When the following conditions are met, height limits may be increased up to 50% over those specified in § 150-22. Building height in excess of the height above ground level allowed in any district may be permitted, provided that all minimum front, side and rear yard depths are increased one foot for each additional foot of height. The following structures are exempt from height requirements, provided that they do not constitute a hazard to an established airport: television and radio towers, church spires, belfries, monuments, tanks, water and fire towers, ornamental towers, elevator bulkheads, chimneys, smokestacks, flagpoles, wind generators, silos, grain bins. These height exceptions shall not apply to any communications antennas or communications towers.