What Is an Attic Fan? (Explained for Beginners)

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If you own your home, it’s essential to invest in and understand attic fans. They help you manage the temperature in your entire house.

What is an attic fan?

An attic fan is a electricity or solar-powered exhaust fan that helps to cool your attic and house. An attic fan pulls the hot air out of your attic and releases it outside. This helps to keep your attic cooler, reduce the workload on your AC unit, and save money on your energy bills.

Keep reading to learn about the 10 types of attic fans, what they do, who needs them, and which ones you should buy.

What Is an Attic Fan? (Easy Definitions)

Graphic of house and attic ventilation—What Is an Attic Fan?
Image by author via Canva—What Is an Attic Fan?

An attic fan is also called an exhaust fan or ventilation fan. Homeowners ask me a lot of questions about attic fans.

I love answering the questions to help clear up confusion and simplify the information they may have found elsewhere.

For example, what are all the main types of attic fans?

Types of Attic Fans

There are 10 main types of attic fans. It’s helpful to know the types so that you can choose the perfect one for your house or building.

Types of attic fans:

  • Whole house attic fan
  • Gable mount attic fan
  • Roof-mounted attic fan
  • Electric attic fan
  • Plug-in attic fan
  • Solar attic fan
  • Garage attic fan
  • Smart attic fan
  • Old style attic fan
  • Large attic fan

What Is a Whole House Attic Fan?

A whole house attic fan is a supplement for air conditioning (AC). Homeowners used them to cool their houses long before modern AC existed.

Larger attic fans can cool a house in three minutes—while using 90% less electricity than AC units.

Like other attic fans, you mount a whole house fan in your attic.

There are three types of whole house attic fans:

  • Standard—A large diameter fan is the most common because it is the most budget-friendly and available. Installation can be a bit tricky and get expensive fast, depending on your attic. You’ll probably need some extra insulation (i.e. insulation box) in colder temperatures to reduce heat loss.
  • Inline—These fans circulate less air than standard attic fans, but they are also easier to install. You may need more than one of them to cool your entire house.
  • Insulated—An insulated door fan includes a door that automatically opens when you turn on the fan (and closes when the fan is off). An insulated whole house attic fan is great for people who live in colder climates or have an older home because they trap more heat than standard fans. They are also usually quieter. The downside is that they move less air.

What Is a Gable-Mounted Attic Fan?

A gable-mounted attic fan is mounted in a gable wall with a gable vent.

The gable wall is the triangular wall that’s created when the pitched roof of a house meets the side of the house. A gable vent is a ventilation system that you install in a gable wall.

If there is not already a gable vent, you’ll need to build one.

What Is a Roof-Mounted Attic Fan?

Roof-mounted attic fans require you to make a hole in your roof, install the fan, and then seal the openings.

They are efficient and powerful, but they also require a much more complex installation process.

For it to work correctly, you’ll need to cut a hole and mount the fan on a sheet metal or plastic base. This procedure can take quite a bit of time.

The fan is encased in a weatherproof box that protects it from outside elements like rain and snow. The box also keeps out debris, large pests, and small bugs.

You might also hear a roof-mounted attic fan called a ceiling attic fan.

What Is an Electric Attic Fan?

An electric attic fan is powered by electricity.

It is the most common type of attic fan. The fan is generally connected directly to an electric circuit (through wiring).

With this type of fan, you can use a thermostat to manually or automatically switch the attic fan on or off. Personally, I prefer the automatic system so that I can set it up and not think about it.

Like any other fan, you should probably check on your attic fan routinely throughout the year.

What Is a Plug-In Attic Fan?

You can also plug an attic fan into a nearby power outlet. This is an alternative to directly wiring the attic fan into your main electrical system.

As you might guess, it’s a much simpler process.

For direct wiring, you may need to hire an electrician. As long as there is already an outlet in your attic, you can probably handle plugging in the attic fan yourself.

What Is a Solar Attic Fan?

A solar attic fan is powered by the sun.

It’s the most environmentally friendly attic fan because it uses the sun’s energy instead of electricity, which also saves you money on your electric bill.

Solar attic fans typically get mounted on the roof of your home.

If you’re thinking about buying a solar attic fan, here are some factors to consider:

  • Does it come with a thermostat?
  • Does it come with a humidistat?
  • Does it include hybrid electric capabilities?
  • Does it work on your type of roof? (some only work on shingled roofs)
  • Can it be remotely controlled?
  • Does it come with a protective screen?
  • Is it portable?
  • How does it handle the rainfall and other weather conditions?

What Is a Garage Attic Fan?

A garage attic fan is an attic fan installed in the ceiling of your garage.

This is a good way to keep your garage cool. Garage attic fans vent to your attic (and/or outside). These fans help you manage both the temperature of your garage and your attic.

If you live in very hot or humid climates, garage attic fans can really make a difference.

What Is a Smart Attic Fan?

A smart attic fan is controlled by an app that you can install on your smartphone. You can also connect the fan to your smart device (computer, smart speaker, etc).

A smart attic fan is usually more expensive than other standard attic fans.

Before you purchase a smart attic fan, make sure you know how the app handles power outages. Some apps save and restore your fan settings while others do not.

What Is an Old Style Attic Fan?

Back in the 1970s, people referred to old-fashioned attic fans as “helicopter” fans.

These vintage fans were loud and many people jokingly said that they sound like a helicopter.

Modern attic fans are much quieter.

What Is a Large Attic Fan?

A standard size attic fan is ‎approximately 16 x 16 x 10 inches.

Therefore, anything much larger than this is technically a “large” attic fan. Attic fans come in many sizes to match the size of your attic.

Generally, the size needed for an attic fan is about 700 CFM for every 1000 square feet of attic space. If you have a steep or dark roof, you’ll need a bigger size.

For very large spaces, you may even need more than one attic fan.

What Does an Attic Fan Do?

An attic fan pulls the hot air out of your attic.

The soffit vents you should have already installed in the eaves draw outside air into the attic through the fan to replace the hot air that was removed.

This causes your attic to suck cooler air from outside, which will in turn cool your home.

As the attic fan draws outside air into the attic, it vents stale, hot air out through attached dormers.

In this manner, the attic fan also helps to keep the attic cooler, which in turn keeps the shingles and roofing materials from overheating and deteriorating prematurely.

Check out this 2-minute video that visually shows you how attic fans work:

YouTube Video by QC Manufactoring—What is an attic fan?

What Does an Attic Fan Not Do?

An attic fan will probably not cool your entire home by itself. At least, not as well as modern AC.

It’s not a magic solution.

You should still use air conditioning (or even fans) to cool your home when it gets too hot. Attic fans work best when combined with other methods of cooling, like air conditioning and insulation.

Who Is an Attic Fan For?

An attic fan is for anyone who owns a house or building with an attic. The ventilation system is helpful whether you live in a hot climate or a cold climate.

The size of your house also doesn’t matter.

You can use attic fans in a small, medium, or large house. In bigger houses, you will likely need to install more than one fan.

Who Is an Attic Fan Not For?

An attic fan is not for anyone who doesn’t own a house or building with an attic.

If you don’t have an attic, then there’s no need to install one.

You would simply waste money.

Pros and Cons of an Attic Fan

Let’s quickly go over the major pros and cons of an attic fan.

Check out this table of advantages and disadvantages:

ProsCons
Energy efficientRequires some energy
Roof lasts longerExpensive installation
Cools your houseLess cool than AC
Prevents moldRequires maintainance
Back up for ACMight break down
Attic Fan Pros and Cons

Attic Fan Brands

There are many brands that make attic fans. As with any product, some brands are better than others.

List of popular attic fan brands:

  • Grainger
  • ILiving
  • ‎Broan
  • Master Flow
  • Quiet Cool
  • Costco
  • Jet fan
  • Kennedy Solar
  • Kool-o-matic
  • Cool Attic
  • Lamanco
  • Leslie Locke
  • Nutone
  • Maxx Air
  • Panasonic
  • Solaro Aire
  • Pr3x
  • Remington
  • Hunter

Best Attic Fans

The best attic fan is one that fits in your budget, lasts many years, and does what it promises.

Here is a table of my recommendations:

PurposeBest Attic Fan
Best Overall Attic FanQuietCool 40 Watt Solar Roof Mount Attic Fan
Best Solar Attic FanSolaro Aire
Best Roof Mounted Attic FanBroan 358 Roof Mount 120-Volt
Best Gable Mounted Attic FanQuietCool Smart Fan (AFG SMT PRO-2.0)
Best Smart Attic FanQuietCool Smart Fan (AFG SMT PRO-2.0)
Best Whole House Attic FanQuietCool QC ES-7000 Classic Line Model
Coolest Attic FanMaxxAir IF24UPS IF24 Industrial Exhaust Fan
Quietest Attic FanCool Attic CX1500 Ventilator
What is the best attic fan?

Final Thoughts: What Is An Attic Fan?

Although many people don’t think much about an attic fan, they can prove very useful.

You can purchase them from Amazon, manufacturer websites, and many home improvement stores (Lowes, Home Depot, etc).

What to read next:

Sources

Energy.gov
Bob Vila