(1) Whenever the Commissioner considers,-
(a) that any building or portion thereof is, by reason of its having no plinth or having a plinth of insufficient height or by reason of the want of proper drainage or ventilation or by reason of the impracticability of cleaning, attended with danger of disease to the occupier thereof or to the inhabitants of the neighourhood, or is for any reason likely to endanger the public health or safety, or
(b) that a block or group of buildings, is, for any of the said reasons, or by reason of the manner in which the buildings are crowded together, attended with such risk as aforesaid, he may by notice require the owners occupiers of such buildings or portions of buildings, or at his option the owners of the land occupied by such buildings or portions of buildings to execute such works or to take such measure as he may deem necessary for the prevention of such danger.
(2) No person shall be entitled to compensation for damages sustained by reason of any action taken under or in pursuance of this section save when a building is demolished in pursuance of an order made hereunder or so far demolished as to require re-construction, in which cases the corporation shall make reasonable compensation to the owner thereof.
(3) When any building is entirely demolished under this section and the demolition thereof adds to the value of other buildings in the immediate vicinity the owners of such other buildings shall be bound to contribute towards the compensation payable to the owner of the first named building in such proportion to the increased value acquired by their respective buildings as may be determined by the Commissioner.
(4) When any building is so far demolished under this section as to require reconstruction, allowance shall be made, in determining the compensation, for the benefit accruing to the premises from the improvement thereof.