How to Use an Attic Fan?

How to Use an Attic Fan?

Do you have attic space lying idle, that you can convert into a comfortable living space?

Since the attic is at the top of the house, it gets direct sunlight from the roof that can make the space unbearably hot.

During the summer months, heat can build up in the attic and filter down to other parts of the home if the ventilation is poor. An attic fan works by pushing out hot air and drawing in cool air from outside. It helps the airflow in the attic become more balanced and consistent.

In the winter, when the windows are not open, the cold air rises and builds up in the roof and insulation in the attic. The attic fan helps balance the air quality, temperature, and humidity during the summer and winter periods. So get ready to install your attic fan and here is your guide to how to use it in an easy-to-understand walkthrough.

Getting the Most out of Your Attic Fan

Read your manual to see how your type of attic fan works.

To start:

  • Switch the fan to the highest setting and let it boot up. As it boots up, the slats will open and circulate the air
  • After booting up, switch it to the setting you want
  • Run the fan when the temperature is coldest. The good times are in the night around 10:00 and the early morning around 6:00
  • After the air cools, close the windows and blinds to keep the cool air inside

Benefits of Attic Fans

Studies show that attic fans can reduce energy use by as much as 50 percent.

Reduces Energy Costs

  • Attic fans help keep the attic cooler
  • The cool air can filter into other areas in the home, and reduce the use of air conditioning

Improves Ventilation

  • Attic fans allow cooler air to circulate in the attic.
  • They make the room more comfortable and improve the overall air quality. Heat creates moisture that can cause mildew or mold to grow.
  • The cooler air reduces mold and mildew build-up and protects the roof from rotting by heat build-up or mold.

Regulates the Temperature

The attic works in two ways:

  • It takes the hot air out through the vents
  • It pulls cool air inside to balance the humidity and temperature

Reduces damage from Winter Ice

Snow falling on the roof settles in the eaves and gutters and pile up. The ice can then re-freeze, forming clumps that can block the water from passing through. It then gets under the roof slats and leaks into the attic. Since attic fans move air around constantly; they help melt snow and ice that fall on the roof and protect the roof from leaks. Attic Fans and your Heating or cooling systems

Air Condition Units

You need to balance the use of your attic fan and other forms of energy in the home. If heat is allowed to build up unchecked, the attic fan can draw air from the air condition instead of outside. It will cause the unit to overwork to help expel the hot air and drive up your energy costs.


Similarly, if you operate a gas fireplace, your attic fan can pull stale air from the fireplace as well.

  • The attic fan may work in the opposite direction, by drawing the gases from the fireplace into the attic and other areas in the home
  • The carbon dioxide can cause harmful air to circulate


In hotter climates, you will need the attic fan more regularly than in cooler areas. Choose a more durable fan for hotter areas. If the temperature varies during the seasons, a more basic fan may suffice.

Maintaining your Attic Fan

The ventilators in the attic fan may wear down over time and cause the fan to make a humming or whining sound when in use. Loose screws may cause the fan to squeak or hum when in use. Switch the fan off, check the screws and give any loose ones a firm twist with a screwdriver.


Clanging or clicking noises in the fan suggests the blades may need adjusting. Re-balancing the blades will reduce noise and reduce the pressure off the fan to keep the air moving.


The fan’s bearings help keep the movements on the fan running smoothly.  They may wear down over time and cause friction when spinning. You can take the bearings out and replace them with new ones.

Which Attic Fan is Right for You?

The attic fan you choose depends on the amount of space and the type of roof you have.

The two main types are:

  • Roof mount
  • Gable Mount

Roof Mount Attic Fans

Roof mount fans usually rest close to the center of the attic roof and underneath the ridge at the back of the roof. You have to cut a hole near the top and place the fan into the open space. Position the fan on a metal or plastic base.

Gable Mount Attic Fans

Gable mount attic fans rest at the end of the house; and away from the direct wind.

Size Matters

Select an attic fan based on the size of your attic so that the fan can circulate the air adequately. Choose a smaller fan for small areas and a larger fan for more space. You may also need more than one fan for unusually large attic spaces.


Studies suggest that at least one square foot of ventilation for every 300 square feet of attic space is sufficient. Check the type of ventilation you have and measure the existing space. Be sure also to take the type of roof design into consideration.

You may need more or less venting, depending on how high or low the attic ceiling lies.


One factor in choosing an attic fan is energy efficiency.

  • Assess the overall energy use in your home.
  • Choose a fan that will not compete with other devices or increase the energy costs in the home.


An attic fan works by keeping your attic cool and regulating the overall temperature and humidity in the home. It pulls in cool air from outside and pushes out hot air through the attic vents. It reduces energy costs, improves air quality, and reduces mold and mildew build-up to protect the roof from rotting.

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