Section 115A(1) in The Delhi Municipal Corporation Act, 1957
(1)Every building and every vacant land shall be assessed as a single unit:Provided that where portions of any building or vacant land are separately owned so as to be entirely independent and capable of separate enjoyment, notwithstanding the fact that access to such separate portions is made through a common passage or a common stair-case, as the case may be, such separately owned portions may be assessed separately.