Range hoods work either way, but ducted models that vent outside remove more heat and odor

A range hood does not have to vent outside. You can install a ductless (recirculating) hood that filters air and pushes it back into your kitchen, or a ducted hood that runs a pipe through your wall or ceiling to the outdoors. Ducted hoods pull steam, grease, and cooking smells out of the house entirely. Ductless hoods trap grease in a filter and pass cleaned air back inside, which means some moisture and heat stay in your kitchen.

The choice depends on your kitchen layout, how much you cook, and whether your walls allow for ducting. If you cannot run ductwork to an exterior wall or roof, ductless is your only option. If you can duct to outside, a ducted hood will perform better and last longer because it removes the moisture that damages cabinets and walls over time.

Key Takeaways

  • Ducted hoods vent to the outside and remove heat, moisture, and odors completely; ductless hoods filter and recirculate air back into the kitchen.
  • Ductless hoods are easier to install in apartments or homes where running ductwork is not possible, but they require more frequent filter changes.
  • Ducted hoods cost more to install but perform better and prevent moisture damage to cabinets and walls over years of cooking.
  • Your kitchen layout, cooking frequency, and building structure determine which type works for your space.

How ducted hoods remove moisture and odor

A ducted hood pulls air directly from above your cooktop and sends it through a metal duct to the outside of your house. The duct typically exits through a wall behind the stove or through the ceiling and roof. As the hood runs, it removes steam, cooking odors, grease particles, and heat before they spread through your home.

This matters because cooking steam condenses on walls, cabinets, and windows over time. That moisture can warp wood, peel paint, and create conditions for mold. A ducted hood stops this before it starts. The grease that would otherwise settle on surfaces instead travels outside in the ductwork. You still need to clean the hood's filter, but the bulk of the work happens outside your living space.

Ducted hoods are rated by CFM (cubic feet per minute), which measures how much air they move. A hood rated 300 CFM moves 300 cubic feet of air per minute. Higher CFM means faster removal of smoke and steam, which is useful if you cook frequently or use high heat.

How ductless hoods filter and recirculate air

A ductless hood pulls air through a filter and pushes it back into your kitchen. The filter traps grease and some odor particles, but not all of them. Some smell lingers in the air, and the heat and moisture from cooking stay in your kitchen instead of leaving the house.

Ductless hoods use either a mesh or charcoal filter. Mesh filters catch grease; charcoal filters absorb odors. Many ductless models use both in layers. You must clean or replace these filters every one to three months, depending on how often you cook. A ducted hood's filter needs cleaning less often because most of the grease exits through the duct.

Ductless hoods are cheaper to install because they do not require ductwork, and they work in any kitchen layout. They are common in apartments, condos, and rental homes where running ductwork through walls is not allowed. The trade-off is that they do not remove moisture, so your kitchen stays warmer and more humid after cooking.

Installation differences and costs

Installing a ducted hood requires running ductwork from the hood to an exterior wall or through the roof. This means cutting holes, routing the duct, and sealing it against weather. If your kitchen is on an exterior wall, the job is straightforward. If your stove is on an interior wall, the duct must run a longer distance, which costs more and reduces airflow.

A ductless hood plugs in and sits on the wall or under a cabinet. No ductwork, no holes in the roof. Installation takes a few hours and costs far less. The downside is that you are responsible for filter maintenance, and the hood will not remove as much heat and moisture.

Ducted hoods typically cost $300 to $1,000 for the unit itself, plus $200 to $800 for professional installation and ductwork. Ductless hoods run $200 to $600 for the unit and $100 to $300 to install. Over time, a ducted hood saves money on filter replacements and prevents moisture damage that would otherwise require cabinet or wall repair.

When ductless is your only option

If you rent, live in a condo with shared walls, or cannot cut through exterior walls, ductless is what you can install. Some buildings do not allow holes in the roof or exterior walls because of structural or aesthetic rules. Ductless hoods work in these situations and are better than no hood at all.

The performance gap matters less if you cook light meals occasionally. If you boil water, fry food, or cook with high heat several times a week, a ducted hood will make a noticeable difference in how your kitchen smells and feels. For light cooking, a ductless hood handles the job adequately as long as you change the filters regularly.

When ducted is worth the extra cost

If you own your home and your stove is on an exterior wall, ducted is the better choice. The installation cost is one-time. The benefit — no moisture damage, no lingering odors, lower filter maintenance — compounds over years. Kitchens with ducted hoods stay drier and smell fresher.

Ducted hoods also add resale value. Buyers see a ducted hood as a sign that the kitchen was built to last. A ductless hood, while functional, signals that the kitchen was not designed for serious cooking or long-term durability.

If you cook frequently, use your stove for high-heat cooking, or plan to stay in your home for more than five years, the ducted hood pays for itself in comfort and avoided repairs.

Ductwork materials and sizing

Ducting comes in rigid metal (aluminum or galvanized steel) or flexible metal. Rigid duct is more efficient because it has fewer bends and less friction, so air moves faster. Flexible duct is easier to install around obstacles but slows airflow slightly. Most installers use rigid duct where possible and flexible duct only where needed.

The duct diameter matters. Most residential range hoods use 6-inch or 8-inch diameter duct. A 6-inch duct works for hoods up to about 400 CFM. Larger hoods need 8-inch duct to avoid excessive noise and pressure loss. If your duct is too small for your hood's CFM, the hood will work harder, run louder, and move less air.

Ductwork should slope slightly toward the outside to prevent condensation from running back into the hood. It should also have a damper (a flap that closes when the hood is off) to prevent cold air from leaking back into your kitchen in winter.

Frequently Asked Questions

Can I use a ductless hood if I have a ducted hood already installed?

Yes. You can remove the ducted hood and install a ductless one in its place. You will lose the performance benefit of ducting, but if your ductwork is damaged or your building rules change, ductless is a working alternative. Seal the hole where the old duct exited to prevent drafts and pests.

How often do I need to clean the filter on a ducted hood?

Once every two to three months for light cooking, or monthly if you cook frequently or use high heat. A ducted hood's filter catches less grease than a ductless hood's because most grease exits through the duct. Check the filter visually; if it looks dark or clogged, clean it sooner.

Does a ductless hood work if I live in an apartment?

Yes, ductless hoods are designed for apartments and rentals. They do not require holes in walls or ceilings, so they comply with most lease agreements. Check your lease or ask your landlord before installing any hood, but ductless models are almost always permitted.

What happens if I block the duct on a ducted hood?

The hood will not work properly. Airflow will drop, noise will increase, and steam and odors will not exit the kitchen. A blocked duct usually means a damper is stuck closed, the duct has a kink, or debris is clogging the exit. Check the damper first, then inspect the duct for damage or blockage.

Is a ductless hood better than opening a window?

A ductless hood removes more grease and odor than an open window because it filters the air. An open window removes heat and moisture but does not trap grease, which settles on your cabinets and walls. A ductless hood is more effective, but a ducted hood is more effective still.