I live in an older home that didn’t come with existing ductwork.
It also is built really flimsy.
Have you ever looked into ductwork installation? It requires the HVAC contractor to rip down walls and the ceiling in order to install the 8 inch metal ducts. It is very invasive, messy and hard on the house. It is not recommended for older homes like mine. I knew my house couldn’t take it. I wanted something that would provide heating and air conditioning through every room in the house. I wasn’t all that interested in a ductless mini split or heat pump though. The multiple indoor air handlers with thermostats didn’t appeal to me. I then found that high velocity HVAC systems are perfect for older homes. They use ductwork, but it is half the size and made of a flexible material. Rather than rip down the wall, a few holes are drilled to thread the ducts inside of the slat. The heating and air then has a network to move all throughout the house. The system works really well. Consider the name high velocity. It means high speed or high power. The heating and cooling system can quickly whip that treated air throughout the ducts to raise or lower the temperature. Rather than wait 30 minutes for the AC to finally achieve the temperature on the thermostat, it only takes a few minutes. The installation and the functionality of this system is what has really appealed to me. I think when my current HVAC unit dies I am changing over to high velocity.