How to Replace a Bathroom Fan with No Attic Access

As an Amazon associate We earn from qualifying purchases.

A bathroom fan helps to eliminate moisture, humidity, and foul smell, expelling them out from the bathroom. 

Ever wondered how you can fix a new bathroom fan minus attic access? In this article, you will learn about the whole process until you replace a new fan. The entire process will require you to carry out two operations. There is removing the defective fan then fitting a new fan. This guide will give you the directions for the entire process in less than two hours.

How to Replace a Bathroom Fan with No Attic Access

Before we explain the process, you may wonder, why replace a new bathroom fan? Well, at some point, you might have encountered some mold-build up in the bathroom, a foul smell from the bathroom, and at times some bacterial growth.

All these issues are a result of excess moisture in the bathroom. When you have a faulty fan in the bathroom, it becomes hard to get rid of excess moisture.

But then, how can you replace a defective fan when you do not have attic access? It can be a challenging process for a beginner. However, read on to understand how to perform the entire procedure without attic access.

The Process of Replacing a Bathroom Fan with No Attic Access

Once it hits you that you need to replace a bathroom fan, the first thing to consider is the size and other equipment you should buy. That is why you should take the measurements to avoid inconveniences when installing a new fan. 

To measure accurately, remove the fan’s grill or cover. Inside, you will see two clips that you need to unfasten. Take note of the size of the duct and decide if it is necessary to cut the wall to easily access it. In most cases, ducts usually have a diameter of 3″ – 4″.

Layout Plan

Even though replacing a bathroom fan is an easy process, ensure you have everything in the correct sizes. Check the widths, lengths, and diameter. The new fan should fit in the bathroom with ease to simplify the entire process.  After having everything in order, assemble the tools you will require during the whole process. For instance, you will need

  • A new fan.
  • The keyhole saw.
  • Exhaust fan vent.
  • Fan housing.
  • Ductwork.
  • Duct connector.
  • Circuit Tester.
  • And an electrical wiring & wiring cover.

You might need other tools as well, depending on the size of your bathroom fan. The concept is to have everything in advance before starting.

Remove the old fan

As mentioned before, the process of replacing a bathroom fan begins with uninstalling the faulty one. The process includes:

  • Turning off the power and ensure there is no electricity passing through to avoid shocks
  • Have the fan cover removed if not yet removed
  • Remove the motor fan from its housing
  • Remove the housing fixed to the ceiling
  • Remove the electrical wiring along with the vent from the housing assembly by pushing the housing into the ceiling hole.
  • Remove the unfunctional housing from its place, then unfasten the duct.
  • Finally, clean the area, ready to install another bathroom fan. You can countercheck the measurements to be sure.

At this point, you have everything in place, ready to fix a new exhaust fan in your bathroom. Follow the steps below to achieve the entire process accurately.

Vent Installation

When you start fitting the functional fan, ensure the fan housing you bought fits well. Next, put the housing in place until it fits well. After fitting, check if you need to screw to the beams. At this point, you may require more logs on the beams to access the housing.

Removing the box cover from the fan you bought

If you do not have one, you can skip this step and then connect the wiring home via the hosing assembly. At this point, do not start any connections since you will be using the housing and the vent more often, hence more movements.

The duct Connection to the fan housing

You must ensure the flaps point downwards at this step since the air is supposed to leave the housing fan and not getting in. To fix a connector appropriately, you can use foil tape or zip to tie. Still, you can directly set the housing through the duct and have it into the bathroom’s ceiling.

Secure the housing to the ceiling joist

To fix the housing to the ceiling beam, fix a single side of the fan housing to the ceiling. Follow this step if your bathroom doesn’t have fast-install brackets fixed in place. They are light, hence no need to have them on both sides.

Begin the wiring process

When you have put the housing fan in place, it is time for wiring. Use the screws and nuts (allotted) to secure safe wiring. However, most companies produce fans with fast connectors on their cables on fan motors. While carrying out this process, take note to match respective wires when connecting.

Note: You might require additional wires if the fan you purchased has a light or humidity sensor. Again, consider using a grommet or a bushing to prevent sharp objects from damaging the wiring.

When you finish wiring accurately, fix the wiring into the wiring section or the ceiling

Sealing the gaps

At this phase, you are through with the wiring process. Seal the gaps using metal foil or caulk by applying some on the purchased bathroom exhaust housing edges. After sealing the gaps, fix the grill or the fan’s cover by fixing the clips in place.


Here, you have successfully installed the new bathroom fan. However, you need to see if it is working. It is now the right time to turn on the breaker. After turning on the breaker, click on the switch connecting the fan and see if it operates appropriately.

If you followed each step as explained, the fan is now fully functional and everything in place. As you can attest, the entire process isn’t that complex. You can comfortably remove an unfunctional bathroom fan and replace it with a new one at your home without an attic.