How to Size a Range Hood for Your Kitchen

A beautiful range can anchor a luxury kitchen, but the wrong ventilation can undermine the entire experience. Lingering cooking odors, grease on nearby cabinetry, excessive heat, and a hood that sounds like an aircraft are often sizing problems, not product-quality problems. Knowing how to size a range hood means looking beyond appearance to the relationship between your cooking surface, airflow, ductwork, and kitchen layout.

For a Miami condominium kitchen, a waterfront home with an open entertaining space, or a new build with a professional-style range, the right answer is rarely just “buy the widest hood available.” A well-sized hood captures smoke and vapor at the source, complements the proportions of the room, and works within the building’s ventilation requirements.

Start With Range Hood Width

Width is the first sizing decision because it affects capture area. At a minimum, a range hood should be as wide as the cooking surface below it. A 30-inch cooktop needs at least a 30-inch hood, while a 36-inch range needs at least a 36-inch hood.

For many premium kitchens, especially those with gas or pro-style ranges, going wider is the better choice. A hood that extends 3 inches beyond each side of the cooking surface creates a larger capture zone. That means a 36-inch range often performs best with a 42-inch hood, provided the cabinetry, ceiling line, and installation plan allow it.

This recommendation matters even more with high-heat cooking. Searing, wok cooking, grilling on an indoor grill plate, and frequent use of front burners push heat and grease outward before the hood can pull them up. Extra width gives the hood a better chance to contain that plume rather than letting it drift into the room.

Island Hoods Need More Coverage

Wall-mounted hoods benefit from the wall behind the range, which helps direct cooking effluent toward the hood. Island hoods have no such advantage. Air can move in every direction, particularly in open-concept kitchens with ceiling fans, strong air conditioning, or wide paths to adjacent living areas.

For that reason, an island hood should generally be wider than the cooktop, often by 6 inches total or more. A 36-inch island cooktop may call for a 42-inch or 48-inch hood. The exact choice depends on the hood’s depth, blower performance, mounting height, and the way the household cooks.

How to Size a Range Hood by CFM

CFM, or cubic feet per minute, measures how much air a blower can move. More CFM can improve ventilation, but it is not automatically better. An oversized blower paired with poor ductwork, a shallow hood canopy, or an improper installation may be loud without delivering the capture performance you expect.

A practical starting point for electric cooktops is about 100 CFM per linear foot of cooking surface. Under this guideline, a 30-inch electric cooktop would begin around 250 CFM, while a 36-inch model would begin around 300 CFM.

Gas cooking requires more airflow because combustion adds heat, moisture, and byproducts to the air. A commonly used planning rule is 1 CFM for every 100 BTUs of total burner output. If a 36-inch gas range has 90,000 BTUs across all burners, a 900 CFM hood may be appropriate. However, that number should be evaluated alongside the hood canopy, duct run, and local code requirements rather than treated as a stand-alone specification.

Professional ranges often deserve special attention. A model with powerful burners may need 600 to 1,200 CFM or more, depending on its total BTU output and how it will be used. If the range is primarily used for light weekday cooking, the final selection may differ from a kitchen designed for frequent frying, searing, and large-scale entertaining.

Choose Capture Performance, Not Just a Big Number

CFM tells only part of the story. The hood must also be deep enough to cover the front burners, especially on a deep professional range. A shallow decorative hood may look refined but can struggle to capture steam and smoke from front burners, even with a high-powered blower.

Look at the canopy depth, filter design, blower configuration, and recommended mounting range. Premium ventilation brands often engineer these elements to work together. A properly designed 600 CFM hood can outperform a poorly matched 1,000 CFM model in real kitchen conditions.

Ductwork Can Make or Break the Installation

A range hood can move air only as effectively as the duct system allows. Long duct runs, undersized ducts, unnecessary elbows, and restrictive roof or wall caps reduce airflow and increase noise. This is a frequent issue in renovations where the new range is more powerful than the original ventilation plan.

Whenever possible, use smooth metal ducting with the diameter specified by the hood manufacturer. Higher-CFM hoods commonly require 8-, 10-, or even 12-inch ductwork. Connecting a powerful hood to a smaller existing duct may create back pressure, reduce real-world airflow, and put unnecessary strain on the blower.

Keep the route as short and straight as practical. Every turn adds resistance, and sharp 90-degree elbows are more restrictive than gradual bends. Exterior venting is generally the preferred option because it removes heat, moisture, odors, and airborne grease from the home rather than filtering and recirculating them.

In high-rise condominiums, exterior ducting may be limited by building design or association rules. A ductless or recirculating hood can be a design-forward solution where necessary, but it should be selected with realistic expectations. Recirculating systems can reduce odors and capture some grease through filters, yet they do not remove heat and humidity from the kitchen in the same way as a ducted hood. In South Florida, where humidity is already a daily consideration, that trade-off deserves careful discussion during planning.

Confirm Mounting Height and Hood Depth

Most residential range hoods are installed roughly 24 to 30 inches above an electric cooktop and about 27 to 36 inches above a gas range, but the manufacturer’s installation instructions always control. Mounting the hood too high weakens capture. Mounting it too low can interfere with cooking and may violate clearance requirements.

Ceiling height also matters. A 10-, 12-, or 14-foot ceiling may require a chimney extension or remote blower configuration, particularly with an island hood. More distance between the hood and cooktop often calls for more thoughtful sizing, because rising heat has additional time to spread before reaching the canopy.

Do not overlook hood depth. A 36-inch-wide hood over a 27-inch-deep professional range may not cover the front burners adequately if the canopy is only 18 inches deep. In those cases, a deeper hood, a larger canopy, or a different ventilation style may be the more effective upgrade.

Consider Makeup Air Before Selecting High CFM

Many jurisdictions require makeup air when a kitchen exhaust system exceeds a certain airflow threshold, commonly 400 CFM. Makeup air replaces the air removed by the hood so the home does not develop negative pressure.

Without adequate replacement air, a powerful hood can cause issues such as difficult-to-open exterior doors, weak performance, fireplace backdrafting, or pressure imbalances that affect air conditioning. This is particularly relevant in tightly built luxury homes with multiple exhaust systems, including dryers, bathroom fans, and whole-house ventilation.

The requirement and solution vary by municipality, building type, and code edition. It may involve a dedicated makeup-air damper, conditioned replacement air, or coordination with the HVAC contractor. Address this early in the design process rather than after cabinetry and finishes are complete.

Match the Hood to the Way You Cook

A household that heats prepared meals and occasionally sautés vegetables has different needs than one that regularly prepares steaks, seafood, fried foods, or multi-course dinners. The kitchen itself matters too. An enclosed kitchen can sometimes contain cooking byproducts more easily than a large open plan that flows into a dining room and living space.

A quiet hood with multiple blower speeds is often the most livable choice. It allows low-speed operation for everyday cooking and higher airflow when the menu demands it. Ask about sone ratings, remote or in-line blowers, baffle versus mesh filters, and how easily filters can be removed for cleaning. Luxury ventilation should support the way your home feels during a dinner party, not overpower the conversation.

For renovation and new-construction projects, bring the range model, kitchen plan, ceiling height, and any known duct details into the selection conversation. ITECH Appliances can help coordinate the product, delivery, professional installation, and technical considerations that turn a statement range hood into a dependable part of the kitchen.

The best time to solve ventilation is before the drywall closes and cabinetry is finalized. Give the hood the same attention you give the range beneath it, and every meal will leave behind the memory of the cooking, not the smell of it.