Update from Codes: the particular alley next to your address is 16 ft wide. Therefore, if you can identify (as best you can) the “middle” of the alley, then 8 ft towards your property line would need to be free of any vegetation encroaching on the surface, and any tree branches would have to allow for a clearance of 14 ft over the alley. If you'd like to discuss this with a codes investigator, you are welcome to call 727-893-7373 and we will arrange to have the investigator for your area meet with you to provide clarification. Thank you for your post.