W16x100 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W16x100 is an American wide-flange beam 17 inches (431.8 mm) deep with a 10.4 in (264.2 mm) flange, weighing 100 pounds per foot (148.8 kg/m) — that is what the "100" 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 in (431.8 mm) |
| Flange width bf | 10.4 in (264.2 mm) |
| Web thickness tw | 0.585 in (14.9 mm) |
| Flange thickness tf | 0.985 in (25 mm) |
Weight & Cross-Section
| Weight per foot | 100 lb/ft (148.8 kg/m) |
| 20 ft bar | 2,000 lb |
| 40 ft bar | 4,000 lb |
| Area A | 29.5 in² (190.3 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 1,490 in⁴ (62,018 cm⁴) |
| Section modulus Sx | 175 in³ (2,868 cm³) |
| Radius of gyration rx | 7.1 in |
| Moment of inertia Iy | 186 in⁴ (7,742 cm⁴) |
| Section modulus Sy | 35.7 in³ (585 cm³) |
| Radius of gyration ry | 2.51 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| W16x89 | 16.8 × 10.4 | 89 | 1,300 | 155 | −11 % | −13 % |
| W16x100 (this page) | 17 × 10.4 | 100 | 1,490 | 175 | — | — |
Deflection example
A simply supported W16x100 spanning 27 ft with a 10 kip point load at midspan deflects 0.16 in (E = 29,000 ksi, Ix = 1,490 in⁴). The L/360 serviceability limit for this span is 0.9 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W16x100 beam weigh?
W16x100 weighs 100 pounds per foot (148.8 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 2,000 lb and a 40 ft bar 4,000 lb.
What are the dimensions of a W16x100?
W16x100 is 17 in (431.8 mm) deep with a 10.4 in (264.2 mm) wide flange. The web is 0.59 in thick and the flanges are 0.99 in thick. Note the actual depth differs from the nominal W16 label — always design with the actual value.
What are the dimensions of a W16x100 in mm?
W16x100 is 431.8 mm deep with a 264.2 mm wide flange; the web is 14.9 mm and the flange 25 mm thick. In metric section properties: Ix = 62,018 cm⁴, Sx = 2,868 cm³.
How much does a W16x100 weigh in kg?
148.8 kg per meter. A 6 m bar weighs 893 kg and a 12 m bar 1,786 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W16x100?
About the strong axis, Ix = 1,490 in⁴ (62,018 cm⁴) with section modulus Sx = 175 in³. About the weak axis, Iy = 186 in⁴ and Sy = 35.7 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W16x100 or W16x89 — what does one size down change?
W16x89 is about 11% lighter (89 vs 100 lb/ft) but about 13% less stiff (Ix 1,300 vs 1,490 in⁴). Check deflection before downsizing — stiffness falls much faster than weight.
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