Interior side yards shall be provided in accordance with the regulations hereinafter indicated. Interior side yards shall be unobstructed from ground level to sky, except as allowed in section 5-3-9 of this title. All accessory buildings which are attached to principal buildings (as attached garages) shall comply with the yard requirements of the principal buildings. However, on a lot of record which is less than one hundred feet (100') in width, each side yard shall be not less than ten percent (10%) of the lot width, but in no case less than five feet (5'); or if the width of such a lot shall be less than one hundred fifty feet (150') but shall be one hundred feet (100') or more, each side yard shall be not less than fifteen percent (15%) of the lot width. (Ord. 89-8, 7-24-1989)