Ducted vs Ductless Chimney: Which One Actually Suits a Closed Kitchen

Last year a client called us with a problem. The cabinet edge right above her stove had started peeling after just two years. The reason turned out to be a cheap ductless chimney that was trapping steam and heat inside her closed kitchen, day after day. This is the one thing people forget when buying a chimney — it’s not just about clearing smoke. It affects the health of your whole kitchen.

We’ve installed and repaired both types of chimneys across Delhi NCR for years. So let’s break it down in plain terms — how each one works, and which one actually suits a closed kitchen.

How They Work

A ducted chimney pulls air through a mesh filter that catches oil, then pushes that air outside through a pipe in the wall or ceiling. Smoke, oil vapour, heat, and humidity — everything leaves the kitchen for good.

A ductless chimney passes air through two filters — mesh and charcoal — and sends the cleaned air right back into the kitchen. No outside pipe needed. But the heat and moisture stay in the room, which is something most people don’t think about.

Why This Matters for Indian Cooking

Daily tadka, pressure cooker steam, high-heat frying — every Indian kitchen deals with all three. Both types of chimneys handle smoke and smell reasonably well, if the charcoal filter is good. But only a ducted chimney actually removes the heat and humidity from the room.

In a closed kitchen, that trapped heat matters a lot. We’ve seen kitchens where a ductless chimney ran for years, and the cabinet edges near the stove started peeling — because the air stayed warm and damp long after cooking was done. In some poorly ventilated corners, we even found light mould starting to form.

If your kitchen is open to the living or dining area, a ductless chimney can work fine, since the humidity spreads out into the bigger space. But for a closed kitchen — which is what most Delhi NCR flats have — ducted is almost always the smarter long-term choice for your cabinets.

What It Costs

A mid-range 60cm ducted chimney unit costs around ₹8,000–15,000, plus ₹2,000–4,000 for installation, and another ₹3,000–6,000 if ducting work is needed. A ductless chimney starts cheaper — ₹6,000–12,000 for the unit and ₹1,000–2,000 for installation — but the charcoal filter needs replacing every 6–12 months, at ₹1,500–3,000 each time.

Here’s the interesting part: over 5 years, the total cost usually ends up almost the same for both — somewhere between ₹14,000 and ₹26,000. So price alone shouldn’t be your deciding factor. The real difference is in how the kitchen actually feels day to day.

Understanding Suction Power

Chimney suction is measured in cubic metres per hour (m³/h). For Indian cooking, aim for at least 1200 m³/h in a ducted chimney and 1400 m³/h in a ductless one — the higher number for ductless is because air has to pass through two filters, which slows it down. A cheap 900 m³/h chimney will disappoint anyone who cooks tadka daily, especially in a closed kitchen. Spending an extra ₹3,000–5,000 on a stronger model is worth it.

Noise and Upkeep

At the same suction level, ducted chimneys tend to run a bit quieter, since the motor doesn’t have to push air through as much resistance. The difference is small — maybe 3–5 decibels — but you’ll notice it if you spend a lot of time in the kitchen.

Both types need the mesh filter cleaned weekly with warm soapy water. Ductless chimneys need one more thing: the charcoal filter swapped every 6–12 months, closer to 6 months if you cook three meals a day at home. This is an ongoing cost people often forget to plan for. If tracking filter dates sounds like a hassle, it’s usually covered under our Annual Maintenance Contract (AMC) too.

Our Honest Recommendation

If your flat has access to an outside wall for ducting, go with a ducted chimney — most Delhi NCR apartments built after 2010 have this option. Choose ductless only if ducting truly isn’t possible (some high-rise or basement kitchens face this), or if your kitchen is fully open to the living room.

Whichever one you choose, don’t compromise on suction power — stick to 1200 m³/h minimum for ducted and 1400 m³/h for ductless. And if you go ductless, set a phone reminder to replace the charcoal filter every 6 months, or the chimney will stop doing its real job.

People often ask why ducted chimneys need an outside wall — it’s simple, the pipe has to exit somewhere. And what happens if you skip the charcoal filter replacement? The chimney keeps running and still catches oil, but the smell starts circulating back into the room, and the motor works harder — which means more noise and higher power bills.