Correct person. Open floor plans that are either single story with attics or unfinished basements aren't so bad. Here in Florida we have a lot 2 story homes on slabs with very open first floors. The ductwork for the first floor is hidden beneath the finished 2nd floor and the finished ceiling of the first floor. Installation is limited to the spacing of the floor joists. What you end up having is a giant spider system. Balancing is laughable. What makes it worse is the beetus barges are so accustomed to having their own custom weather they fail to recognize how much BTU they had to their space because they are the size of a planet. On the residential side it's not a problem but in the commercial side you can't make anyone happy. It will be 75 in the room. The planet and a sweaty stinky mess bitching constantly, the normal human is wearing a sweatshirt. Hillsborough county schools was just in the local news. Teachers were complaining about not having A/C due to some failures. Take a guess how big the complainers were? Normal humans can handle an 80 degree room without passing out.