How To Increase Airflow To Second Floor (Cool Upstairs With Ease)

Stuffy, stifling upstairs rooms are never fun. But how to increase the airflow to the second floor without spending more than you can afford?

Our expert advice will help you redistribute airflow and keep the upstairs cool in summer.

Bedroom with White Ceiling Fan

Why Is Upstairs Often Warmer?

The first thing you need to understand is why upstairs is so hot. There are several reasons this happens.

Rising Hot Air

One of the reasons airflow to the second floor isn’t as effective is because of air density. Like all other particles, air’s properties alter with temperature. Cold air is naturally dense and heavy, causing it to sink. This works in your favor if you want to cool off the first floor of your home.

Conversely, hot air is light and rises above cold air, leaving you with a hot, stuffy upper story in your home.

Hot Roof Heats from Direct Sunlight

Darker shingles, like black or dark grey, absorb light. As they absorb sunlight, they trap heat, and that heat warms the space underneath it. Typically, that’s your second-floor ceiling.

If you want to cool the second floor of the house, start by lightening those shingles.

Ductwork, Insulation, and Seals

Another common reason for airflow not cooling your second story is faulty ductwork. The ducts in your home are supposed to redistribute cool air throughout the house. But if one is blocked or broken, that might not happen.

Similarly, a broken seal or insufficient insulation might mean that your second story doesn’t trap cool air as effectively as downstairs.

If your air conditioning works downstairs but not upstairs, examining the ducts and installation is the place to start.

How to Increase the Airflow on Second Floors (Ways to Make It Cooler)

There are several ways to get more air conditioning upstairs. These 2-story house air conditioning tips will help you cool upstairs bedrooms.

Clean or Change Your Air Filter

The first thing to try when you want to cool the upstairs of a two-story home is to replace your air filters. Damaged, broken, or clogged air filters can cause cold air to stop before it reaches the second floor. When that happens, you end up with a freezing first story and a stifling second floor.

changing an AC filter

Get the Most Out of Air Registers

Another way to stop cold air from going downstairs is to ensure the vents aren’t blocked. If they are, you will experience significant difficulty cooling off the upstairs.

Blockages don’t have to be internal. Objects can also affect your vents by absorbing the cool air they emit. Perform a visual inspection and make sure your air registers are unobscured by:

  • Furniture
  • Long curtains
  • Carpets

Make Sure Windows And Doors Are Closed

Another way to get the air conditioning to the second floor is to ensure your windows and doors are closed.

It’s natural to want to open the windows in stuffy rooms, but if you do that, all the cold air escapes through the windows.

Close Your Curtains

This is another way to cool down the second story. Drawing the curtains blocks the sunlight and stops rooms from overheating. This is especially effective in small rooms.

Since cold air naturally sinks, the incoming sun-warmed air displaces it. Note that if you have light-colored or thin curtains, this may be less effective at cooling the upstairs. Consider using heavier, darker curtains in summer to keep your attics and second floor overheating.

Redo Your Insulation

People associate insulation with winter because it stops the cold air from getting in and keeps their houses warm. But insulation can work the other way around, too. When it’s hot out, insulation traps the cold air your air conditioning generates and stops the warm air from coming indoors.

If your insulation is damaged, your house can’t block that hot air as efficiently, and your air conditioner struggles to combat it. Damaged insulation also causes cold air to escape the ducts and go outside. So you still spend money cooling down the house but can’t feel the result because the insulation can’t do its job.

Switch Lights Off but Fans on

You’ve now closed your windows and drawn the curtains, but it’s still too hot to sleep upstairs. Another way to cool down the second floor is to turn all the lights off. On long sunny days, you don’t need overhead lights anyway. And they generate heat, as well as light.

As you turn your lights off, switch on any overhead fans. They’ll keep the cold air moving, and that stops the cold air from sinking back down to the basement.

If you don’t have an overhead fan, plugging in and switching on a free-standing fan will also help increase airflow to the second floor.

Replace Your Air Conditioner

Finally, if you try everything else and nothing works, it’s time to replace your air conditioner. Sometimes an air conditioner breaks down, and as it deteriorates, it loses its efficacy.

If and when you do, don’t forget to follow the rest of our advice. That way, you’ll get the most out of your new system and increase airflow to the second floor with minimal effort from the air conditioner.

Window Type Air Conditioner Unit in a Bedroom with Socculent Plants

Why Is My AC Not Cooling the Upstairs Area?

Various things combine to make your air conditioner work. When it’s functioning properly, it generates cold air by pushing it through ducts and into your air registers. When these are unimpeded, the vents distribute cold air throughout your home.

If that’s not happening, it may be because:

  • Vents are blocked
  • Ductwork is faulty

You might also lose cold air to open windows or doors, so you must close them before switching on your air conditioning.

People Also Ask (FAQ)

Is it better for an AC to cool upstairs or downstairs in homes?

Hot air rises. That means that when it’s hot out, you want your air conditioning to focus on cooling upstairs.

Does it cost more to cool a two-story house?

Sometimes. How much you spend on air conditioning is a matter of preference. There are low-cost solutions that allow you to prioritize which parts of the house you cool down.

How do I balance upstairs and downstairs thermostats?

To increase airflow on the second floor, try setting the thermostat on ground level two degrees higher than the upstairs thermostat. That encourages cold air to flow upwards and redirects warmer air downstairs to even out the temperature.

How do I even out the temperature in my house?

If upstairs is hotter than downstairs, create climate zones. Doing this helps set temperatures for different parts of the house and redistributes the cold air, increasing airflow on the second floor without turning your ground floor subarctic.


There are various reasons your airflow on the second floor may be imperfect. But, there are an equal number of ways to cool down upstairs bedrooms and make the second story bearable again.

With luck, one or more of these tips boosts airflow on the second floor and gives you back the cool evenings you’ve missed.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.