Clauses (g) and (q) defining "vacant land" and "land appurtenant" and sub sections (9) and (11) of Section 4 which have precedence in engaging our attention are set out below, but without the Explanation to sub sec tion (11), for it is not relevant for our purpose: "2(g) "Land appurtenant", in rela tion to any building means (i) in an area where there are building regulations, the minimum extent of land required under such regulations to be kept as open space for the enjoyment of such building, which is no case shall exceed five hundred square meters; or (ii) in an area where there are no building regulations, an extent of five hundred square metres contiguous to the land oc 509 cupied by such building, and includes, in the case of any building constructed before the appointed day and with a dwelling unit therein, an additional extent not exceeding five hundred square metres of land, if any, contiguous to the minimum extent referred to in subclause (i) or the extent referred to in sub clause (ii), as the case may be; 2(q) "Vacant Land", means land, not being land mainly used for the purpose of agricul ture, in an urban agglomeration, but does not include (i) land on which construction of a building is not permissible under the building regula tions in force in the area in which such land is situated; (ii) in an area where there are building regulations, the land occupied by any building which has been constructed before, or is being constructed on, the appointed day with the approval of the appropriate authority and the land appurtenant to such building; and (iii) in an area where there are no building regulations, the land occupied by any building which has been constructed before, or is being constructed on, the appointed day and the land appurtenant to such building.