What method is used to calculate gross square footage needed?

The correct method for calculating gross square footage is to divide the net square footage by an efficiency ratio, which accounts for the relationship between net and gross areas in a building. The efficiency ratio reflects how much of the building’s total area is usable as net square footage versus the total space that includes circulation, structural elements, and other non-usable areas.

When you divide net square footage by an efficiency ratio of 0.75, you are effectively recognizing that 75% of the total floor area is usable for the intended purposes, leading to a gross area that is larger than the net square footage due to these additional factors. This calculation helps in determining how much overall space is required to achieve the desired usable area while considering design and operational efficiency.

In this context, other methods mentioned would not accurately reflect the relationship between net and gross square footage according to standard practices in architecture and building design.