Shopping for kitchen ventilation systems may not be as exciting as considering new cooktops, but it's just as important. Surface cooking releases heat, steam, grease, and odors that you don't want floating around your kitchen.
Your choices in ventilation are updraft and downdraft systems, and ducted and ductless systems.
An updraft system consists of a range hood that hangs over the cooktop and sucks up steam and odors, venting them outside or recirculating them. Microwave/hood combinations have become popular because they save space, but they aren't recommended for professional-style ranges. Updraft systems are more efficient because hot air rises naturally, but they aren't always convenient.
A downdraft system pulls air down through vents built flush with the cooktop or, more commonly, built into the back of it. If your cooktop is on an island, a downdraft system may be more desirable.
If you have a duct system, above all, be sure the ventilator is ducted outside. Ductless (or recirculating) range hoods filter soot and some odors emitted from cooktops, but most pollutants are recirculated right back into the room. Ductless hoods aren't recommended with gas ranges.
Ducted range hoods use fans or blowers. Propeller-style fans twist air up the exhaust duct, causing the air to drag against its sides and reducing the exhaust output. More efficient blowers suck air without causing as much turbulence, reducing air drag inside the duct.
To choose a hood, measure the cooking surface to make sure the hood will cover all the burners. At the store, watch hoods in action. Look for a design that pulls rising cooking vapors and contains them until the blower can carry them outside.