I just moved into a new house and I have that one room that always seems to be hot. It's on the 2nd floor of the house with the attic over it. The other 2 rooms on the 2nd floor are always a nice temperature.

The room is 23x20 with 9ft ceilings. There are 3 windows in the center of the back wall and the supply is centered over those windows.

There is no return at all in this room. I was wondering if I added a return would it help out with the heat. If I'm already adding a return then does it make sense to add another supply and if so where? Would it make sense to add a supply at the front and back of the rooms and the return in the middle (all in the ceiling)?

1 Answer 1


Adding a return and/or additional supplies may help. Adding a supply and a return would almost certainly help -- it might be overkill, but you could always close them off if needed.

The important point, however, is that this is a question of balance relative to other rooms. Knowing the best solution requires understanding the layout of your home and the sources of heating/cooling load. You mentioned this room has 3 windows; are they exposing this room to more solar heat gain than other rooms? Is it properly insulated? Are other rooms over-supplied? Is your home's entire cooling system undersized? All these factors should be considered before you make a change like adding ductwork. It could be that you need insulation, curtains, or even something as simple as closing vents in some other rooms.

There's a fair bit you might learn with some experimentation. Someone with HVAC expertise who can walk through your house would likely be able to evaluate quickly and suggest reasonable options. You could also have someone do detailed heat load calculations, but that may be overkill for your situation.

  • Thanks for the reply and all good questions. Yes, it gets more sun but it's always a little stuffier. It's also the room over the garage so most likely there is no insulation between the garage and the floor of the bedroom. The attic insulation if more than adequate. The other questions about balance I can't answer to say that the two A/C guys that came out said the units we had were fine. Then they went on to say the rooms over the garage are the worst.
    – JoshFink
    Aug 13, 2015 at 16:05
  • If it's really not insulated, air sealing and insulating the ceiling of the garage is probably the lowest-long-term-cost way to fix this problem. Heat from your un-conditioned garage is rising into that room. After insulation, it might still need more supply or other changes, but that's a great place to start. Aug 13, 2015 at 17:56
  • There perhaps could be insulation in there but the room over the garage always tends to be a little hotter. The problem is that it's cost prohibitive for me right now to take down the drywall ceiling, put in insulation, and then re-drywall.
    – JoshFink
    Aug 13, 2015 at 22:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.