How to choose an exhaust fan

how to choose the right exhaust fan

An exhaust fan is a necessary addition to any bathroom/laundry or kitchen and the principle is a simple one. An extraction fan is designed to remove air from the room, commonly known as the process of ventilating. Every time you have a shower or bath steam and moisture is generated from the warm water, which will typically end up fogging up the bathroom mirrors and producing condensation on the bathroom tiles. If this moist air is not extracted from the bathroom it may end up contributing to problems such as damp and mould which over time can cause bigger problems.

A good quality Exhaust Fan will extract this air before it has a chance to turn into condensation. This means a good extraction fan will keep your bathroom mould and dampness free as long as it is turned on every time you have a bath or shower. Australian building codes state that an exhaust fan is mandatory. In this article we will take a look at how you can pick the right exhaust fan based on your needs.

What size exhaust fan do I need?

Determining which exhaust fan you need to buy is actually relatively simple for domestic installation. The most important factor is to pick a fan that has a capacity big enough based on your room size. All of our bathroom exhaust fans have a unit of measurement m3/hr. This is cubic meters per hour and the higher this number the more powerful the fan will be. The larger the room then the larger the fan you will need.

Step by step how to choose an exhaust fan

  • Measure the size of your room in meters (you will need length, width and height).
  • Take your measurements and multiply them (l x w x h)
  • For example a 2m long by 3m wide by 2.5m high room would be 2 x 3 x 2.5 = 15m3
  • For a bathroom with a shower we generally recommend achieving 15 air changes per hour, a toilet 10
  • So in our example 15 x 15 = 225 m3/hr
  • This means we know we should be looking for a fan that has a capacity of 225 m3/hr.

15 air changes per hour is our general base recommendation, a higher extraction rate can be calculated if you want a higher extraction rate. For the purpose of the above example we have based the calculation on a standard bathroom with a shower.

Other important things to think about when buying an exhaust fan

What type of fan? - The most popular installation location in Australia is in the ceiling. It is also possible to purchase units for wall and window installation depending on what you are after.

Exhaust Fan with Light - Do you need a fan with a built in light? There are many great models on the market including units with built in low wattage LED globes. Maybe you are replacing the old light fixture in the bathroom and you want to combine it with one that extracts and produces enough light for the bathroom.

Exhaust Fan with Heat Lamps - Looking for something with built in heat lamps? We have a huge selection, the heat lamps usually provide instant warmth, a great addition especially for those cold winter mornings.

Where to install the exhaust fan? - You may not have much choice if you are replacing an old fan - however if its a new fan in a brand new bathroom ideally you will have the fan opposite the source of inward air. This is generally opposite the door, which typically has a small gap below it to allow for fresh air to enter the bathroom. This cross flow of fresh air entering and air being extracted is whats going to ensure your fan services the entire room.

Will you Duct the fan? - If you want to duct your fan to the outside it is essential that you purchase a unit that is ductable. This will be indicated on each of our exhaust fan listings individually. We sell a comprehensive range of exhaust fan accessories.

Energy Efficiency - All exhaust fans are not created equal. Each one will have a motor power in watts. The higher the wattage the more powerful the motor but also the more expensive the fan will be to run.

Looking for a quiet fan? - As with the above each fan will generally have a decibel rating published. The lower the decibel rating the quieter the fan will be. Generally the more powerful the fan the more of a component of noise.

Can I install the fan? - Some exhaust fans are designed to be DIY installation. This will mean the fan comes with a lead and plug so it connects to a powerpoint meaning all you have to do is plug it in. other models will require hardwiring which will need to be done by a qualified electrician.

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Published on 19th April 2016