Section 33(c) in The Building Regulation in Respect of Lands Covered by the Calcutta Thika Tenancy (Acquisition and Regulation) Act, 1981
(c)When addition and alteration is proposed to an existing thika tenanted structure, the existing use of structure may be allowed to continue, not-withstanding the fact that the same is being used for purpose other than residential. No permission shall be granted in thika tenanted land where there is obnoxious/hazardous trade.
