What size joist is required for a span of 14 feet using Southern Pine for floor joist with a 10 PSF dead load?

To determine the appropriate size of a joist for a given span, it is essential to consider the material type, span length, and load conditions. In this case, we are working with Southern Pine floor joists spanning 14 feet and carrying a dead load of 10 pounds per square foot (PSF).

The correct choice of a 2 x 10 joist is based on the structural capacity of different joist sizes to safely support the specified load over the given span. When using Southern Pine, a 2 x 10 joist has sufficient strength to handle the 10 PSF dead load across a span of 14 feet.

Joist sizing is determined by building codes and standard engineering practices, which take into account the species of the wood, permissible stress values, and the spans involved. A 2 x 10 provides adequate bending strength and deflection limitations for this application, while a 2 x 8 may be insufficient to safely carry the same load over that span, which could lead to excessive bending or failure. A 2 x 12 might be unnecessarily large for this load and span, resulting in increased costs. Similarly, a 2 x 14 is also more than what is required, making it impr