How to insulate with furnace in attic
I am currently looking to put forced air heating and air conditioning into my house. I am located in Long Island, NY in zone 4a, right on the border of 5a. We recently gutted the entire house down to the studs and we are replacing the whole heating system. We will be using gas heat. The contractor that I think we are going to go with is going to install a furnace in the basement for the basement and ground floor, and a furnace in the attic for the second floor. Well also have a blower in the attic for the air conditioning. The contractor told us that we should insulate the underside of the roof, instead of insulating the attic floor. I’ve heard a lot of conflicting arguments and I want to make sure that is the right thing to do. From what I gather, my three options would be to insulate the attic floor, insulate between the rafters, or build a small room to go around the furnace and insulate only that (in this case, would I also need to insulate the air handler for the ac unit). Any advice, recommendations, explanation, etc. would be highly appreciated.
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