How It Works

Select the work to be done
Let us know what project you need help with and when you need it done - we'll match you with the right pros for the job.
Compare matched pros
Verify pro credentials, read reviews, ask questions, discuss availability, and request project estimates.
Complete your project
Hire the pro that's right for you and your budget. After the project is complete, let your community know how it went.
Powered by

The Home Depot

Bathroom Fan Installation Guide

Pro Referral > Home Guides > Bathroom > Bathroom Fan Installation Guide
Bathroom Fan Installation Guide

All of use the bathroom to wash away the dirt and grime accumulated throughout the day. It needs to be a clean and dry place that will help us to unwind and relax even as we wash off the sweat and stress encountered during the past few hours or even longer. Moreover, the humidity and heat from a bathroom can spread to other parts of your home, attract cockroaches, lead to mold and mildew formation, and so on.


The least expensive way of ensuring that your bathroom is well-ventilated and dry is to install a bathroom fan. This will ensure that the humid and hot air in trapped in your bathroom is directed outside, making it much more pleasant to use.

  1. According to the Alliance for Healthy Homes, installing bathroom fans prevents the spread of cockroaches, mold, and mildew.

    1.Healthy Option

    According to the Alliance for Healthy Homes, installing bathroom fans to reduce humidity can prevent the spread of cockroaches, mosquitoes, mold, and mildew all of which can trigger asthma and other respiratory illnesses. And no one wants cockroaches around. They are about as unsettling to see as any creature.

  2. 2.Nine Steps to Install a Bathroom Fan

    Follow these nine steps to install a bathroom fan and make your home a healthier place to live in. Since installing a bathroom fan is not very simple, you can also retain the services of a contractor listed online to do the work for you. Make sure you take some due diligence with them though.

  3. 3.Cut a Hole

    Cut a Hole

  4. 4.Attach the Fan

    Now place the venting fan over the hole you have cut after attaching a 4-inch, 90 degree duct elbow to it at the outlet port. The duct should be aimed straight up and can be secured to the fan using foil duct tape. Set the fan into the ceiling between the joists and screw it tightly to the joists. For this you will need to extend the brackets until they reach the joists.

  5. 5.Flexible Duct

    Now fix the flexible duct over the duct elbow. Secure it firmly to the elbow using foil duct tape. Foil duct tape will last longer than fabric duct tape as it disintegrates much more slowly.

  7. 6.Electrical Connection

    Now feed the electrical cable through the connector and screw the connector tight. This will secure the cable.

  8. 7.Sidewall Duct Hole

    Now you need to select a spot on the sidewall of the attic through which the flexible duct can release the air from your bathroom. Cut a hole in the side wall to match the measurements of the flexible duct. The hole should be less than six feet from the vent fan and between two wall studs. You can use a four-inch hole saw to cut this duct hole.

  9. 8.Fix Wall Cap

    Now attach the wall cap to the outside wall over the duct hole you have cut. Ensure that the sides are properly sealed.

  10. 9.Attach Exhaust Duct

    Next you have to enter your attic again and attach the flexible duct or exhaust duct to the wall cap from inside. Use foil duct tape to secure the attachment.

  11. 10.Final Wiring

    Now that everything is in place enter the bathroom, remove the blower motor carefully by unscrewing it. Remember to save the screws since you will need them again. Remove the wiring container’s cover and expose the wires. Carefully connect same colored wires from your electrical outlet to the bathroom fan’s wires. Now cover the wiring container and replace the blower motor as well.


    If you have extra wires at this stage, you could call up a reliable and experienced electrical contractor to check the wiring.

  13. 11.Grille

    Once the motor is in place you need to cover it with the plastic grille. Hold the grille against the blower motor and attach it to the fan using the slotting wires.


    By installing a bathroom fan you will be able to reduce humidity levels in your home making it a healthier place for your family. Lower humidity levels are not only more comfortable but prevent the spread of mold and mildew and creatures such as cockroaches and mosquitoes.

Find Pros

Get your home project started today with help from Pro Referral’s qualified network of pre-screened and background-checked professionals available in your neighborhood.

Get Expert Advice

Submit your toughest home improvement questions to our knowledgeable experts and receive free personalized solutions, product recommendations, how-to advice, and more–all within 48 hours or less.