What is the total usable area (net area) of a building?

The total usable area of a building is the total net floor area of the building corresponding to the intended use of the building. The following coefficients are applied when calculating the net floor area:

• enclosed rooms = 1.00
• loggias = 0.75
• covered terraces = 0.50
• balconies, uncovered terraces = 0.25.