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What is a CFM Rating?

CFM or Cubic Feet per Minute effectively helps measure the performance of an exhaust fan. By measuring the CFM of the room you want to install the fan in, you can be sure that you are choosing the correct size fan for the area.

Bathroom exhaust fans are a perfect example of using a CFM rating. An exhaust fan works to remove the air in the room and bring in new fresh air. In a bathroom where steam is involved, an exhaust fan works to remove moisture from the air which can cause mold and wood rot. Both are very expensive problems to fix. The correct size exhaust fan should be able to replace the air in the room 8 times per hour.

How to Choose the Correct Size Fan for your Room

There are many options when it comes to choosing the correct fan for your space. Panasonic Ventilation Fans  and Broan Ventilation fans offer many great selections of fans. Knowing how to calculate the CFM of your room is the key to having an effective fan.

Step 1: Measure your rooms dimensions: this includes the wall to wall measurements as well as the ceiling to floor measurement.

Step 2: Calculate the the floor area: do this by breaking your room into a series of rectangles or squares and multiplying the width x length then adding them together.

Step 3: Find the Volume of the room: use the floor area measurement and multiply it by the ceiling height

Step 4: Calculate the CFM: remember the fan needs to replace the air 8 times per hour. Divide the bathrooms volume by 7.5 to arrive at your CFM.

To find a bathroom fan to suit your needs, view our full selection of bathroom fans

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