How Do You Determine a Steel Beam Size?

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The size of a steel beam can be determined by measuring the web girth, height, flange width, and flange thickness. Once this data has been obtained, the beam manufacturer can be referenced – with its corresponding dimensions – in leading engineering manuals.

Publications from organizations such as the American Society for Engineering Education, American Society of Civil Engineers, National Academy of Engineering, and the American Institute of Steel Construction offer many helpful guides, charts, and manufacturer specifications to help accurately calculate beam sizes.

When recording beam dimensions, it’s important to maintain consistency with the system of measurement utilized; otherwise, discrepancies will occur when reviewing sources for the maker.

For example, if the flange width, height, and web girth are all measured in United States Customary Units, but the flange thickness is recorded in the International System of Units, the referencing materials will not precisely match the beam’s true size.