Instructions

• 1). Determine if you need a room fan or a whole-house fan, then review the fan's cubic feet per minute (CFM). For instance, manufacturers rate exhaust fans according to their ability to move air, and that rating is based on how many cubic feet of air a fan can move per minute. For single-room fans that operate in a bathroom or kitchen and move less air than one that aerates an entire home, look for a 200 to 700 CFM, depending on the size of the room. Whole-house fans should rate 500 to 1500 depending on the size of your home. Bathroom fans should rate at 100 to 500 depending on the size of the bathroom and the amount of condensation the fan must aerate.
  
  
• 2). Compare noise levels according to sone level, which means the perceived noise level of an object. Manufacturers rate exhaust levels from 1 to 4 sones. A quiet bathroom fan rates ½ sone. A noisy fan will rate 2 or higher. Also, look for exhaust fans with firm housing and construction, which will reduce noise at high speeds.
  
  
• 3). Compare prices. The average price for whole-house exhaust fans ranges from $150 to $350. Single-room exhaust fans range from $35 to $100. Price range also depends on the noise level of the fan. Quiet fans typically cost more than noisy fans, so try not to sacrifice quiet just to save a few bucks.
  
  
• 4). Shop for features. For instance, some fans come with automatic switches or multiple speed settings. An automatic switch operates in conjunction with a timer or a thermostat and switches on when the air temperature reaches a certain level. Multiple speed settings help cool a room or house at various speeds depending on the particular need.