How many linear feet of cove molding are needed to trim the ceiling of a foot by foot family room?

To determine the linear feet of cove molding needed for a foot by foot family room, you need to calculate the perimeter of the room. For a room that is 10 feet by 10 feet, the perimeter is 40 feet (10 + 10 + 10 + 10). Therefore, you would need 40 linear feet of cove molding to trim the ceiling.