Every kitchen throws contaminants into the air while you cook — smoke from searing proteins, steam from boiling pots, grease particles lifted by frying, and volatile organic compounds released when oils heat up. Leave them alone and they settle on walls, ceilings, cabinets, and upholstery, making your kitchen harder to live in and speeding up wear and tear. An oven extractor fan — also called a range hood or kitchen ventilation hood — is the most effective single appliance for capturing these contaminants where they're created. This guide walks you through the different types available, how to size one properly, and what it takes to keep one running for years.
Why Kitchen Ventilation Matters
The case for good ventilation goes well beyond banishing cooking smells. Indoor air quality while you cook can actually be worse than outdoor air in heavily polluted cities. A 2019 study in the journal Environmental Science & Technology found that frying and sautéing without proper ventilation can produce particulate matter concentrations 10 to 30 times higher than outdoor urban levels. Those fine particles reach deep into the lungs, aggravating respiratory conditions and contributing to long-term cardiovascular risk.
Health is only part of the story. Poor ventilation accelerates kitchen wear: grease settles on cabinet fronts, countertops, light fixtures, and walls, turning sticky and discolored over time, and that residue becomes genuinely hard to remove. The buildup is also a fire hazard, especially near cooktops and ovens. A correctly sized, properly installed extractor fan captures grease at the source before it ever lands on your surfaces.
There's also the moisture angle. Boiling water, steaming vegetables, and simmering sauces release a steady volume of water vapor that condenses on cool surfaces and invites mold and mildew. In kitchens with weak ventilation, condensation on windows, walls, and ceilings leads to peeling paint, bubbling wallpaper, and discolored grout. A fan with enough airflow removes that moisture before it can condense and do damage.
The Different Types of Extractor Fans
Extractor fans differ along two lines: how they're installed and how they vent the air. Understanding both makes it easier to pick a fan that fits your kitchen's layout and its performance needs.
By Installation Style
Under-Cabinet Hoods
The default choice for most homes, under-cabinet hoods mount directly below an upper cabinet, right above the cooktop. Their slim profile slips into existing cabinetry, and both the capture area and ductwork fit inside a compact footprint. Typical widths run from 24 to 36 inches, matching standard cooktop sizes. They're also the easiest to install in an existing kitchen, since they ask for very little modification to cabinetry or walls.
Wall-Mounted Chimney Hoods
Chimney hoods attach to a wall and rise upward through a decorative — or purely functional — flue that hides the ductwork. These are statement pieces, often becoming the visual anchor of the whole kitchen. They provide a larger capture area than under-cabinet units and come in a broader range of looks, from clean stainless steel to warm wood finishes. Because they need open wall space above the cooktop, they suit open-concept kitchens and layouts where the cooktop sits against a bare wall.
Island Hoods
Island hoods hang from the ceiling above a cooktop set away from any wall — typically a kitchen island. They have to support their own weight and run ductwork up through the ceiling to an exterior vent. Because they can't lean on surrounding walls to corral rising air, island hoods tend to be bigger and stronger than wall-mounted units, capturing air from every direction. They carry a premium price and generally need professional installation for the structural support and ceiling ducting.
Downdraft Ventilation
Downdraft systems flip the approach: instead of pulling air up into a hood, they draw it downward through vents built into the cooktop surface. They're a good fit for kitchen islands where an overhead hood would block sightlines or fight the design. Downdraft models have improved over the years, but they still capture air less efficiently than overhead hoods, because they're working against the natural tendency of heat and steam to rise. They handle low-heat cooking well and fall short during high-heat searing or wok cooking.
By Ventilation Method
Ducted (External Venting)
Ducted extractor fans push contaminated air through ductwork and out of the house. This is the gold standard for kitchen ventilation, because it completely removes heat, moisture, smoke, grease particles, and odors from your living space. Ducted systems outperform recirculating models by a wide margin, and many building codes require them in new construction. Keep the duct run as short and straight as possible, with minimal bends, to maximize airflow and minimize noise. Rigid metal duct beats flexible duct here: its smooth interior reduces friction and keeps grease from collecting in the corrugations.
Recirculating (Ductless)
Recirculating extractor fans pull air through a multi-stage filter setup and send the cleaned air back into the kitchen. The filtration usually starts with a metal grease filter that catches airborne oil, followed by a charcoal (activated carbon) filter that absorbs odors and volatile organic compounds. For many apartment dwellers and homeowners who can't add external ductwork, recirculating systems are the only realistic option. They do a decent job on odors and airborne grease, but they don't remove heat or moisture — a real drawback during long cooking sessions in warm climates.
Sizing Your Extractor Fan Correctly
Sizing is where fans succeed or fail. Too small and the fan can't capture contaminants before they drift away; too large and you waste energy and put up with unnecessary noise. The key spec is CFM (cubic feet per minute) — the volume of air the fan moves each minute.
- Minimum standard: 1 CFM per square foot of kitchen area. A 100-square-foot kitchen needs at least 100 CFM.
- Gas cooktop adjustment: Add 100 CFM for every 10,000 BTU of burner output. A 50,000 BTU gas range calls for at least 500 CFM.
- Island cooktop adjustment: Bump the CFM requirement up by 50% for island installations, since the hood has to capture air from every direction.
- Ductwork adjustment: Every 90-degree bend cuts effective airflow by roughly 10%; every 45-degree bend by about 5%. Factor those losses in when you calculate.
Top Models, Side by Side
| Model | Type | CFM | Noise Level | Key Feature | Price Range |
|---|---|---|---|---|---|
| Bosch 800 Series | Under-cabinet | 400 | 1.5 sones | Extremely quiet operation | $400 – $600 |
| Broan Elite 600 Series | Wall-mounted chimney | 600 | 3.0 sones | High CFM; LED lighting | $500 – $800 |
| WhisperKOOL SC 6000i | Island | 900 | 4.5 sones | Sleek design; powerful extraction | $1,200 – $2,000 |
| KitchenAid KXW7536YPS | Under-cabinet | 450 | 2.0 sones | Perimeter venting; dishwasher-safe filters | $500 – $700 |
| Fisher & Paykel CV302G2 | Wall-mounted | 650 | 2.5 sones | Heat sensor auto-activation | $800 – $1,200 |
Installation Considerations
Installation runs the gamut from a straightforward under-cabinet swap to a complex island hood project. The things that matter most:
- Height above cooktop: Gas cooktops need 24 to 30 inches of clearance between burner and hood; electric cooktops can sit as close as 18 to 24 inches. Check your local building codes for exact figures.
- Duct size: Match the duct diameter to the fan's outlet size. Most residential fans use 6-inch or 7-inch round duct. Going smaller than the fan's output creates backpressure that cuts performance and raises noise.
- Makeup air: In tight, well-sealed homes, powerful fans (typically 400+ CFM) can create negative pressure that pulls combustion gases back down water heater and furnace flues. Many building codes therefore require a makeup air system — a damper that opens automatically to bring in fresh air when the fan runs at high speed.
- Electrical requirements: Most extractor fans need a dedicated 120-volt, 20-amp circuit; high-CFM models may call for 240-volt service. Sort out electrical routing before you commit to a hood.
- Noise levels: Noise is measured in sones (1 sone ≈ the sound of a quiet refrigerator a meter away). Fan noise varies widely between models and speed settings: a 1-sone fan is nearly silent, while a 4-sone fan is clearly audible. For open-concept kitchens, favor low-sone models so conversation stays easy.
Maintenance for Longevity
Regular upkeep keeps your extractor fan performing at its best and lowers fire risk:
- Clean metal grease filters monthly: Soak them in hot, soapy water for 15 minutes, scrub gently with a non-abrasive brush, rinse, and dry completely before reinstalling. Many dishwasher-safe filters can go on the top rack of your dishwasher.
- Replace charcoal filters every 3-6 months: Recirculating systems depend on activated carbon to absorb odors, and once the carbon saturates, the filter stops working. Put a recurring reminder on your calendar.
- Wipe the exterior weekly: A grease film builds up on the hood's outer surface. A damp cloth and mild detergent keeps it from hardening into a tougher cleanup job.
- Inspect ductwork annually: For ducted systems, check for grease accumulation, disconnected joints, or pest damage. Professional duct cleaning every 2-3 years removes grease that could otherwise become a fire hazard.
- Test the fan regularly: Run the fan at every speed setting once a month to confirm the motor runs smoothly and nothing obstructs the blades. Unusual sounds or vibration are signs to investigate promptly.
Related Guides
Round out your kitchen with our Built-In Ovens and Microwaves Guide and Kochfelder Cookware Guide. Need coffee to go with all that cooking? See our Krups Coffee Machines Guide.
Frequently Asked Questions
What's the difference between ducted and recirculating extractor fans?
Ducted extractor fans push air outside through a duct pipe, removing heat, moisture, smoke, and odors completely. Recirculating fans pass the air through charcoal filters and send it back into the kitchen. Ducted systems are more effective but need external venting; recirculating units are easier to install in apartments or homes without exterior wall access.
How often should I replace the charcoal filter in my extractor fan?
Every 3 to 6 months, depending on how much you cook. Heavy cooking — daily frying or high-heat work — means more frequent replacement. Metal grease filters, by contrast, get cleaned monthly and don't need replacing.
What CFM rating do I need for my kitchen extractor fan?
A good rule of thumb is 1 CFM per square foot of kitchen area — so a 100-square-foot kitchen wants about 100 CFM. If your cooktop is gas, add 100 CFM for every 10,000 BTU of burner output. A kitchen with a 50,000 BTU gas range, for example, needs at least 500 CFM.
Can I install an extractor fan without external venting?
Yes. Recirculating (ductless) extractor fans use charcoal filters to clean the air before returning it to the kitchen. They're less effective at removing heat and moisture than ducted systems, but they're ideal for apartments and homes where external venting isn't possible or permitted.
