Section 3(h) in Tamil Nadu Urban Land (Ceiling and Regulation) Act, 1978
(h)"land appurtenant" , in relation to any building means an extent of five hundred square metres contiguous to the land occupied by such building and includes,-(i)in the case of any building constructed before or under construction on the commencement of this Act with a dwelling unit therein, or(ii)in the case of any building proposed to be constructed with a dwelling unit therein and in respect of which the plan for such building has been approved by the appropriate authority before the commencement of this Act,
