In R9 through R12 Districts, other than R9A, R9X, R10A or R11A Districts, as an alternative to the maximum building heights set forth in Section 23-432, towers are permitted pursuant to the provisions of this Section. 

Above the maximum base height specified for the particular district, a tower with a maximum lot coverage of: 

1. 65 percent shall be permitted up to a height of 300 feet; and 
2. 50 percent shall be permitted above a height of 300 feet. 

For certain areas, additional tower regulations are set forth in Section 23-441.