Section 5 — Revision in fair rent in certain cases

(1) When the fair rent of a building or rented land has been fixed under section 4, no further increase or decrease in such fair rent shall be permissible for a period of five years:

Provided that an increase may be allowed in cases where any addition, improvement or alteration has been carried out at the expense of the landlord, and in the building or rented land which is in occupation of the tenant then at the request of the tenant:

Provided further that the decrease may be allowed in cases where there is a decrease or diminution in the accommodation or amenities provided.

(2) Any dispute between the landlord and the tenant in regard to any increase or decrease under this section shall be decided by the Controller.