Size of vent hood — For efficiency, the hood needs to be at least as wide as the range or cooktop. When selecting a range hood, measure your cooking surface before going shopping. Vent hoods are usually built-in and are wired directly to the household electrical system.
Your ductwork — Proper installation of ductwork is critical to the efficiency of the range hood. It’s important to include the installation of a duct in your budget—the steamy, greasy vented air needs to go somewhere, and the duct connects kitchen vent hoods to the exterior of your home. The farther away the vent hood is from an outside vent, the stronger the fan should be. Exhaust should always be vented outside, not to an interior wall or other enclosed space. Check with a contractor before purchasing an exhaust fan.
Cubic feet per minute (CFM) — The amount of air that the vent fan circulates will correspond to the effectiveness of removal of smoke and odors from your room. Air movement is measured in cubic feet per minute (CFM). Look for this rating on the units you are comparing. The higher the CFM, the more air is moved.
Noise level (SONES) — Remember to consider the amount of noise the fan will make. If you are entertaining guests while cooking, you want to be able to hear them over the fan noise. Select a range hood with variable fan speeds. A sone is a measurement of sound. A refrigerator and normal conversation both create roughly one to four sones. Use sone ratings to compare units, but be aware that the higher the CFM, the higher the sone rating is likely to be.
Lighting — Almost all range hoods are equipped with lighting, either with incandescent or halogen lights, placed above the cooktop to provide plenty of illumination when using your range. Some hoods are even equipped with heat lamps to keep your food warm.
