Hot air rises. It's a fact. And this rising air makes the rooms on your second floor (often the bedrooms) less comfortable than desired. Tossing and turning in bed, fighting with the sheets, sweating through your nightwear— it's a common problem. Even with an air-conditioning system installed in your home, it's difficult to keep the second story cool in the heat of mid-summer without breaking the bank. With 2000 to 2009 being the warmest decade on record, according to the U.S. National Oceanic and Atmospheric Administration, homeowners must find new ways to keep their houses cool as the temperature continues to rise.
Block off the second story from the ground floor. To prevent the heat from rising, separate the two floors with a door or curtains so your efforts to cool the second story are not lost when heat from below rises to replace any cool air. If this separation isn't possible and you don't have air conditioning blowing cold air through the vents into the second story, close the second floor vents during heat waves to prevent additional warm air from rising though the ventilation system.
Buy a window air conditioner. Place it in a window facing the hallway or facing a door into the hallway. It's best if this window is located in a central, high-traffic space in the second story of your home for maximum cooling. Position a floor fan, turned on high, near the air conditioner, and point it toward the rest of the space to distribute the cool air further.
Install heavy, insulating curtains on all upstairs windows, and keep them closed. These will keep the heat from the sun out and the cool air inside.
Keep windows closed unless a cool breeze develops. When a cool breeze occurs, open windows on opposite ends of the second story to encourage the air to flow through the entire floor.
Run a dehumidifier upstairs to take the humidity out of the air.