How Does an Attic Fan Work?

An attic fan is usually installed in your attic ceiling or vent to maintain good ventilation in your attic, which in turn can be beneficial for the rest of the house.

How does an attic fan work? There are several steps involved that are important to understand to maintain its efficiency. We can look into these below.

Pushes Hot Air Out

Attics usually already have ventilation structures such as soffit vents that are situated below the eaves of the roof. These vents allow cool air to enter the attic, which then heats up and moves out through dormer windows or ridges.

An attic fan makes this process more efficient by improving the circulation that then causes most of the hot and musty air to leave the attic. This is particularly important for the attic since it directly takes in hot air that the roof absorbs.

This can thus help maintain a certain temperature inside the attic without causing overheating.

Draws in Cool Air

Once the attic fan pushes the hot air out, it requires something else to replace the air to maintain a balance. Thus, it draws in cool air from the soffit vents that then lower the temperature of the attic significantly.

This process continues to repeat itself as long as the attic fan remains on. As the cool air stays inside the attic, it warms up again and leaves the attic. It can particularly be helpful during summers when the air becomes too hot due to high temperatures.

This can then prevent the rest of the house from overheating as well.

Helps Cool Down the House

The cyclical process that the attic fan brings about can also help cool down the house indirectly. A lot of the heat in the house comes from the attic itself. By removing this hot air out, the attic fan can cool down other parts of the house as well.

This also helps support air conditioners inside the house that otherwise have to apply more effort to cool down the house. In the absence of hot air from the attic, air conditioners can focus on cooling instead of trying to deal with the hotter attic air.

In case the air conditioner stops working, the attic fan can act as a temporary backup, even if the cooling effect will not be as intense.

Improves Energy Efficiency

You can usually determine the temperature range within which you want your attic fan to work. Further, if there is a thermostat, you can enable the attic fan to turn on and off according to the temperature requirements.

Since the attic fan can cool down the attic, it can reduce the pressure on your air conditioner to run constantly. This can save energy and also reduce your monthly power bills to quite an extent.

Several attic fans tend to run on solar power, which reduces their dependence on electricity. This makes them even more energy-efficient and better for the environment and the rest of your house.

Maintains the Roof

Since the attic contains a large amount of hot and humid air in the house, it can lead to the growth of mold and mildew which can damage the structure of the attic and roof. If this makes it into the rest of the house, it can lead to health issues as well.

Further, since the warm air from the house can come into contact with the cooler air near your roof in winter, condensation can occur, leading to mold. By drawing the cool air in and expelling the warm air, the attic fan prevents the growth of mold.

This helps keep the roof in a good condition, thereby maintaining its durability.

Supports the Seals

It is important to ensure that your attic has good and tight enough seals between the roof as well as the rest of the house. It is necessary to avoid cracks and gaps as much as possible, as these could reverse the outcome of the attic fans.

With proper seals in place, an attic fan can work efficiently and in the right direction, supporting the function of these seals as well. Keeping your attic well insulated can help save energy and money while also contributing to the cooling process.

Without these seals, installing an attic fan may not be a good idea. In fact, it could end up leading to issues of combustion with different appliances around the house.

Frequently Asked Questions

Does the size of the fan make a difference?

It is important to ensure that the size of the fan is compatible enough with the attic itself. However, if the fan is too big, it might not be able to successfully replace the hot air with sufficient cool air.

Similarly, if it is too small, it might take much longer for it to expel the hot air out of the vents. This could then end up affecting the rest of the house as well.

Can I keep the fan running all the time?

Ideally, you shouldn’t keep the fan running all the time as this could end up using too much electricity, leading to higher bills. Therefore, if you only turn on the fan when you need it, you will be able to maintain the airflow while also saving some money and energy.

While you might need to run it more often during summer, using it minimally in winter can be sufficient to get rid of the excess heat and humidity.

Installing a thermostat or buying a fan with one can automatically turn the fan on and off based on the requirements of the attic.

Final Remarks

Through this guide, we have taken you through the ways in which an attic fan works and how it can help your house. We have also answered a few frequently asked questions to clear any remaining doubts.

If you notice any further issues with your attic fan or with your general cooling system in the house, you can contact a professional to look into the issue for you.