W24x131 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W24x131 is an American wide-flange beam 24.5 inches (622.3 mm) deep with a 12.9 in (327.7 mm) flange, weighing 131 pounds per foot (195 kg/m) — that is what the "131" 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.
W24x131: cross-section drawn to scale from the AISC dimensions (d 24.5, bf 12.9, tw 0.605, tf 0.96 in)Dimensions
| Depth d | 24.5 in (622.3 mm) |
| Flange width bf | 12.9 in (327.7 mm) |
| Web thickness tw | 0.605 in (15.4 mm) |
| Flange thickness tf | 0.96 in (24.4 mm) |
Weight & Cross-Section
| Weight per foot | 131 lb/ft (195 kg/m) |
| 20 ft bar | 2,620 lb |
| 40 ft bar | 5,240 lb |
| Area A | 38.6 in² (249 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 4,020 in⁴ (167,324 cm⁴) |
| Section modulus Sx | 329 in³ (5,391 cm³) |
| Radius of gyration rx | 10.2 in |
| Moment of inertia Iy | 340 in⁴ (14,152 cm⁴) |
| Section modulus Sy | 53 in³ (869 cm³) |
| Radius of gyration ry | 2.97 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|
| W24x117 | 24.3 × 12.8 | 117 | 3,540 | 291 | −11 % | −12 % |
| W24x131 (this page) | 24.5 × 12.9 | 131 | 4,020 | 329 | — | — |
| W24x146 | 24.7 × 12.9 | 146 | 4,580 | 371 | +11 % | +14 % |
Deflection example
A simply supported W24x131 spanning 39 ft with a 10 kip point load at midspan deflects 0.18 in (E = 29,000 ksi, Ix = 4,020 in⁴). The L/360 serviceability limit for this span is 1.3 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W24x131 beam weigh?
W24x131 weighs 131 pounds per foot (195 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 2,620 lb and a 40 ft bar 5,240 lb.
What are the dimensions of a W24x131?
W24x131 is 24.5 in (622.3 mm) deep with a 12.9 in (327.7 mm) wide flange. The web is 0.61 in thick and the flanges are 0.96 in thick. Note the actual depth differs from the nominal W24 label — always design with the actual value.
What are the dimensions of a W24x131 in mm?
W24x131 is 622.3 mm deep with a 327.7 mm wide flange; the web is 15.4 mm and the flange 24.4 mm thick. In metric section properties: Ix = 167,324 cm⁴, Sx = 5,391 cm³.
How much does a W24x131 weigh in kg?
195 kg per meter. A 6 m bar weighs 1,170 kg and a 12 m bar 2,339 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W24x131?
About the strong axis, Ix = 4,020 in⁴ (167,324 cm⁴) with section modulus Sx = 329 in³. About the weak axis, Iy = 340 in⁴ and Sy = 53 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W24x131 or W24x146 — what does one size up change?
W24x146 is about 11% heavier (146 vs 131 lb/ft) but about 14% stiffer (Ix 4,580 vs 4,020 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