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W27x84 — Dimensions, Weight & Section Properties

American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual

W27x84 is an American wide-flange beam 26.7 inches (678.2 mm) deep with a 10 in (254 mm) flange, weighing 84 pounds per foot (125 kg/m) — that is what the "84" 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.

W27x84: cross-section drawn to scale from the AISC dimensions (d 26.7, bf 10, tw 0.46, tf 0.64 in)h 26.7b 10tw 0.5 · tf 0.6 in
W27x84: cross-section drawn to scale from the AISC dimensions (d 26.7, bf 10, tw 0.46, tf 0.64 in)

Dimensions

Depth d26.7 in (678.2 mm)
Flange width bf10 in (254 mm)
Web thickness tw0.46 in (11.7 mm)
Flange thickness tf0.64 in (16.3 mm)

Weight & Cross-Section

Weight per foot84 lb/ft (125 kg/m)
20 ft bar1,680 lb
40 ft bar3,360 lb
Area A24.7 in² (159.4 cm²)

Section Properties (strong / weak axis)

Moment of inertia Ix2,850 in⁴ (118,626 cm⁴)
Section modulus Sx213 in³ (3,490 cm³)
Radius of gyration rx10.7 in
Moment of inertia Iy106 in⁴ (4,412 cm⁴)
Section modulus Sy21.2 in³ (347 cm³)
Radius of gyration ry2.07 in

Compared with the neighbouring sizes

Shaped × bf (in)lb/ftIx (in⁴)Sx (in³)Δ weightΔ Ix
W27x84 (this page)26.7 × 10842,850213——
W27x9426.9 × 10943,270243+12 %+15 %

Deflection example

A simply supported W27x84 spanning 43 ft with a 10 kip point load at midspan deflects 0.35 in (E = 29,000 ksi, Ix = 2,850 in⁴). The L/360 serviceability limit for this span is 1.43 in — the shape passes this quick check.

Calculate with your own span and load →

Frequently asked questions

How much does a W27x84 beam weigh?

W27x84 weighs 84 pounds per foot (125 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 1,680 lb and a 40 ft bar 3,360 lb.

What are the dimensions of a W27x84?

W27x84 is 26.7 in (678.2 mm) deep with a 10 in (254 mm) wide flange. The web is 0.46 in thick and the flanges are 0.64 in thick. Note the actual depth differs from the nominal W27 label — always design with the actual value.

What are the dimensions of a W27x84 in mm?

W27x84 is 678.2 mm deep with a 254 mm wide flange; the web is 11.7 mm and the flange 16.3 mm thick. In metric section properties: Ix = 118,626 cm⁴, Sx = 3,490 cm³.

How much does a W27x84 weigh in kg?

125 kg per meter. A 6 m bar weighs 750 kg and a 12 m bar 1,500 kg — handy when ordering US shapes from metric suppliers.

What is the moment of inertia of a W27x84?

About the strong axis, Ix = 2,850 in⁴ (118,626 cm⁴) with section modulus Sx = 213 in³. About the weak axis, Iy = 106 in⁴ and Sy = 21.2 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.

W27x84 or W27x94 — what does one size up change?

W27x94 is about 12% heavier (94 vs 84 lb/ft) but about 15% stiffer (Ix 3,270 vs 2,850 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