What is the maximum recommended spacing for 5/8-inch drywall installed on a wall at right angles to framing members?

When installing 5/8-inch drywall on walls that are perpendicular to the framing members, the maximum recommended spacing for the supports is indeed 24 inches. This spacing is suggested to ensure that the drywall is adequately supported and does not sag over time, which can lead to cracks in the joints and an unappealing finish.

Using 5/8-inch drywall is common in commercial applications due to its fire-resistant properties and sound attenuation capabilities. When the framing members are spaced further apart than 24 inches, the weight distribution of the drywall may become uneven, particularly if it is subjected to changes in temperature or humidity. The 24-inch spacing helps maintain the integrity of the installation, preventing issues such as the drywall bowing or becoming loose, which can compromise the overall quality of the wall.

Spacings closer than 24 inches can sometimes be used based on specific local building codes or particular building designs, but as a general rule for standard installations, 24 inches is the maximum recommended distance between the supports.