In more cases than not a 3 ton ac with the ducts in the attic has a ton or so of load that s just from the location of the ducts in the attic and the associated duct gains leakage etc.
Ac ducting without attic.
Iv conditioned attic and more.
Your attic is the most susceptible room in the house for this.
Another way your ducts lose energy reducing your hvac system s effectiveness and costing you extra money is when hot or cold energy from outside air literally forces its way through your ducts changing the temperature of your air.
If your home does not have an hvac system and you plan to add one you will need to have new ductwork.
I lowered soffits around room perimeters.
Your ducts won t be exposed to the elements.
Ii lowered ceilings in hallways.
The remaining 2 tons of capacity is at least 1 5x oversized for the actual 1 load.
The air ducts for a central hvac systems are typically located above a home in the attic or upper crawl space or underneath a home in the space between the foundation and the floor so you don t see them unless you have cause to replace them.
Iii special trusses that create space below the unconditioned attic.
If ductwork is covered with insulation without an additional vapor barrier there is not enough air flow inside to dry sweating ductwork.