[abracadabra]

I live in Marion County where the codes prevent me from having an air duct installed. If you call the company who services your air conditioning unit, they will tell you what the parameters are. The floor of my lanai is not the same height as the rest of the house (you have to step down into the room) so that disqualified me from the outset.

As to what can be done, I had "Duette" shades installed. These are honeycomb style shades which keep out the heat in the summer and the cold in the winter. With a fan to keep the circulation going, the lanai is always pleasant. In winter a small electric heater takes off the morning chill.