Steel Beam Sizes Reference
Dimensional reference for common beam series. Verify exact dimensions with supplier mill tables for procurement.
Navigating beam section series across regions
Steel beam sections are organized into named series that differ by region, and understanding these series is essential for selecting the right section in any calculator or design. In North American practice (AISC), the primary beam shape is the W-shape (wide-flange), designated by nominal depth and weight per foot -- for example, W18x50 is nominally 18 inches deep and weighs 50 lb/ft. The S-shape (American Standard) and M-shape (miscellaneous) also exist but are far less common. In Australian and British practice, sections are designated as UB (Universal Beam) and UC (Universal Column), with dimensions in millimeters and weight in kg/m -- for example, 460UB67.1 is nominally 460 mm deep at 67.1 kg/m. European practice uses the IPE series (narrow-flange beams), HEA (light wide-flange), HEB (medium wide-flange), and HEM (heavy wide-flange), all dimensioned in millimeters.
A critical point that catches many engineers is that nominal depth does not equal actual depth. A W18x50 has an actual depth of 17.99 inches, which happens to be close. But a W14x730 -- the heaviest W14 -- has an actual depth of 22.42 inches, nearly 8 inches deeper than its "14-inch" name implies. This occurs because heavy W-shapes gain weight by increasing flange thickness (and therefore overall depth) while maintaining the same inner web-to-flange distance. The same phenomenon exists in all series: a 310UC158 is actually 327 mm deep, not 310 mm. For connection detailing, clearance checks, and floor-to-floor height calculations, always use the actual depth from the section property database, never the nominal designation.
The key dimensional properties for beam design are: overall depth (d), flange width (bf), flange thickness (tf), web thickness (tw), and weight per unit length. From these dimensions, section properties are derived: moment of inertia (Ix, Iy), section modulus (Sx, Sy, Zx, Zy), radius of gyration (rx, ry), and torsional properties (J, Cw). These derived properties drive every capacity calculation -- bending, shear, deflection, lateral-torsional buckling. Mill catalogs and section property databases are the authoritative sources for these values; handbook summaries are convenient but may be abbreviated or rounded.
Key points for section selection
When looking up or entering beam dimensions, keep the following in mind:
- Nominal depth is a label, not a measurement. Always use the actual depth (d) from the section database for connection design, clearance checks, and detailing.
- Not all sections are available in all markets. US mills roll a specific set of W-shapes; Australian mills roll a specific set of UBs and UCs. If you are designing in one region using sections from another region's catalog, confirm that the section can actually be procured. Imported sections may have longer lead times and higher costs.
- Section property source matters. Use the current edition of the relevant manual (AISC Steel Construction Manual, ASI Design Capacity Tables, CTICM/ArcelorMittal Orange Book). Properties can change between editions when remeasurement or re-rolling occurs.
- Flange and web thickness affect local buckling classification. Two beams with the same nominal depth but different weights have different flange and web slenderness ratios, which can change the section from compact to non-compact. This directly affects the available bending strength.
- Weight per unit length is approximate for self-weight calculations. The listed weight is a nominal value; actual weight varies within rolling tolerances (typically +/- 2.5%). For precise dead-load calculations on long spans, this tolerance can matter.
- Axis conventions vary by region. AISC uses X-X for the strong axis and Y-Y for the weak axis. Australian and European practice may label them differently. Always confirm which axis is which before entering Ix or Iy into a calculator.
For the full verification and documentation workflow, see How to verify calculator results.
FAQ
Why does a W14x730 have an actual depth much greater than 14 inches? W-shapes are grouped by nominal depth, which corresponds to the approximate depth of the lightest section in the group. As weight increases within the same group, the mill adds material primarily to the flanges, increasing flange thickness and therefore overall depth. The W14 group ranges from the W14x22 (actual depth 13.74") to the W14x730 (actual depth 22.42"). The "14" in the name reflects the group origin, not the physical dimension.
What is the difference between W-shapes, UB sections, and IPE beams? These are different section series produced in different regions. W-shapes (AISC) have relatively wide flanges compared to their depth. UB sections (Australian/British) are broadly similar to W-shapes but follow a different size progression with metric dimensions. IPE beams (European) have narrower flanges relative to their depth, making them lighter per unit depth but more susceptible to lateral-torsional buckling. Each series has its own section property tables and cannot be directly substituted without recalculating all capacity checks.
How do I know if a particular section is available in my market? Contact your steel supplier or fabricator. Mills publish rolling schedules and stock lists that vary by region. Common sections (W10-W24 in the US, 200UB-610UB in Australia, IPE200-IPE600 in Europe) are widely stocked. Very heavy or very light sections, and those from foreign series, may require special ordering. For preliminary design, focus on commonly available sections to avoid procurement delays.
How much do actual dimensions vary from handbook values? Rolling tolerances are defined in ASTM A6 (US), AS/NZS 3679 (Australia), and EN 10034 (Europe). Typical tolerances for depth are +/- 3 mm for sections up to 600 mm deep. Flange width and thickness tolerances are similar in magnitude. These tolerances are accounted for in the published section properties (which represent nominal dimensions), but they can matter for fit-up in connections, especially at beam-to-column interfaces. Fabricators work to these tolerances, so always allow for them in detailing.
Where can I find a complete section properties database? The authoritative sources are: the AISC Steel Construction Manual (US), the ASI Design Capacity Tables for Structural Steel (Australia), the SCI "Blue Book" or Tata Steel sections database (UK), and the ArcelorMittal section catalog (Europe). Many of these are available in digital form. The section properties database on this site draws from published open-source data, but for procurement and stamped design, always verify against the current edition of the relevant manual.
Related pages
- Section properties database
- Beam span table
- Beam capacity calculator
- Beam calculator
- Steel weight calculator
- Unit converter
- Tools directory
- Reference tables directory
- How to verify calculator results
- Disclaimer (educational use only)
Disclaimer (educational use only)
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