If slab thickness increases from 4 to 5 inches due to heavier finish, which element must be reviewed?

• A. Fire sprinkler location
• B. Mechanical duct routing
• C. Concrete column dimension
• D. Drop ceiling height

Answer: (C)

When a heavier finish causes slab thickness to increase, the primary impact is on dead load carried by the structure. A thicker slab adds more self-weight, and that extra load must be transmitted through the floor system to the supporting frame. Because columns are the main elements that transfer loads from the slabs down to foundations, increasing slab weight directly affects whether the columns have adequate capacity. Therefore, the element that must be reviewed is the concrete column dimension to ensure it can carry the increased axial load and maintain the required safety and serviceability.

The other options are less directly tied to the change in slab weight. Fire sprinkler layout, mechanical duct routing, and drop ceiling height can be influenced by architectural or service constraints, but the immediate structural concern driven by heavier slab weight is whether the columns (and, by extension, the framing) have sufficient capacity.