ksi (rectangular) or 42 ksi (round). Gr C has Fy = 50 ksi (rectangular) or 46 ksi (round). Gr C is 8-19% stronger and is increasingly specified for structural applications.

What is A1085 HSS? A1085 is a newer specification with tighter wall thickness tolerances (±10% vs A500's -10%), a minimum Fy of 50 ksi, and mandatory Charpy V-notch testing. It is preferred for fracture-critical and seismic applications.

Can round HSS be used for columns? Yes. Round HSS is commonly used for columns, especially in architecturally exposed applications. The radius of gyration is the same in all directions, making round HSS efficient for biaxial bending.

Steel Weight Calculator — Weight by dimensions
Steel Angle Weight — L shape weights
Steel Channel Weight — C and MC shapes
Section Properties — Full section database
Steel Weight per Foot — All shapes chart

Disclaimer

This is a calculation tool, not a substitute for professional engineering certification. All results must be independently verified by a licensed Professional Engineer (PE) or Structural Engineer (SE) before use in construction, fabrication, or permit documents. The user is responsible for the accuracy of all inputs and the verification of all outputs.