The fastest way to tell: look above and behind your range hood for metal ductwork running to the outside of your house. If it's there, you have a ducted hood, which exhausts smoke, grease and moisture outdoors. If there's no ductwork at all, you have a ductless (recirculating) hood, which filters the air and blows it back into the kitchen through a charcoal filter. Knowing which one you have changes both how you maintain it and what to expect from it.
This piece supports two others in the kitchen cleaning cluster on House Tweaks: cleaning the filter and diagnosing why a hood isn't pulling smoke out, both of which depend on knowing this first.
Why this matters for cleaning and troubleshooting
A ducted hood's job is to physically remove smoke, grease particles and moisture from the kitchen, and its performance depends on a clear duct path in addition to a clean filter. A ductless hood was never designed to remove anything from the room; it filters and recirculates, which means it will always feel less powerful than a ducted hood, and no amount of cleaning changes that basic design. If you're troubleshooting weak performance, knowing which type you have tells you whether you're chasing a real problem or expecting something the hood was never built to do.
How to check in two minutes
- Open the cabinet above your range hood, or look behind it if it's a wall-mounted unit, and look for round or rectangular metal ductwork.
- If you can trace that ductwork to an exterior wall or roof vent, you have a ducted hood.
- If there's no ductwork at all connecting the hood to the outside, and the unit simply pulls air through a filter and releases it back into the kitchen, you have a ductless/recirculating hood.
- Still unsure? Check the underside or top of the hood for a visible charcoal filter cartridge, in addition to the metal grease filter. A charcoal filter present alongside the metal one is a strong sign of a ductless setup, since ducted hoods don't need one.
What a ducted hood means for you
Expect stronger smoke and odor clearing, since the air is actually leaving the kitchen. Maintenance means keeping the metal filter clean (see cleaning a greasy range hood filter) and occasionally checking that the exterior vent damper opens and closes freely. If performance drops off, the duct path itself, not just the filter, becomes a suspect; why a range hood stops pulling smoke out covers that in order.
What a ductless or recirculating hood means for you
Expect less dramatic smoke clearing even when everything is working exactly as designed, since the air never leaves the room. Maintenance is two-part: the metal or baffle filter still gets cleaned regularly, and the charcoal filter gets replaced on a schedule (typically every three to four months) rather than washed, since charcoal can't be "recharged" by rinsing.
Microwave-hood combos and downdraft units
Two setups confuse this check further. An over-the-range microwave with a built-in vent fan can be wired either way, ducted to the outside or recirculating through a charcoal filter, and the only reliable way to tell is the same ductwork check described above, done around the microwave rather than a standalone hood. Downdraft vents, which rise up from behind or beside the cooktop rather than hanging above it, are almost always ducted, typically running down through the cabinetry and out through the floor or an exterior wall, and follow the same ducted-hood maintenance rules.
If you're not sure or can't tell
Some kitchens have unusual layouts, boxed-in ductwork, or a hood installed by a previous owner with no documentation. If you genuinely can't determine the type from a visual check, a qualified appliance installer or kitchen contractor can confirm it, and any change to venting (adding ductwork where there is none, for example) is worth checking against local building code first, since requirements vary by area and this isn't something to assume is universal.
FAQ
How can I tell if my range hood is ducted or ductless?
Look above or behind the hood for metal ductwork leading to an exterior wall or roof vent. If it's there, the hood is ducted. If there's none, and the unit has a charcoal filter in addition to the metal grease filter, it's ductless/recirculating.
Is a ducted range hood better than a ductless one?
For actually removing smoke, grease and moisture from the kitchen, a ducted hood performs better, because the air leaves the room entirely. A ductless hood filters and recirculates, which is a real limitation of the design, not a sign something is broken.
Can I convert a ductless range hood to ducted?
That typically means adding ductwork and an exterior vent, which is a job for a qualified installer, and may be subject to local building code depending on where you live. It isn't a simple filter swap.
Do ductless range hoods need a special filter?
Yes. In addition to the washable metal or baffle filter, ductless hoods use a charcoal (carbon) filter to absorb odors before recirculating the air. That charcoal filter is replaced on a schedule, not cleaned.
Does an over-the-range microwave count as a range hood?
If it has a built-in vent fan, it functions as one, and it can be wired either as ducted or recirculating just like a standalone hood. Check for ductwork above or behind it the same way you would a regular hood to find out which type yours is.
Are ductless range hoods worth having at all if they don't vent outside?
They still capture grease particles through the mesh filter and reduce some odor through the charcoal filter, so they're better than nothing, particularly in kitchens where adding real ductwork isn't practical. They're just a different, less complete solution than a ducted hood, not a broken or lesser version of one.
Does the type of range hood I have affect how often I need to clean it?
It affects what you're cleaning more than how often. A ducted hood mainly needs its metal filter kept clean and its exterior duct path unobstructed. A ductless hood needs the same metal filter cleaning plus a charcoal filter replaced on schedule, which is effectively an extra maintenance task the ducted setup doesn't have.
Why would a builder install a ductless hood instead of a ducted one?
Running ductwork to the outside isn't always possible or affordable depending on where the range sits in the house, particularly on an interior wall or a kitchen island far from any exterior wall. A ductless hood sidesteps that construction cost entirely, which is the main reason it gets chosen over a ducted setup in those layouts.
Does this check work the same way in an apartment or rental kitchen?
Yes, the identification method itself doesn't change based on ownership. What can differ in a rental is whether you have permission to alter venting at all, which is a separate question from simply identifying what's already installed and maintaining it as-is.
