A whole house ventilation system is required because natural ventilation doesn’t provide adequate air quality inside the house.

A Whole house ventilation systems provide controlled and uniform ventilation throughout a house. Whole house systems use one or more fans and duct systems to exhaust used air out of the house and supply fresh air into the house.

There are typically 4 types of Whole House Ventilation Systems:

• Exhaust ventilation systems: These systems force air out of a home.
  
• Supply ventilation systems: These systems force air into the home.
  
• Balanced ventilation systems: These systems force equal amounts quantities of air in and out of the home so that there is proper balance of air in the house.
  
• Energy recovery ventilation systems: These systems transfer heat from incoming or outgoing air to minimize energy loss.

People opt for whole house fan ventilation system to save money on cooling equipment and operational cost on electric bills. The cost for a whole house fan is $150–$350 as compared to the cost for central air conditioning, which runs $2,000–$4,000. Also whole house fans use one-quarter the power of central air conditioning.

Whole house fans cool the entire house using air from outside instead of “conditioning” inside air like the air conditioner. A whole house ventilation system replaces used air inside the house with fresh air and keeps air moving through a home and this moving air feels cooler than still air.

Most home heating and cooling systems are not designed to circulate fresh air into the home. A whole house fan solves this problem.

According to the U.S. Department of Energy, whole house fans are a simple and inexpensive method of cooling a house. They provide excellent ventilation (by changing the air inside the house and venting odors quickly), lower indoor temperatures, and improve evaporative cooling.

S E L E C T I N G the Best Whole H O U S E F A N

FAN SPEED: A two-speed fan permits the entire house to be ventilated quickly on high speed (such as when the occupants first arrive at home) and then provides gentle air circulation at the lower, quieter speed. A variable speed unit offers more flexibility in selecting the desired air movement.

CONTROL OPTIONS: Control may be a simple on/off pull or wall switch, a multi-speed rotary wall switch, or a timer that automatically shuts off the fan at pre-selected time intervals.

LOUVERS: Dampers or louvers typically operate automatically whenever the fan is on. Motorized dampers are available but are not necessary if the louvers are correctly installed and maintained.

MOTOR MOUNTS AND NOISE: A direct drive unit has its fan blades attached directly to the motor shaft. This type of unit is usually less expensive to buy and operates at a higher speed than it’s belt-driven counterpart. A belt-driven unit typically features a motor driving a slower moving, larger-diameter fan with four or more blades. It may be quieter, but will require maintenance of the pulley and belt.

H E L P F U L R E M I N D E R S

Label the attic-side box cover and the fan switch to remind users to remove energy saving covers. Instruct occupants to open at least two or more windows before operation, especially windows in occupied rooms where cooling is desired. It is important to ensure that all penetrations between the attic and living space are sealed and that the attic is properly ventilated. A central hallway, or a stairway in a two-story house, is the most common location.

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