According to the WELL v2™ feature N12 Optimization Food Production, a permanent and accessible space for food production is required to be at least 1 ft2 per regular occupant or 0.5 ft2 per student, whichever area is greater (up to a maximum of 1,500 ft2 and not less than 200 ft2). The area calculated is the actual growing area (vertical or horizontal) used for the production of food-bearing plants. For a commercial office building with 400 regular occupants, the minimum space required is 200 ft2.
References: = Standard | WELL V2 - Feature N12 Optimization Food Production