How to Choose a Range Hood: CFM, Mount Type, and Ducting That Actually Clear the Air

A range hood is the quiet workhorse of a kitchen -- it pulls grease, steam, smoke, and cooking smells out before they settle on your cabinets and drift through the house. It is also a major visual element hanging right at eye level over the cooktop, so it has to look right and work hard at the same time. Most people undersize it, vent it wrong, or pick a model that is far too loud to ever run. Choosing well comes down to how it vents, how much air it moves, how it mounts, and how it sounds. Here is how to choose a range hood that actually clears the air.

Ducted vs Ductless

The first and biggest decision is whether the hood vents outside. A ducted (vented) hood pushes air through a duct to the exterior, removing heat, moisture, grease, and odor for good -- this is by far the better performer and the right choice whenever a duct run is possible. A ductless (recirculating) hood instead pulls air through a charcoal filter and blows it back into the room; it captures some grease and odor but does nothing about heat or humidity, and the filters need regular replacing. Ductless is a fallback for apartments and interior walls where venting outside simply is not feasible -- not a first choice. If you can run a duct, do; if you cannot, set expectations accordingly and stay on top of the filters.

Size the CFM to Your Cooktop

A hood's power is measured in CFM -- cubic feet of air per minute. Too little and smoke escapes the hood; too much and you are needlessly loud and pulling conditioned air out of the house. The practical rule for a standard electric or gas range is roughly 100 CFM per linear foot of cooktop, so a 30-inch range wants about 250-300 CFM as a baseline. Gas burners need more because they throw more heat: a common guideline is to total your burner BTUs and provide about 1 CFM per 100 BTU. Heavy cooks, high-output gas, or a griddle push you higher; a light-use kitchen can stay at the baseline. Also factor the duct: a long run with elbows chokes airflow, so a higher-CFM blower helps if the path to the exterior is not short and straight.

Match the Mount Type to Your Layout

The hood's format is dictated by where the cooktop sits. An under-cabinet hood tucks beneath the upper cabinets over a wall range -- compact and budget-friendly. A wall-chimney hood mounts on the wall with no cabinet above and makes a bold stainless or designer statement over the range. An island (ceiling-mount) hood hangs from the ceiling over a cooktop in an island and needs more CFM, since it has open air on all four sides. An insert/liner (also called a power pack) is a bare blower unit you build into a custom wood or plaster hood surround for a fully integrated look. There are also downdraft vents that rise behind the cooktop -- a last resort for islands where an overhead hood is impossible, since pulling smoke downward fights physics. The over-the-range microwave combo saves space but vents weakly; skip it if you cook seriously. Pick the mount that fits your layout first, then choose within it.

Width, Capture Area, and Mounting Height

The hood should be at least as wide as the cooktop -- and ideally a few inches wider on each side, so an island hood especially benefits from sizing up to 36 inches over a 30-inch range to catch the plume. Mounting height matters just as much: too high and smoke escapes before it is captured, too low and you bump your head and risk heat damage. Follow the maker's spec, but a typical range is 24-30 inches above an electric cooktop and 27-36 inches above gas. A deeper hood with a larger capture area and a perimeter or baffle design grabs more of the rising smoke than a shallow flat one. This is the element people forget: a powerful blower in a hood mounted too high or too narrow still lets smoke slip past the edges.

Noise, Lighting, and Filters

The best hood is the one you will actually turn on, and noise is what stops people. Loudness is rated in sones -- lower is quieter -- and a hood that is bearable at its lower speeds gets used, while a screamer gets left off while grease builds up. Look for multiple fan speeds so you are not stuck running full blast for a simmer. Check the lighting too: bright, well-placed LEDs over the cooktop make a real difference in how you cook, and they are on far more than the fan. For filters, baffle filters (stainless, dishwasher-safe) outlast and outperform the old mesh filters, and a recirculating hood adds a charcoal filter you will replace periodically. Quiet, well-lit, and easy to clean is what keeps a hood in daily service.

Common Range-Hood Mistakes

• Undersizing the CFM. Too little airflow lets smoke and grease escape; size to your cooktop width and gas BTUs.
• Choosing ductless when you could vent. Recirculating leaves heat and humidity behind -- duct to the exterior whenever the run is possible.
• A hood narrower than the cooktop. The edges of the plume slip past; match or exceed the cooktop width, especially over an island.
• Mounting it too high. Smoke disperses before capture -- follow the height spec for electric vs gas.
• Ignoring the sone rating. A hood too loud to run is a hood that never clears the air; check noise at the speeds you will actually use.
• Relying on an over-the-range microwave. Its weak fan is no substitute for a real hood if you cook with heat and grease.

See It Over Your Cooktop First

A range hood is a big visual commitment over the busiest part of the kitchen, and it is hard to picture a bold wall-chimney or a tucked-away insert before it is in. Upload a photo and preview hood styles, finishes, and proportions over your actual cooktop with Room Reveal before you buy. For the surrounding look, browse modern kitchen ideas and industrial kitchen ideas, and coordinate the rest of the kitchen with our guides to choosing a kitchen backsplash and decorating a kitchen.