In any yard. Overhanging eaves, gutters, open terraces, marquees, flues, sills, lintels, pilasters, cornices, ornamental features, bay windows, awnings, open porches not enclosed by walls, screens, windows, or doors attached to the principal structure, providing they do not project more than three feet into the required yard. In addition, flag poles (maximum height of 30 feet), fences, light poles, and landscaping shall be permitted encroachments.