3. A dwelling-house built before 6 November 1956 which is let under a private tenancy commencing after the introduction of the Order and which is not a prescribed dwelling-house and in respect of which there is no current certificate of fitness must be inspected by the district council to ascertain if it is fit for human habitation. Where a dwelling-house does not meet the fitness standard it is subject to rent control and an appropriate rent will be determined by the Rent Officer for Northern Ireland.