How to Cool a Two-Story House

Does your first floor feel like the Arctic while the second story feels like the desert? Trying to cool a two-story house can be a challenge. Science is often to blame with hot air rising and making upper floors feel hotter, and the construction of your home can also amplify the heat upstairs. To cool a two-story house effectively, it takes a little investigation to figure out the causes and some simple home cooling tips to keep you comfortable.

Many HVAC systems have dampers, which are platelike structures inside the ductwork, usually close to the furnace. Each branch leads to a different part of the house, carrying the cooled air to your rooms.

Adjusting the dampers opens or closes them fully or partially to control the airflow. You can partially close the dampers to areas that stay cold and open them fully to the upstairs rooms that stay hot. This can help balance the airflow and send more cold air upstairs for effective second-story cooling.

An effective way to help cool a two-story house is by adding insulation to prevent heat transfer. Proper home insulation helps your entire home feel cooler in the summer and warmer in the winter by helping to regulate the temperature. You can add blown-in insulation to walls that are already finished. Sealing leaks around windows can also help to better insulate the home and keep it more comfortable.

If your attic lacks insulation, it could be a big cause of your hot upper level. Your roof collects a lot of heat, which enters the attic. Since the second floor is right below the attic, that heat naturally seeps into those upper spaces. Increasing insulation can help keep your second story cooler.

Constant airflow helps you feel more comfortable, even if your upper floor has a higher temperature. Instead of using the "auto" setting for your HVAC fan, turn it to "on" so it runs all the time. Running your ceiling fan counterclockwise in the summer helps create a cool breeze in upstairs rooms. Attic fans can help cool the space above your second floor to decrease the temperature indoors.

Lots of everyday activities create heat that can make your upper floor feel even more uncomfortable. Drying your hair, drying clothes, cooking and running the dishwasher are examples. First-floor appliances and heat-generating activities can make the upper floor feel hotter since that heat rises. Limiting those activities, especially during the heat of the day, can help your upper floor feel more comfortable.

If your main HVAC system and fans aren't enough to keep your upstairs cool, consider adding supplemental cooling options. Installing a ductless air conditioner is an option that uses an outdoor unit and an indoor air handler with the option for multiple indoor handlers. This option lets you install an air handler in each room that needs extra cooling without connecting to the ductwork.

You can also use window air conditioners in the rooms that stay hot consistently. Choose a unit that's designed for the size of the room in which you're using it for air conditioning efficiency. This option is versatile since you can move it to different rooms, but installing a window air conditioner on the second story can be more challenging. A portable unit is often easier for an upper level.

Replacing an older HVAC system that can't keep up with your cooling needs can make you feel more comfortable and can lower your utility bills. A multizone HVAC system can help by letting you set a lower temperature upstairs to help it stay cool enough without making lower floors too cold. If your main unit still works well, it might not be properly sized for your home. Adding a second unit for your upstairs can help your entire home stay cool.