These off-street parking and loading regulations shall apply to all of the following cases:
(a) New Construction. The construction of a principal building or establishment of a new use.
(b) Change of Use. The change of use in an existing building to a use which requires more off-street parking or loading area than the previous use.
(c) Enlargement. The enlargement of a building or use with respect to floor area, seating capacity, number of dwelling units, or otherwise to create a need for an increase in the number of existing parking spaces.
(1) In the case of a building or use established after the effective date of this Ordinance, said building or use shall comply with the full parking requirements upon completion of the enlargement.
(2) In the case of enlargement of a building or use existing prior to the effective date of this Ordinance, additional parking spaces shall be provided on the basis of the enlargement alone if the enlargement constitutes an increase in square footage of less than fifty (50) percent. If the enlargement constitutes an increase of fifty (50) percent or more, the enlarged building or use shall then comply with the full parking requirements.