Ordinary projections. Ordinary projections of balconies, entry platform coverings, fireplaces, cornices, fly rafters, eaves, gutters, sills, bay windows, belt courses, chimneys, flues, buttresses and ornamental features may project not more than 24 inches from an exterior building wall into any required yard area, provided the projection does not violate the covenants of any deed or deeds to the property upon which the projection is made. Such projections shall not, however, be permitted along the Main Street frontage of any structure or for any permitted living quarters above an accessory garage.