Adding a ventilation fan to your bathroom is a common and effective method of circulating air within that small space. Ventilation fans help remove humidity from the space, which can lead to water damage and mold spore growth.
The average cost to install a bathroom ventilation fan is about $375, and most spend $50 to $500. However, what you will pay depends on if you are replacing an existing fan, the type of fan, whether ducting needs to be installed, if roof drywall, roof, or siding repair is necessary, and whether you DIY or hire a professional for installation.
Replacing an Existing Ventilation Fan
Replacing an existing fan is reasonably inexpensive since new electrical or ductwork is usually not needed. When you can hook into the current electrical box, and the fan is the same size, it might require only an hour or two to install.
Even when you DIY, you should hire a licensed electrician to install the electrical wiring if you’re not comfortable with this type of work. This tie-in should take less than an hour, so expect to pay the minimum charge for a service call and materials.
Size & Type of Fans Available
There are generally two sizes. For small bathrooms that are about 5′ x 8′ you can use a fan rated at 70 – 90 cubic feet per minute (CFM). Larger bathrooms should use a 100 CFM rated fan.
Another consideration is the sones rating. Sones measures the exhaust fan noise level. A smaller sones rating means a quieter but a more expensive fan.
A typical ceiling or wall exhaust fan will cost the buyer $75 to $125, adding a light will cost $100 to $175, and adding a light and heater will cost around $125 to $250. There are even some fans with bluetooth speakers integrated into them.
Adding Air Ducts
Venting a fan into the attic could allow mildew and mold growth long-term, so it should be ducted outside. When putting in a new exhaust fan, you might need to add air ducts to whisk out the fumes and humidity. HVAC technicians usually charge $50 to $100 per hour and can complete the job in one or two hours.
Another factor that many do not consider about installing a fan is the repair to surrounding drywall or ceiling/wall coverings when complete.
You might need to replace and paint some drywall. This repair could be a DIY project but to find out how much professionals charge, check our drywall repair cost guide.
There are several inexpensive enhancements you can add to your fan’s installation, such as noise reduction, a speed control switch, and humidity sensors. These enhancements add a little to the installation costs but will increase your quality of life and should prevent additional repairs down the road.
A noise-dampener could add $50 to $100 to your installation cost but might be necessary for light sleepers in a small home with thin walls.
Speed Control Switch
Speed control switches might add another $20 to $50 when added as part of the installation.
A humidity sensor can detect high levels of humidity and turn the fan on to exhaust it. Installers recommend this enhancement, which typically adds $50 – $75 to your project.
Window Ventilation Fans
Although it is best to add a permanent exhaust fan to your bathroom, you may want to use one that sits in the window, plugs into an outlet, and can be moved if necessary. Window units are often less costly to install, and the units usually cost just $20 to $60.
A window unit could be more costly to install if a receptacle needs to be installed closer to the window. The average cost of adding an electrical outlet is $200.
DIY or Professionally Installed Bathroom Fan
Adding a bathroom fan is not a complicated project for those with some DIY skills and tools. However, to ensure it gets safely installed, the electrical wiring must be left to a licensed electrician, or at the very least, gets inspected by one, before you close the ceiling or wall.
When you do not have the skills or tools, and you want a quick, clean installation, it might be wise to hire a professional.
Typically, when the installation is not included as part of a bathroom renovation, then hiring a handyperson to install your bathroom ventilation fan is less expensive than hiring a general contractor because they usually have less overhead, and they might not require a license. However, a licensed, bonded, and insured contractor is generally the safer choice.
Check with the local building inspector’s office to determine if you need a building permit, which usually adds $20 – $100 to your project.
All pricing information on this page is based on average industry costs, and is subject to variance for project-specific materials, labor rates, and requirements.