Unallocated Area

What is this line item?

Unallocated area in TestFit is areas that are not: NRSF, Common, Stair, Lifts or Amenity, but is still included in the gross area of the building. Unallocated areas typically show up in highly-constrained kit-of-parts database settings, or when units can't course with building massing perfectly. It is the black area in the plan below: