W6x15 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W6x15 is an American wide-flange beam 5.99 inches (152.1 mm) deep with a 5.99 in (152.1 mm) flange, weighing 15 pounds per foot (22.3 kg/m) — that is what the "15" in the designation means. All values below are the standard AISC published section properties used in US structural design, with metric equivalents alongside.
Typical uses: floor and roof framing, columns, headers, and general steel construction. For a quick stiffness check, see the deflection example below or open the beam calculator with your own span and load.
W6x15: cross-section drawn to scale from the AISC dimensions (d 5.99, bf 5.99, tw 0.23, tf 0.26 in)Dimensions
| Depth d | 5.99 in (152.1 mm) |
| Flange width bf | 5.99 in (152.1 mm) |
| Web thickness tw | 0.23 in (5.8 mm) |
| Flange thickness tf | 0.26 in (6.6 mm) |
Weight & Cross-Section
| Weight per foot | 15 lb/ft (22.3 kg/m) |
| 20 ft bar | 300 lb |
| 40 ft bar | 600 lb |
| Area A | 4.43 in² (28.6 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 29.1 in⁴ (1,211 cm⁴) |
| Section modulus Sx | 9.72 in³ (159 cm³) |
| Radius of gyration rx | 2.56 in |
| Moment of inertia Iy | 9.32 in⁴ (388 cm⁴) |
| Section modulus Sy | 3.11 in³ (51 cm³) |
| Radius of gyration ry | 1.45 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|
| W6x12 | 6.03 × 4 | 12 | 22.1 | 7.31 | −20 % | −24 % |
| W6x15 (this page) | 5.99 × 5.99 | 15 | 29.1 | 9.72 | — | — |
| W6x16 | 6.28 × 4.03 | 16 | 32.1 | 10.2 | +7 % | +10 % |
Deflection example
A simply supported W6x15 spanning 10 ft with a 10 kip point load at midspan deflects 0.43 in (E = 29,000 ksi, Ix = 29.1 in⁴). The L/360 serviceability limit for this span is 0.33 in — the shape does NOT pass this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W6x15 beam weigh?
W6x15 weighs 15 pounds per foot (22.3 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 300 lb and a 40 ft bar 600 lb.
What are the dimensions of a W6x15?
W6x15 is 5.99 in (152.1 mm) deep with a 5.99 in (152.1 mm) wide flange. The web is 0.23 in thick and the flanges are 0.26 in thick. Note the actual depth differs from the nominal W6 label — always design with the actual value.
What are the dimensions of a W6x15 in mm?
W6x15 is 152.1 mm deep with a 152.1 mm wide flange; the web is 5.8 mm and the flange 6.6 mm thick. In metric section properties: Ix = 1,211 cm⁴, Sx = 159 cm³.
How much does a W6x15 weigh in kg?
22.3 kg per meter. A 6 m bar weighs 134 kg and a 12 m bar 268 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W6x15?
About the strong axis, Ix = 29.1 in⁴ (1,211 cm⁴) with section modulus Sx = 9.72 in³. About the weak axis, Iy = 9.32 in⁴ and Sy = 3.11 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W6x15 or W6x16 — what does one size up change?
W6x16 is about 7% heavier (16 vs 15 lb/ft) but about 10% stiffer (Ix 32.1 vs 29.1 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