I'm trying to figure out the best way to heat the second floor of my house. Its currently heated by a space heater but I want to get some kind of central heating system set up, but I'm not sure what set up makes the most sense for me.
The first floor of my house has forced air heat from a basement furnace, but the ductwork doesnt extend up to the second floor. I am planning on renting the second floor out to one of my friends. In light of this, all the subcontractors I've talked to have been advising me to just install a second furnace for the second floor. However, this doesnt seem to make a ton of sense to me. In terms of resale value, who is going to want to buy a house with two furnaces? Also, if I decide after a while that I dont want a roommate anymore then I am going to be stuck paying two furnace bills.
Couldnt I just use my existing furnace and extend the ductwork up to the second floor? Is that going to be more expensive than getting a second furnace? I want to get central air and upgrade my existing furnace eventually anyway. Would it make more sense to install a new furnace in the basement + central air, and extend the ductwork up to the second floor?