Types of attic fans & what type do you need?

If you are in search of an attic fan you may have come across different types of them. There are mainly 4 types of attic fans based on their mounting location and source of power.

The most common types of attic fans are;

  • Roof mount attic fans
  • Gable mount attic fans
  • Solar attic fans
  • Electric attic fans

Roof mount attic fans

Roof mount attic fans are those attic fans designed to be installed on the roof of the house. In many cases, the attic of the house may not have a gable so the only place you can install a power attic ventilator would be the roof.

Picture of a roof mount attic fan

A roof-mount attic fan comes with a metal or plastic flashing and a dome, all combined together as a single unit. It is installed by cutting a hole through the roof. This type of attic fans are usually smaller in size compared to the gable mount type. This is to make sure that the fan fits within the rafters of the house as cutting through the rafters for the fan’s installation can be difficult and problematic. Even though there is no building code dictating the distance between the rafters of a roof, usually this value is 12, 16, or 24 inches and the majority of the roof mount models fall within the 16-inch diameter size.

The fan is installed parallel to the roof. The fan, the mounting, the dome, and all the other parts come as a single unit so the installation is pretty straightforward and easy for a professional but it can be tricky if you are not experienced. If you are DIYing, make sure to use a water sealant under the flashing to ensure that it stays leak-proof.

Gable mount attic fans

Gable mount attic fans are those attic fans designed to be installed on the gable of the house. They are installed in a position vertical to the ground and parallel to the gable. These fans vary in size, and you can find some large-capacity models as there are not many size restrictions when it comes to gables.

Image of a gable mount attic fan
Image of a gable mount attic fan

Installation of these types of attic fans is easy if you already have a gable vent in position. If not, this may take more time than roof mount installations. However, since there is no risk of leaking this is safe for new DIYers to try.

While every part of a roof attic fan comes as a single unit, the shutter for the gable attic fan needs to be bought and installed separately. As mentioned before, these fans can have high airflow rates. So if you have a large attic with gable vents, these types of attic fans are a good choice.

Electric-type attic fans

It is not that hard to guess what electric attic fans are; they run on electricity. Based on the source of power there are two types of attic fans; electric and solar. The majority of the attic fans available in the market are electric. They are much cheaper to buy compared to solar fans. The average Wattage of attic fans is less than 300 so it won’t cost you a fortune to run them.

Picture of a simple electric attic fan
Picture of a simple electric attic fan

Electric attic fans are much powerful when compared to solar type attic fans. They can move more volume of air and are available across a wide range of CFM airflow ratings.

Solar type attic fans

Solar attic fans run on solar power. They come with a solar panel which needs to be installed on the roof. They are generally very costly to buy. They are thought to be cost-effective but in practice, it will take a long time before you recoup the initial expenses. Solar attic fans are available in gable and roof mount types. But roof mount ones are more popular because they can be easily installed where they get the most exposure from the sun. When it comes to gable mount solar fan models the installation of the solar panels is limited to the roof areas around the gable.

Picture of a solar attic fan
Picture of a solar attic fan

Since this type of attic fans run on solar power they are not very efficient when it is cloudy. Also, they don’t work at night. However, these drawbacks don’t have much practical significance since attic fans are meant to work only on the hottest times of the day. There are some hybrid models that can run on electric power when solar energy is below a threshold.

One drawback of this type of fan is that they have low airflow. Solar panels can’t generate as much power as a direct electric connection, so the airflow ratings of solar attic fans are limited. However, if you have a small attic, these fans are a good choice. Another problem is control. Electric fans can be controlled via thermostats, wall switches, or remote control but there are no such controls for solar attic fans. In fact, they will start running as soon as you show the solar panels to the sun, even before installation, so take care when you install these fans.

You can read more about solar attic fans here.

Gable mount vs roof mount attic fan – Differences

Here is a quick comparison of gable mount and roof mount attic fans;

Roof mount attic fanGable mount attic fan
Installed on the roofInstalled on the gable of the attic
The fan runs parallel to the roofThe fan runs vertically to the ground
High CFM rated models are limitedPlenty of high CFM models
Easy to install but need expertiseTakes longer to install but takes less expertise

Electric vs Solar attic fans – Differences

Here are some of the main differences between an electric attic fan and a solar attic fan;

Electric attic fansSolar attic fans
Runs on electricityRuns on solar power
High CFM fansLimited to low CFM ratings
Works day and nightDoesn’t work during the night
Consistent performance throughout the dayPerformance limited to the availability of sunlight
Cheaper to buyCostly to buy
Cheaper to runCosts nothing to run
Can be controlled via thermostats, switches, or remote controlNo control options
Comes with shorter warranties for most modelsComes with longer warranties

What type of attic fan should you buy?

When it comes to the type of attic fan to buy, there are no one size fits all rule. If your attic doesn’t have a gable then your only option is buying a roof mount fan. If you have gable vents and a large attic area, then a gable fan is more suitable. If the attic area is smaller, even if you have gable vents, a roof mount fan is a better choice as it can draw air through the gable vents as well.

Choosing between a solar and electric attic fans is more difficult. Solar attic fans make economical sense only if you use them long term. They do not come with any sort of control switches so if you are a control freak ( 🙂 ) choose an electric fan. Also if your attic is big and needs more airflow electric attic fans are the best choice.

Charles John

A novice DIYer who learns about home ventilation. I am a mechanical engineer and have a basic knowledge of HVAC systems but I learn continuously to make myself the best blogger in that space.

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