Gujarat Provincial Municipal Corporations Act, 1949
Notwithstanding anything contained in this Act, it shall not be lawful to erect any back-to-back buildings intended to be used as dwellings and any such building, shall for the purposes of this Act, be deemed to be unfit for human habitation: Provided that nothing in this section shall prevent the erection or use of a building containing several tenements in which tenements are placed back-to-back if in the opinion of the Commissioner the several tenements are so constructed and arranged as to secure effective ventilation of all habitable rooms in every tenement.