W14x342 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W14x342 is an American wide-flange beam 17.5 inches (444.5 mm) deep with a 16.4 in (416.6 mm) flange, weighing 342 pounds per foot (509 kg/m) — that is what the "342" 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.
Dimensions
| Depth d | 17.5 in (444.5 mm) |
| Flange width bf | 16.4 in (416.6 mm) |
| Web thickness tw | 1.54 in (39.1 mm) |
| Flange thickness tf | 2.47 in (62.7 mm) |
Weight & Cross-Section
| Weight per foot | 342 lb/ft (509 kg/m) |
| 20 ft bar | 6,840 lb |
| 40 ft bar | 13,680 lb |
| Area A | 101 in² (651.6 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 4,900 in⁴ (203,953 cm⁴) |
| Section modulus Sx | 559 in³ (9,160 cm³) |
| Radius of gyration rx | 6.98 in |
| Moment of inertia Iy | 1,810 in⁴ (75,338 cm⁴) |
| Section modulus Sy | 221 in³ (3,622 cm³) |
| Radius of gyration ry | 4.24 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| W14x311 | 17.1 × 16.2 | 311 | 4,330 | 506 | −9 % | −12 % |
| W14x342 (this page) | 17.5 × 16.4 | 342 | 4,900 | 559 | — | — |
| W14x370 | 17.9 × 16.5 | 370 | 5,440 | 607 | +8 % | +11 % |
Deflection example
A simply supported W14x342 spanning 28 ft with a 10 kip point load at midspan deflects 0.06 in (E = 29,000 ksi, Ix = 4,900 in⁴). The L/360 serviceability limit for this span is 0.93 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W14x342 beam weigh?
W14x342 weighs 342 pounds per foot (509 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 6,840 lb and a 40 ft bar 13,680 lb.
What are the dimensions of a W14x342?
W14x342 is 17.5 in (444.5 mm) deep with a 16.4 in (416.6 mm) wide flange. The web is 1.54 in thick and the flanges are 2.47 in thick. Note the actual depth differs from the nominal W14 label — always design with the actual value.
What are the dimensions of a W14x342 in mm?
W14x342 is 444.5 mm deep with a 416.6 mm wide flange; the web is 39.1 mm and the flange 62.7 mm thick. In metric section properties: Ix = 203,953 cm⁴, Sx = 9,160 cm³.
How much does a W14x342 weigh in kg?
509 kg per meter. A 6 m bar weighs 3,054 kg and a 12 m bar 6,108 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W14x342?
About the strong axis, Ix = 4,900 in⁴ (203,953 cm⁴) with section modulus Sx = 559 in³. About the weak axis, Iy = 1,810 in⁴ and Sy = 221 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W14x342 or W14x370 — what does one size up change?
W14x370 is about 8% heavier (370 vs 342 lb/ft) but about 11% stiffer (Ix 5,440 vs 4,900 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