Where I live heating is used 7 months and cooling 3 months of the year. I am planning to install a new HVAC system in my house with a return in every room except the kitchen and bath. I understand that registers at the floor rather than ceiling would be best for heating but it would be easier to install ductwork in the attic rather than the basement. Is there a clearly noticeable difference between having the heating registers in the ceiling or in the floor? Thanks.
Either one works so long as you have enough air volume and throw. Duct in the attic does increase the heating and cooling load of a system though.Keeping it in a conditioned space is always the best plan.