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Second floor hot

tony40 | Posted in General Questions on

Hi so I have a Chicago bungalow that we completely rehab we use spray foam on the second floor roof and exterior walls to keep it tight. We dormered were we put a full bathroom right in the middle of the house in front of staircase. My question is the second floor is always 10-15 degrees hotter how do I lower the temp. I don’t have a attic kids always complaining it’s hot even when I turn on the AC it’s hotter upstairs I had to install window units because it runs hotter upstairs. There has to be a solution so I can get it cooler and I could remove the window units also I want to be able only to use the whole house AC. Help bbq please

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  1. Jon_R | | #1

    You could adjust register dampers to provide proportionally more upstairs air flow and cooling in the summer. Also verify that all supply registers provide good mixing (lack of mixing is a key factor in stratification).

    1. tony40 | | #4

      Hi Jon
      Thanks I have closed all the ones in basement and half the ones on the first floor but still runs about 12-15 degrees hotter

  2. GBA Editor
    Martin Holladay | | #2

    Here is a link to an article you might want to read: "Keeping Cool in a Two-Story House."

  3. tommay | | #3

    Try cracking open the top half of a window upstairs to vent out the hottest air until it is gone. As Jon said, play with the vent dampers to see what works best. Remember, the cold air will settle downstairs forcing the hot air up. Where is your return air duct located?

    1. tony40 | | #5

      I have three returns one in each room and one in the hallway. Honestly I think your right about the return I think they need to be bigger to draw more of the hot air.

      1. tommay | | #6

        How high are the return ducts in each room? Are they on the floor or on the wall? Are they the same size or is the one in the hall larger? If so, perhaps it is drawing more than the bedrooms, especially if the bedroom doors are closed. Are the returns in the bedrooms blocked by anything? Perhaps try closing or covering the hallway return to create more pull in the bedrooms.

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