What is the maximum span for a cold-formed steel joist installed at 16 in. O.C for a 30 psf live load?

The correct answer regarding the maximum span for a cold-formed steel joist installed at 16 inches on center (O.C.) under a live load of 30 pounds per square foot (psf) is 21 feet, 5 inches.

When designing cold-formed steel joists, one of the critical factors to consider is the span of the joist in relation to the imposed loads it must carry, which includes live loads and dead loads. Cold-formed steel joists typically have manufacturer guidelines that help determine the allowable spans based on different load conditions.

For a live load of 30 psf, the joist's maximum allowable span can be calculated using the specifications provided by the manufacturer, which take into account both structural integrity and deflection limits to ensure safety and performance. The calculation involves considering the joist size, thickness, and the spacing between them. In scenarios where joists are spaced 16 inches apart, the spans provide a balance that allows for adequate strength while minimizing material usage.

21 feet, 5 inches is within the anticipated span range for this setup, making it the correct maximum span under the specified loading conditions. Each span measurement beyond this could lead to potential structural failure or excessive deflection, rendering it unsafe