A range hood that disappears into your cabinetry gives you powerful ventilation without a bulky metal chimney breaking up the kitchen. A built in range hood, sometimes called an insert or a hood liner, tucks the blower and filters up inside a custom cabinet or a decorative cover so all you see is the underside. Choosing a built in range hood comes down to matching the airflow to your cooktop and planning the ducting before the cabinet goes in. This guide covers CFM sizing, ducting, insert types, and installation.
What a Built In Range Hood Is
A built in range hood is the ventilation guts, the blower motor, filters, and controls, designed to be installed inside an enclosure rather than hung as a finished unit. The enclosure might be a custom wood hood matching your cabinets, a plaster cove, or a standard upper cabinet. This lets you match the hood to any kitchen style while still getting real ventilation performance.
These inserts differ from under-cabinet or wall-mount chimney hoods, where the housing is the finished look. With an insert, a cabinetmaker or the homeowner builds the visible surround, and the metal liner slides up inside it. The result is a seamless, custom appearance that reads as furniture rather than an appliance.
Sizing the CFM to Your Cooktop
The most important number is CFM, the cubic feet of air the hood moves per minute. Undersize it and grease and steam linger; oversize it and you waste energy and may pull conditioned air out of a tight house. The right size depends on your cooktop’s output.
A widely used guideline is 100 CFM for every 10,000 BTU of gas cooktop output, or roughly 100 CFM per linear foot of cooktop width. Practical benchmarks:
- Standard 30 inch electric or modest gas range: 300 to 400 CFM is plenty.
- 36 inch gas range: 400 to 600 CFM.
- High-output or professional gas range: 600 to 1,200 CFM, sized to the total BTU rating.
- Cooktop with a grill or wok burner: lean toward the higher end for heavy smoke and grease.
Match the hood width to the cooktop or go one size wider. A hood that is a few inches wider than the cooktop on each side captures rising smoke that drifts to the edges, which is why many pros recommend a 36 inch insert over a 30 inch cooktop.
Ducted vs Ductless
How the hood handles the air it captures is a major decision. A ducted, or vented, hood pushes air through a duct to the outside, carrying grease, moisture, and odors out of the house entirely. This is the far better option for cooking performance and for keeping humidity out of your kitchen.
A ductless, or recirculating, hood pulls air through a charcoal filter and blows it back into the room. It removes some odor and grease but does nothing for heat and moisture, and the charcoal filters need replacing every few months at 20 to 50 dollars a set. Use ductless only when running a duct is truly impossible, such as an interior island in a slab home. Whenever you can vent to the outside, do it, because a ducted built in hood simply performs better.
If you cook often or run a gas range, the difference is not subtle. A ducted hood carries away the water vapor that a boiling pot or a simmering sauce throws into the air, which protects your cabinets and paint from the sticky film that recirculating hoods leave behind. It also removes combustion byproducts from a gas burner instead of recirculating them, which is a genuine indoor air quality benefit. For a serious cook, the choice between ducted and ductless is really a choice between a hood that works and a hood that mostly makes noise, so run that duct to the outside whenever the layout allows it.
Planning the Ductwork
Ducting is where built in hoods succeed or fail, and it has to be planned before the cabinet is built. The duct size, length, and number of turns all affect performance. Airflow drops with every elbow and every foot of run, so the shortest, straightest path to the exterior gives the best results.
Key ducting rules to follow:
- Use rigid metal duct, not flexible foil, which chokes airflow and traps grease.
- Match the duct diameter to the hood’s spec, commonly 6, 8, or 10 inches. A high-CFM hood needs a larger duct.
- Keep the run short and minimize 90-degree elbows; each elbow adds resistance equal to several feet of straight duct.
- Terminate at an exterior wall or roof cap with a damper to stop backdrafts.
Never vent a range hood into an attic, soffit, or crawl space. Dumping grease-laden, humid air into those spaces causes moisture damage and creates a fire risk over time. The duct has to reach the outdoors.
Mounting Height
Hood height above the cooktop balances capture performance against clearance for tall cooks. For most built in hoods, mount the bottom edge 30 to 36 inches above an electric cooktop. Gas ranges usually call for the same range, but always follow the specific hood’s manual, since a powerful hood may allow a higher mount.
Mount too high and the hood loses smoke to the sides before it can capture it; mount too low and you cut headroom and risk heat damage to the liner. The 30 to 36 inch window is the sweet spot for capturing rising smoke while leaving room to work at the stove.
Filters and Features
Built in hoods use baffle or mesh grease filters that catch airborne grease before it reaches the blower. Stainless baffle filters are the better choice because they trap grease efficiently and are dishwasher safe, whereas aluminum mesh filters clog faster and need more frequent cleaning. Plan to wash the filters every few weeks with regular cooking.
Grease that is allowed to cake on the baffles chokes airflow and, worse, becomes fuel for a fire directly above your cooktop, so cleaning is a safety task as much as a housekeeping one. Pull the baffle filters every few weeks, soak them in hot water with a degreasing dish soap, and run them through the dishwasher if the manufacturer allows it. A clean filter noticeably improves how much smoke the hood actually captures compared to one glazed with old grease.
Useful features to look for include multiple fan speeds, a boost setting for heavy cooking, LED task lighting over the cooktop, and a heat sensor that ramps the fan automatically. Quieter operation is rated in sones; a hood around 1 to 3 sones on low is comfortable, while high speed on a powerful unit will always be loud. If a hood is loud even on low, the cause is often the ducting rather than the blower, since crushed or undersized flex duct forces the motor to roar. Compare the sone rating on low and medium, since that is where you run it most, and know that a remote or in-line blower mounted out in the duct run is the quietest option of all. Consider a model with a delayed shutoff so the fan keeps clearing the air after you finish cooking.
Installation Planning
Installing a built in range hood usually involves three trades worth of work: carpentry for the enclosure, ducting, and electrical. The cabinet or custom hood surround has to be sized to the liner’s exact dimensions, so order the insert first and build the enclosure around its published measurements. A liner that does not fit its cabinet is a frustrating and expensive mistake.
The blower needs a dedicated electrical connection, and a high-CFM hood may require its own circuit. Electrical work must meet local code, and running a new circuit is a job for a licensed electrician. Likewise, if a very powerful hood over 400 CFM is installed in a tightly sealed home, code may require makeup air, a system that brings replacement air into the house so the hood does not create negative pressure that can backdraft a furnace or water heater. That is a real combustion-safety issue, so confirm makeup air requirements with your installer or local code before choosing a large hood.
Cost Expectations
The insert itself typically runs 200 to 800 dollars for a standard unit and 800 to 2,000 dollars or more for a high-CFM professional liner. The custom cabinetry or hood surround adds anywhere from a few hundred dollars for a simple cabinet to a couple thousand for an ornate plaster or wood hood. Ducting materials run 50 to 200 dollars, and professional installation with electrical and ducting often adds 400 to 1,200 dollars.
Get the CFM, the duct path, and the enclosure dimensions settled before anything is built, and a built in range hood gives you the clean look of custom cabinetry with the muscle to keep your kitchen air clear. Confirm the exact liner specs on the manufacturer’s page, since dimensions and CFM vary by model, and build around those verified numbers.
