329. (1) Every person shall, within one month after the completion of the erection of a building or the execution of any such work as is referred to in section 317, deliver or send or cause to be delivered or sent to the [Municipal Commissioner] at his office, notice in writing of such completion, accompanied by a certificate in the form prescribed in the bye-laws signed and subscribed in the manner so prescribed, and shall give to the [Municipal Commissioner] all necessary facilities for the inspection of such building or of such work and shall apply for permission to occupy the building.
(2) No person shall occupy or permit to be occupied any such building, or use or permit to be used the building or part thereof affected by any work, until
(a) permission has been received from the [Municipal Commissioner] in this behalf, or
(b) the [Municipal Commissioner] has failed for twenty-one days after receipt of the notice of completion to intimate his refusal of the said permission :
Provided that an application under sub-section (1) may be made and permission of the [Municipal Commissioner] to occupy given in respect of part of a building also where the [Municipal Commissioner] is satisfied that part has become habitable.