How Much Does It Cost to Install an Attic Fan?

Attic fans are a necessary part of every home. They help air circulate through the attic, removing heat and moisture, and preserving your roof’s lifespan. There are many different types of attic fans, as well as different sizes to accommodate a variety of home needs. This can mean that there is a range of different costs associated with this project.

Installing an attic fan costs, on average, $300 to $600 with the average homeowner spending around $500 on installing a gable mounted ¹ electric vent in a 1,000 sq.ft. attic with a thermostat ².

Attic Fan Installation

Pros and Cons

Attic fans have a lot of benefits for the user, but they aren’t the only type of attic ventilation that’s available. Therefore, it’s best to weigh the positive and negative attributes of adding a fan to your attic space.

Fan Size

Your attic fan should be sized to the square footage of your attic. For example, a 1,000 square foot attic needs to have a fan that can handle at least 460 cubic feet per minute of airflow. If your attic is poorly insulated, or you have problems with excessive moisture, you may need a larger fan to help account for the additional heat and humidity. Determining your attic fan size is done in part through the square footage, the height of the ceiling, the color of your roof, and the type of roof; more steeply sloped roofs can use smaller fans than larger fans. You can visit the Home Ventilating Institute to find out more precisely what size of fan you need for your attic.

Location

Attic fans can be installed in roughly two areas of the attic: the roof, and the gables or walls. Roof vents are usually installed along the ridge of the roof, and are often passive, meaning that they simply allow air to move in and out on its own. They’re relatively inexpensive, but can be more difficult and costly to install, because they may require additional or different types of shingles ³. This type of attic fan is usually installed at the same time as you have your roof reshingled so that the installation is seamless.

Gable or wall fans are generally installed in the same area where your attic likely already has a vent. This makes installation fairly simple and straightforward– you are simply swapping out the existing vent for a fan. Gable fans are designed to actively move air through your attic, pushing the warm air out and circulating it. They, therefore, require a power source, either electricity or solar energy.

In large attics, you may want to combine both a ridge cap vent and an attic fan to help keep the air moving adequately. Because roof fans are usually installed with the roof, however, many people choose to add a gable fan first to keep costs lower.

Fan Type

There are two basic types of fan installations: roof and gable. Roof fans install right through your roof, and are usually installed when you are having work done on the roof to get a good seal. Gable fans are installed in the wall of your attic and can take the place of an attic vent beneath the gable. Both come in several types.

Remember that wind-powered fans will have no additional costs for wiring or electricity, while solar and electric fans will have additional labor costs.

All fans will require cutting through the roof deck or attic wall. This may mean needing additional:

• Shingles ³: $100 for a square of shingles ³
• Siding: up to $100 depending on the size of the hole/repair
• Caulk ⁴: $4

To seal up the edges of the fan or vent once it is installed. This is why roof vents are usually installed by roofers while work is being down on the roof.

Labor

Passive, gable-mounted vents are able to be installed DIY without much difficulty. However, if you are mounting ¹ the vent or fan on your roof, or if you are installing an electric or solar-powered fan you will need to hire a professional installer to do the job.

• Roofers are the most qualified to install attic fans mounted ¹ on your roof line. Roofers charge between $45 and $75 per hour.
• If your fan is electric or solar powered, you will also need to hire an electrician to wire the fan to your home’s electric supply, or to properly mount ¹ and connect the solar panels. Electricians charge between $65 to $85 an hour.
• If you do not already have a space for the fan in your gables, you may also need to hire a carpenter to install the vent itself for around $70 an hour.

You should count on at least two hours of work to install the fan, and at least one hour to wire it properly.

Whole House vs Attic Fans

While they are both installed in your attic, there are some major differences between whole house fans and attic fans. An attic fan’s job is to keep air circulating through your attic space, removing heat and humidity from the attic so that it does not become superheated.

A whole house fan’s job is to cool your entire house by exchanging warm indoor air for cooler outdoor air. Whole house fans are generally larger and more costly - about $800 - both to purchase and to run. The less expensive models tend to be noisy, while the quieter versions often require you to use several in order to maximize the cooling, which in turn drives up the cost. Many people like to combine whole house fans with air conditioning units to help save on energy costs when it comes to cooling their homes. However, you would not want to run a whole house fan during the winter months, when an attic fan runs year round helping to prevent ice dams and moisture damage during the winter as well.

Enhancement and Improvement Costs

Automatic Shutters

Automatic shutters open and shut by themselves when the fan is running or not, respectively. This provides better ventilation, while helping to seal up the vent to prevent small rodents like bats from entering. They cost between $50 and $80 extra.

Dual-powered Fan

A dual-powered fan can use solar energy when the sun is out and electricity when it isn’t. This can save on energy bills without the drawbacks of solar fans, which may lose power on cloudy days. They cost $400-$600 on average.

Roof Cap

A roof cap is installed over your roof vent or fan, to help protect it from the elements and block animal entry. They cost around $50.

Thermostat

A fan with a thermostat ² can help you keep better track of attic temperatures, so you know how well the fan is working. Like with regular thermostats, they come in many forms, including manual, programmable, and with apps. They cost between $50 and $100 on average.

Humidistat

A humidistat functions like a thermostat ², but measures the humidity levels ⁵ in your attic. If you have had issues with moisture and mold in the past, a humidistat can help you stay on top of the moisture, so you can better control it. They cost from $50-$100.

Additional Considerations and Costs

• Installing a roof-mounted vent will require ridge-cap shingles ³ to be installed over it. This has an added cost of around $50 for the shingles ³.
• Installing a gable fan will also require caulk ⁴ to seal it in place. This can add $4-$8 for caulking ⁴ material.
• If you do not already have a vent in your gable that you are replacing with a fan, you will need to have one cut. This will add around $70-$100 to the cost of the installation.

Remodeling Terms Cheat Sheet

² Thermostat: A device that senses and regulates temperature by turning heating and cooling devices on and off

³ Shingles: A smooth, uniform, flat piece of construction material, available in a wide variety of materials and laid in a series of overlapping rows, used to cover the outside of roofs or walls to protect against weather damage and leaks.

⁴ Caulk: A chemical sealant used to fill in and seal gaps where two materials join, for example, the tub and tile, to create a watertight and airtight seal. The term "caulking" is also used to refer to the process of applying this type of sealant

⁶ Ridge vent: Ventilation opening in a sloped roof, installed at its pinnacle to remove moisture and warm air from the attic area

⁷ Lead: A naturally occurring heavy metal that is highly toxic to humans, and has been used in paint, gasoline, piping, and other applications