I've owned this home for about a year and this has always intrigued me. My 2-story home has a supply duct nearly pointing at a return duct in the center of the hall upstairs.

Two questions:

  • Would hot air even reach the floor in a setup like this?
  • Why are there four here? My assumption is in case all the bedroom doors are closed (even though the bedrooms themselves have return ducts in them), but why 2-and-2?

I'm going to have a HVAC specialist come out eventually anyway since the distant two rooms, as seen in the picture, are about 5 degree difference than the rest of the upstairs. This is partial to why I'm asking though, since it feels like the heat stops from this part of the hall and onward to the two additional rooms past it.

A couple of things to note

  • The upstairs is on a separate system than downstairs
  • The two "extra" rooms in the back (which are 5deg diff) do NOT have return ducts in them

Any insights would be helpful. Thanks!

upstairs hall

  • Indeed, it is a strange design
    – Traveler
    Jan 28, 2023 at 2:47
  • Well, heat would rise and be sucked up by the return, but cold would stay lower. The vent on the ceiling I'd certainly put a diverter on. But yes, odd indeed.
    – Huesmann
    Jan 28, 2023 at 14:12
  • Will need to find out if those two vents near the ceiling are for return. Return vents usually near the floor to suck cooler air. Up that high is where the warmest air usually is. Might be for AC use.
    – crip659
    Jan 28, 2023 at 17:54
  • That's not uncommon for a return scheme. Works in the summer and the winter with you doing nothing to the baffles that don't exist that you'd forget to open or close anyway.
    – Mazura
    Jan 28, 2023 at 19:18
  • "The two 'extra' rooms in the back (which are 5deg diff) do NOT have return ducts in them" - well, there's your problem right there, but "The upstairs is on a separate system than downstairs" so (I can't help you from here) you're going to need an "HVAC specialist come out eventually anyway".
    – Mazura
    Jan 28, 2023 at 19:34

1 Answer 1


Toe Kick Register/Diffuser ... 10" x 3" (?)

enter image description here

So that all the louvers point either way down the hall, not half at each adjacent wall.


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