How to Choose the Right Whole House Fan for Your Home's Size and Layout

by George Karonis

Installing a whole house fan can be an eco-friendly way to reduce your home temperature while saving on your utility bills.

How to choose a whole house fan based on your home’s size and layout?
To achieve the maximum cooling effect, choose a whole-house fan that is appropriate for your home, taking into account its size and layout.

To determine the right size whole house fan: 

Measure your house’s cubic footage: 

●       Determine the home’s square footage: Measure the length and width of each room in your house. Multiply the two numbers to get the square footage of each room. Add the square footage of all the rooms to determine the square footage of your house.

●       Measure the home’s cubic footage: Multiply the home’s square footage by the ceiling height to get the home’s cubic footage.

Calculate the required CFM:
The airflow capacity of your whole house fan, measured in cubic feet per minute (CFM), will depend on the square footage of your home and the number of air changes per hour (ACH) you need. Typically, whole house fans must have an ACH of 1500 to 7000 CFM.

Consider the climate in your area:
Get a whole house fan based on the climate in your area.

●       For coastal areas: Fans with 2 CFM/square foot;

●       For inland areas: Fans with 2.5 CFMs/square foot;

●       For desert areas: Fans with 3 CFMs/ square foot are recommended

Consider the home’s ceiling height:
A house with a ceiling height over 8 feet will require a larger whole house fan to ensure an increased air volume.

A single fan vs. a multi-fan system:
Whole house fans can be installed centrally or in a multi-zoned system. In a central system,  a single fan is installed at the midpoint of a single-storied home or the top of the stairs in a two-story home. Alternatively, whole house fans can be installed in multiple rooms as a multi-zoned system.

Consider appropriate attic venting: 

For proper attic ventilation:

●       Adequate attic exhaust: Ensure one square foot of free vent area for every 750 CFM.

●       Measure existing vents: Calculate the total free vent area.

●       Install additional vents: Where the attic lacks adequate ventilation, install additional vents.

Other factors:

●       Noise level preferences.

●       The ease of installation.

●       Convenience of operations, whether remote controls or wall-mounted controls.

To know more about getting a whole house fan according to your house size and layout, contact us at 1-661-775-5979.

Back to Whole House Fan Blog