(in Buffalo NY)

We just about finished remodeling our master bedroom. Everything insulated, drywalled and we're living in it.

Now that the winter is upon us, we're already finding this room to be colder then the rest of the bed rooms upstairs.

I have a clear shot from the basement to the attic via a old clothing chute that's being closed off. In the basement, the opening for the chute is just feet from the furnace.

Can I run a new duct from the basement, up the cavity, into and across the attic and down through the ceiling of this room?

Can I put a vent in the ceiling of the bedroom or must it be in the wall / baseboard ?

We're talking 20 feet max through the floors into the attic and another 20 feet across the attic into the bed room. Will I have a lot of heat loss at that distance?

I should mention its a brand new 97% efficient Lennox furnace sized properly for the house.

  • Usually heat vents are near the floor, because heat rises. You may find that your head is warm, but your feet are cold if you put the vent in the ceiling.
    – Tester101
    Oct 27, 2011 at 14:06
  • Yes, I understand heat rises, cold settles. For the sake of not destroying new walls would it be an "ok" compromise? I'd rather put it in the ceiling than no where at all. To go into a wall means I need to open up the family room wall; if it was drywall, fine; its plaster and lath; not a breaker, but i'd rather not patch it. its unstable as it stands I find.
    – lsiunsuex
    Oct 27, 2011 at 16:53
  • You could put a ceiling fan over the vent in the ceiling to blow the warm air down. Oct 27, 2011 at 18:37

2 Answers 2


I can't think of any reason not to run the duct through any open path. If the duct goes into any uninsulated space, you'll need to have the duct itself insulated. And on a vertical run between floors, I like to have a fire block between the floors, but that may not be code in a single family dwelling. Be sure to block any drafts, run a vapor barrier, and insulate where the line goes from an interior wall into the attic space.

  • Yes, for sure. My concern is just if I'd be causing any problems by going through the attic. Vapor barrier, insulation around it and I may even build a plywood box around it so it doesn't get damaged from using the attic for storage space.
    – lsiunsuex
    Oct 27, 2011 at 16:57
  • The lack of a fireblock between the furnace and the bedroom seems like a concern. Nov 2, 2011 at 19:48
  • 1
    @AlexFeinman As best I know, that's not a requirement in the US in a single family dwelling. You can have a furnace in an unfinished space with no fire wall at all. As a requirement, the fire blocking only comes into code when you're in a multi-family structure, or with tall walls to slow fire inside the wall. That said, there's nothing wrong with putting it in there.
    – BMitch
    Nov 2, 2011 at 19:58

I lived in a house with a substantial quantity of the duct work running through the attic. You want to insulate the duct work very, very well. It only takes a little bit of heat in your attic to cause ice damning, which can result in a lot of water damage. If you are using that insulated flex ducting, I would still go ahead and throw more insulation on top. Be extra careful about air intrusion around where the ductwork goes through the ceiling.

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