Ducted vs Recirculating Rangehoods: Which One Actually Clears Smoke and Oil?

If your kitchen still smells like last night's stir-fry the next morning, or there's a faint film of oil on your splashback after cooking, the problem usually isn't your cooking — it's your rangehood. And the single biggest factor in whether a rangehood actually clears smoke and oil, rather than just moving it around, is whether it's ducted or recirculating.

Both types sit above your cooktop and both pull air in. What happens to that air next is where they're completely different — and it's the difference that matters most if you cook at high heat, cook with a wok, or simply want a kitchen that doesn't hold onto smoke and grease.

Here's how each one actually works, which one clears smoke and oil more effectively, and when recirculating is genuinely your only option.

How Ducted and Recirculating Rangehoods Actually Work

Ducted (Extraction) Rangehoods

A ducted rangehood pulls smoke, steam, and airborne oil particles in through the filter, then pushes that air out of your home entirely — through ducting that runs to an external wall, roof cavity, or vent. Nothing recirculates back into the kitchen. Whatever your cooktop produces, a properly sized ducted rangehood removes it from the building.

This is why ducted systems are the standard recommendation for high-heat and wok-style cooking, where the volume of smoke, steam and oil vapour is significantly higher than everyday cooking. You can browse Robam's full range of Ducted Rangehoods, including 90cm, 75cm and 60cm options.

Recirculating (Filtered) Rangehoods

A recirculating rangehood pulls the same air in, but instead of venting it outside, it passes the air through a filter — typically a carbon or charcoal filter — to strip out odour and grease, then releases the filtered air back into the kitchen. Nothing leaves the building; the air is cleaned and recycled.

Recirculating rangehoods exist because not every kitchen can be ducted to the outside (more on that below), and Robam's Recirculating Rangehoods — available in 90cm, 75cm and 60cm — are built to get as close as possible to ducted-level performance within that constraint.

Which One Actually Clears Smoke and Oil Better?

Ducted, and it's not particularly close. Because a ducted system removes air from the home instead of filtering and reusing it, it doesn't rely on a filter's ongoing effectiveness to keep your kitchen clear. Oil vapour, in particular, is difficult to filter out completely — even a good carbon filter will let some through, and its performance drops as it loads up with grease over weeks of cooking. A ducted rangehood simply sends that oil vapour outside before it has the chance to settle on your cabinetry, splashback, or in your kitchen's soft furnishings.

Recirculating systems can still meaningfully reduce smoke and odour, especially for everyday cooking, but they're working with a harder constraint: the same air keeps cycling through the kitchen until the filter catches enough of it. On a big cooking session — a pot of stock, a batch of dumplings, a proper stir-fry — that's a lot of air for a filter to keep up with.

Why This Matters More for High-Heat and Wok-Style Cooking

This gap between ducted and recirculating widens considerably once you're cooking at wok temperatures. High-heat, high-smoke cooking — the kind that gives food real wok hei — produces far more airborne oil and smoke in a short burst than gentle simmering or baking ever will. That's exactly the scenario a rangehood needs to be built for, and it's why Robam pairs its ducted rangehoods (rated up to 2400+ m³/hr extraction) with the high-output burners in the Cooktops range — the two are engineered to work as a system, not sold as separate afterthoughts.

If a recirculating rangehood is your only option and you cook this way often, it's worth reading up on extraction rate and rangehood sizing more broadly, and being realistic that a recirculating system will need more attention (see the maintenance note below) to keep performing.

When Recirculating Is the Only Option (and How to Make It Work)

There are genuine situations where ducting to the outside simply isn't possible, and a recirculating rangehood isn't a compromise so much as the only workable choice:

• Apartments and strata properties, where you can't cut through an external wall, run ducting through a shared roof cavity, or make structural changes without body corporate approval.

• Rentals, where landlords won't permit ducting modifications.

• Kitchens in the middle of a floor plan, with no nearby external wall, window, or roof access to vent to.

• Heritage or strata-heritage buildings, where facade and structural changes are restricted.

If any of these apply to you, a recirculating rangehood is the right call — but a few things make a real difference to how well it performs:

1. Don't undersize it. Choose the highest extraction rate (m³/hr) recirculating model that suits your kitchen and cooktop, not the cheapest option. The filtering process is already less efficient than ducting outside, so starting with strong airflow matters more, not less.

2. Replace filters on schedule. A carbon filter that's overdue for replacement is doing a fraction of its job. Robam's Rangehood Filters are designed to match your model, and swapping them on schedule is the single biggest thing you can do to keep a recirculating system clearing smoke and oil effectively.

3. Match your cooking style to your expectations. If you cook at high heat often, a recirculating rangehood will still help, but it won't match a ducted system's performance. Extra ventilation — an open window, a kitchen exhaust fan if you have one — can help bridge the gap on big cooking days.

Ducted vs Recirculating at a Glance

How to Choose the Right One for Your Kitchen

Before you decide, it's worth answering three questions honestly:

• Can you actually duct to the outside? If you own the property, aren't in a strata building, and have access to an external wall or roof cavity, ducted is almost always the better-performing choice — and it's worth checking with your builder or kitchen designer at the renovation-planning stage, since retrofitting ducting later is far more disruptive than planning for it upfront.

• How often — and how intensely — do you cook? Occasional cooking with moderate heat can be handled reasonably well by a good recirculating system. Frequent high-heat or wok-style cooking is where the gap to ducted performance becomes obvious.

• What are you willing to maintain? Ducted rangehoods still need regular filter cleaning, but recirculating systems ask more of you — the carbon filter is doing more of the work, so it needs closer attention.

There's no wrong answer if you choose based on what your kitchen and building actually allow — the important part is choosing a model sized and rated for how you really cook, not just what fits the space.

Explore Robam Ducted and Recirculating Rangehoods

Whichever venting type suits your kitchen, the full Rangehoods range includes integrated, undermount, canopy and side suction styles in both ducted and recirculating options, so you don't have to trade off extraction power for the look or install type you want. Browse Ducted Rangehoods or Recirculating Rangehoods to find the right fit for your kitchen.