Outside stairways, fire escapes, fire towers, decks, porches, platforms, balconies, boiler flues and other similar projections shall be considered as part of the building and shall not encroach into the required space for yards or courts or occupied space. However, there shall be permitted certain exceptions to this requirement as limited and restricted hereinafter:
(a) Permitted exceptions for such projections shall be:
(i) One chimney or one fireplace, limited to not more than eight feet in length and projecting not more than 12 inches into the allowable side yard space.
(ii) Cornices, limited to not more than 16 inches in width, including the gutter.
(iii) Platforms, terraces, steps below the first floor level.
(iv) Decks, unenclosed porches or other ground-level, unenclosed projections not over one story in height.
(b) Limitations governing the projections, as so permitted, shall be:
(i) In a residential district, such excepted projections shall not extend more than 10 feet beyond the established front building line, shall not extend more than 15 feet into the minimum required rear yard, and shall not extend nearer than five feet to an interior side lot line or nearer than 30 feet to a side lot line abutting upon a street.
(ii) In a nonresidential district, such excepted projections shall not extend beyond the established front building line or into any required side or rear yard.