What is the maximum percentage of floor area a minor accessory use may occupy while still adhering to major occupancy standards?

The correct answer is 10%. In the context of building codes and major occupancy standards, accessory uses are typically auxiliary activities that complement or support the primary use of a building. For a minor accessory use to be considered compliant under these standards, it must occupy a limited percentage of the overall floor area—10% is established as the threshold.

This limitation ensures that the primary function of the occupancy remains dominant and that the accessory use does not overwhelm or change the character of the major occupancy. By regulating the size of minor accessory uses, building codes maintain clarity in use classification, ensuring that safety, egress, and occupancy load calculations remain straightforward and manageable.

While other percentages like 5%, 15%, or 20% might seem feasible for certain contexts, they do not align with the standard maximum established in most building regulations. Thus, 10% is the balance that allows for some flexibility with accessory uses while still aligning with major occupancy standards.