(1)Where any building or any part thereof is within the regular line of a public street and in the opinion of the Municipality, it is necessary to set back building or a part thereof to the regular line of such street, the Chief Officer of the Municipality shall, by a notice served on the owner of such building in the Municipality shall, by a notice served on the owner of such building in accordance with the provisions of this Act, require him to show cause within such period, as may be specified in the notice as to why such building or part thereof, which is within the regular line acquired by the Municipality.