Best Bathroom Extractor Fan 2018

Bathroom Fan Buying Guide


Bathroom exhaust fans are an important part of every homes ventilation system. They’re easy to use and definitely often ignored. They help to reduce humidity in the air and make for a more comfortable bathroom environment.

So why then are bath exhaust fans not used more often?

Homeowners who rarely use bath fans do so because traditionally they were loud and annoying. The idea of taking relaxing bath with a loud buzz of a fan doesn’t sit well with the typical homeowner.

Instead manufacturers have come up with a pretty simple solution - quieter fans.

These fans promise to be quieter while at the same time just as efficient. This is important because the typical shower can produce a pint of water in the form of humidity. 

Excessive moisture in the bathroom can quickly become a big problem.

Damp air can linger in the home for hours after a shower or bath. Over time the moisture can lead to peeling paint and warped doors. Also because of the humidity is the perfect environment for mould growth.

To minimize the problem all the moisture damage the best practice is to specify a bath extractor fan for the bathroom which is

  • quiet,
  • properly sized to the room’s dimensions.

We take a look at the best bathroom fans on the market today.

We discuss what you should look for in a good quality fan and we provide bathroom fan reviews of the models we think are the top-rated models in the market.

Buying a Bathroom Venting Fan in a Nutshell

A bathroom ventilation fan adds comfort and improves the air quality by venting moist air to the outside. When shopping for a fan you need to know what size is needed for your room.

A fans ability to move air is rated in CFM's or cubic feet per minute. The bigger the room, the higher the CFM rating needed.

For example, let's say the room has an 8 foot ceiling if the square footage is less than 50 square feet, look for a CFM rating of 50. For larger rooms, look for 1 CFM per square foot.

When considering the amount of noise a fan will make look at the fans Sones rating.

A rating of 1.5 or less is considered a quiet fan.

If you are installing a fan for the first time you'll also need to consider ducting options. Top storey room fans can be vented through the attic and out the roof or sofits. Ground floor fans will need to be vented out of the side of the house.

There also many options you can consider. Fans are available with lights, heaters, night lights and timers. And they come in a variety of styles and finishes.

Key considerations when choosing a fan


Bathroom vent fans have a rating based upon their ability to move air. This rating is measured in cubic feet per minute or CFM.

The Home Ventilating Institute has produced general guidelines for evaluating the CFM rating you will need to install in your bathroom.

home ventilating institute

These guidelines state that for bathrooms that have a floor area of up to 100 square feet, you should expect to require a fan that is 1 CFM per square foot. If the size of the room is less than 50 square feet, then we recommend you go for a fan with a minimum CFM of 50 or more.

If your bathroom comes in with a floor area that is over 100 square feet then the calculation switches. Now, you should be looking at the fixtures in the room and using these to base your calculation upon.

You should be allowing 50 CFM for each of a standard tub, a shower and a toilet. If you have a whirlpool tub, or a garden tub or some other form of jetted tub then you should allow 100 CFM for each.

  • As an example, if you have a bathroom that is measured 10 ft by 8 ft then you would need to be looking for a bathroom fan that has a rating of 10 x 8 = 80 CFM, or better.

Alternatively, if your bathroom had the measurements 12 ft by 13 ft, then this exceeds 100 square feet and you would switch to looking at the fittings within the room.

  • Say, for example, your bathroom has one toilet, one shower and one tub. Then each of those fixtures would require a 50 CFM fan, so the whole bathroom would require 3 x 50 = 150 CFM rated bathroom fan (or above).

One other item to note. You must ensure that these is at least a 5/8ths inch gap between the bottom of the bathroom door and the floor. This is important as it enables fresh air to flow into the room to replace the air being vented out by the fan.


If you are replacing an existing vented fan then you should make sure you know where the ducting vents to.

The fact is that there a lot of older fan installation where the ducting has not been properly fitted, indeed, some have not even been vented even to the outside. This may sound strange, as the dumping of warm moist air into an attic or other cavity can have serious implications, but the fact is it happens more than you might think.

We recommend you consider replacing the venting as well as the fan, for peace of mind, if nothing else.

Equally, if you are installing a new bathroom fan then you look for metal ducting, if possible a single unit to route the moist air from the fan to the outside. The vent should be positioned so that it vents as directly as possible outside. This may be through the roof cavity, or if you are not on the upper storey, through a wall.

On the outside, you will also need a weather tight vent canopy complete with a grill to ensure little critters can't get in. By doing this, you assure yourself that you will effectively remove the warm moist air out of the bathroom meaning the environment within is more healthy and comfortable.

Noise level

The old days of noisy bathroom fans are, thankfully, very much a thing of the past. The top rated bathroom fans have incorporated significant improvements in their noise levels. This applies both to new fans and the upgrading of existing fan installations.

The measurement of fan noise is measu​red using units of measurement called Sones.

In brief, 1 Sone is the loudness of 1kHz tone at 40 dB. This may not actually be that helpful, so to give you a better idea 1 Sone is roughly the loudness that can be attributed to a modern refrigerator. 4 Sones is approximately the loudness of a normal television set when on.

Clearly, this would be ridiculously loud for a new bathroom fan, so you would need to be looking for a fan that is as low as possible, with 1.5 Sones considered to be relatively good.

In actual fact, there are some new fans available, especially from Panasonic and Broan that have very low Sone ratings, as little as 0.3 or 0.4 which to give you an idea is only a little louder than someone's quiet breathing.

Energy Efficiency

Energy Star

Energy efficiency is always a hot topic these days. And when it comes to the selection of the right fan for your bathroom this is no different.

Fortunately, manufacturer's have cottoned on to the need to make their devices as efficient as possible and many have adopted the government's Energy Star rating system.

This Energy Star rating provides a measure of flow or CFM per watt of energy. As most modern fans operate from 15 to 40 W which should give a CFM/W rating of between 10 and 20 to be perfectly achievable.

Other Features

Bathroom fans have been keeping up with the times. Now you can get a number of other features integrated into your fan unit, many of worth are well worth the consideration

Motion Sensor

Traditionally, bathroom vent fans were operated by a ceiling or wall switch. Many a time they were left on, sometimes for hours at a time. This problem was partially solved with the introduction of off-timers which would turn the fan off after a set period. But the technology has improved once again and now some units have motion sensors that detect motion in the room and automatically turn the fan on.

Humidity Sensors

In a similar way to the motion sensors mentioned above, some units incorporate humidity sensors which switch the fan on when the humidity level in the room reaches a certain threshold. This is perhaps the best option of all, as the purpose of installing most bathroom fans is to lower the room humidity to make it more comfortable to be in and to lower the risk of mold forming on surfaces due to the warm, moist conditions.


Many fan models incorporate a light. In smaller bathrooms this can make sense as a fan and a separate light can make a ceiling look cluttered and unsightly.


In the same vein as the light, there is often little opportunity to install a bathroom heater in many smaller bathrooms, so having one integrated into the fan unit can be a practical solution to an otherwise difficult problem. The heaters are typically of [the infrared heater[link]] variety as this provides [efficient and instant heat[link]].

Night light

Some models also have a night light programmed to come on when light levels drop below a certain threshold. These are low wattage lights which help you or your family to navigate the bathroom in the dark.

Installation Tips

Installation of bath fans is not as easy as many of us would like.

Many of the problems relate to venting rather than the installation of the fan itself. If mistakes are made, you may get a build up of water in difficult to reach places. This can lead to mould growth and water damage.

So rather than go through a detailed installation guide, which would be difficult as every situation will differ, we thought we'd provide a list of some of the issues that you might face and how to overcome them.

  • Always try to position your exhaust fan as close as possible to the bathroom fitting which is creating the most humidity and moisture. However, if you do install your extractor fan over or a shower unit then you should ensure that the electrical circuit is protected with a suitable ground fault circuit interrupter (GFCI).
  • Make sure that you insulate your ductwork. The reason for this is that as the warm moist air enters the ducting it can cool rapidly and form drips which run back the fan unit, and consequently into your bathroom.
  • If there is a long distance between the fan and the external vent, consider using ducts with a larger diameter. This allows the air to flow more freely, creating less drag. Allowing you to remove as much of the humidity as possible.
  • As previously stated always vent your bathroom exhaust fan to the outside. This ensures that the moisture is removed harmlessly from your home.
  • If you install a roof vent then make sure that the vent is sealed properly using flashing and appropriate waterproofing.
  • Don't assume that getting a more powerful fan is better. The danger is that the fan will be so powerful it will draw heat from the rest of the house and push it outside.
  • As previously noted make sure that there is a gap below the bathroom door to allow fresh air to enter the room. This is a specific recommendation of the Home Ventilating Institute. If you do not allow fresh air to enter the room efficiency of the fan is diminished, not to mention the fact that it may become unpleasant to remain in the room.

For more detail on ground fault circuit interrupters see here.


Bathroom exhaust fans are often an essential bathroom fitting. Allowing humid or moist air to remain in the room will make it uncomfortable for you to use and perhaps more importantly encourage condensation which can damage wood and paintwork and create the conditions for mould growth.

Extractor fans are a simple and affordable way in which to deal with the issue and with modern smart technology they are extremely energy efficient and best of all quiet in operation.

We hope you got some value from this article and would encourage you to return to the table of best bathroom extractor fans above and read the bathroom fan reviews to help you to purchase the right fan for you.