Except as otherwise specifically provided by this chapter:

1.   No building or land shall hereafter be used or occupied and no building or part thereof shall be erected, moved or altered unless in conformity with the regulations herein specified for the district in which it is located.

2.   No building shall hereafter be erected or altered to exceed the height, to accommodate or house a greater number of families, to occupy a greater percentage of lot area, or to have narrower or smaller rear yards, side yards, front yards, inner or outer courts, than are specified herein for the district for which such building is located.

3.   No part of a yard or other open space required about any building for the purpose of complying with the provisions of this chapter shall be included as a part of a yard or other open space similarly required for another building.

4.   No building or buildings shall be erected, moved, altered, used or occupied in a district for purposes or uses other than are allowed herein for that district.