I'm looking to renovate my basement, and I've gotten mixed recommendations from HVAC specialist. I currently have 2 zones, 1 for the first floor and 1 for the second floor. The first floor is about 1,200sf. The basement space we're converting is about 800sf and will be entirely open. The one for the 1st floor is a 3 ton ac unit and 75,000btu furnace. I would like to ideally not have to add another zone for the basement as it seems a bit much. One person told me that they thought the unit could handle the entire space because the basement should be considered to heat and cool only half the amount I was actually trying to heat. I'm trying to come to a conclusion as to what we should ultimately do. Any suggestions and experiences would be appreciated. Thanks.