What building efficiency ratio should be used for a double-loaded corridor design?

A double-loaded corridor design typically includes a central corridor with rooms or units accessible from both sides, effectively maximizing the use of space and allowing for efficient circulation within the building. The building efficiency ratio, which reflects the proportion of usable area to the total area, is crucial in calculating the effectiveness of the design.

In the case of a double-loaded corridor, a building efficiency ratio of 0.75 is often adopted because this design allows for optimal use of the corridor space while ensuring sufficient room for circulation and amenities. This ratio signifies that 75% of the total building area is devoted to usable space, while the remaining 25% encompasses circulation, mechanical spaces, and other non-usable areas.

This level of efficiency is commonly seen in institutional, multi-family, or office buildings featuring double-loaded corridors, as it balances the need for access and movement with the maximization of the net usable area. Hence, 0.75 accurately reflects the efficient design of such spaces.