If the boxes in a wall exceed 24" horizontally, what size must they not exceed in total for firestopping to be unnecessary?

When addressing the issue of firestopping in wall installations, it is essential to adhere to the guidelines set forth in building codes and industry standards. Specifically, when the boxes in a wall exceed a horizontal distance of 24 inches, their total area must remain within a certain limit to exempt them from requiring firestopping measures.

In this context, the maximum total area of the boxes should not exceed 100 square inches. This limit is established to minimize the risk of fire spread through such openings in the wall assembly. If the cumulative area of the boxes exceeds this figure, it indicates that there may be an insufficient barrier to prevent fire from traveling through the wall, thus necessitating firestopping.

Therefore, maintaining the total box area at or below 100 square inches is critical for compliance with safety standards and ensuring the integrity of the fire-resistive barrier of the wall. This limit is a well-understood requirement in electrical installations, highlighting the importance of considering both horizontal spacing and total area of electrical boxes within wall assemblies.