Final answer:
At least 50% of the required floor area of a room with a sloped ceiling must have a minimum ceiling height of 7 feet, to comply with common building standards.
Step-by-step explanation:
For rooms with sloped ceilings, the building code typically requires that a certain percent of the floor area must have a minimum ceiling height to ensure the space is livable and meets safety standards. Although the exact percentage can vary by jurisdiction, a common requirement is that at least 50% of the required floor area of the room must have a ceiling height of not less than 7 feet. This ensures that enough of the room is of a practical height for regular use.