Commercial Ventilation Hoods: A Buyer’s Checklist for Kitchens

A commercial ventilation hood captures grease, heat, smoke, and fumes from cooking equipment, and the correct one depends on what you cook, how large your cooking line is, and what your local code requires. The central decision is Type I (grease-producing) versus Type II (heat and steam only). Because fire and health codes apply, treat this as a purchase to plan with your mechanical contractor and local authority, not a casual online order.

Type I vs. Type II Hoods

Type I hoods are for cooking equipment that produces grease-laden vapors, such as fryers, griddles, charbroilers, and ranges. They include grease filters or baffles and typically require a fire suppression system. Type II hoods handle heat, steam, and odors from items like dishwashers and pizza ovens without grease, as determined by code. Using the wrong type is a compliance risk, so confirm classification with your inspector before choosing.

Size, Overhang, and Capture

The hood should be longer and wider than the equipment beneath it. Common practice is an overhang beyond the appliance edges, often several inches on each open side, though the requirement depends on code and hood type. Hood height above the cooking surface also affects capture. Too high and fumes escape; too low and it interferes with the cook. Consult the hood’s listing and a qualified designer to determine dimensions.

Exhaust airflow is measured in cubic feet per minute (CFM). Equipment type and hood style determine the required CFM per linear foot. A restaurant with heavy grill use will need substantially more airflow than a bakery with a light-duty oven. Undersizing leaves smoke in the kitchen, and oversizing wastes energy and creates drafts.

Makeup Air and Fan Selection

What goes out must come in. A hood that exhausts large volumes of air requires a matching supply of makeup air, or the kitchen becomes negative-pressure, causing doors that are hard to open, backdrafting, and poor capture. Plan makeup air with the hood, not as an afterthought. Choose an exhaust fan rated for grease duty if cooking produces grease, with an access panel for cleaning, and check noise levels. An upblast fan on the roof is common; inline and wall-mounted fans suit certain layouts. Variable-speed controls can save energy when cooking intensity changes.

Construction and Materials

• Stainless steel: typically 18-gauge or heavier for durability and cleanability.
• Welded seams: liquid-tight welds are normally required for grease ducts.
• Filters or baffles: baffle filters are common in Type I hoods and are dishwasher-washable.
• Lighting: listed, vapor-proof fixtures improve visibility for cooks.
• Listings: look for evidence that the hood is listed for its intended use by a recognized testing agency.

Shoppers researching equipment types can start with stainless steel commercial kitchen exhaust hoods, but all specifications must be confirmed with your local code officials.

Fire Safety, Code, and Professionals

Commercial cooking falls under fire and mechanical codes, often based on standards such as NFPA 96 and the International Mechanical Code, adopted with local variations. These govern grease duct design, clearances to combustibles, fire suppression, and cleaning schedules. Hire licensed contractors for ductwork, fire suppression, and electrical connections, and obtain required permits and inspections. Ask the health department and fire marshal what they require before purchasing.

Plan for routine cleaning. Filters need frequent washing, and ducts require periodic professional cleaning at intervals set by code and usage. Keep records, since inspectors and insurers may request them. A commercial hood filter degreaser is useful for daily and weekly upkeep, but it is not a substitute for professional duct cleaning.

Get the budget picture early. The hood is only one line item: ductwork, a fan, makeup air equipment, fire suppression, installation labor, permits, and inspections often add up to more than the hood itself. Request itemized quotes from licensed contractors, and ask which costs your landlord or building may cover. Used hoods can save money, but make sure they meet current code and that the listing and dimensions match your equipment.

Energy cost is another long-term factor. Exhaust fans remove conditioned air, so heating and cooling bills rise with airflow. Demand-controlled ventilation systems, which adjust fan speed based on cooking activity, can reduce this load in many kitchens, and some utilities offer incentives. Ask your designer about heat recovery or low-flow hood designs, too.

Finally, think about the cooks. A hood that is too low, too noisy, or poorly lit makes the line harder to work. Ask staff for input on lighting, reach, and noise before finalizing the layout. A well-designed system is one the team can operate and clean easily.

Frequently Asked Questions

Can I use a residential hood in a commercial kitchen?

Generally no. Commercial cooking typically requires listed commercial equipment and compliance with commercial codes. Ask your local authority.

How do I know the right CFM?

Required airflow depends on the hood style, equipment, and code. A mechanical engineer or hood manufacturer can calculate it for your line.

Do I need a fire suppression system?

For grease-producing cooking, codes commonly require an automatic suppression system tied to the hood. Verify requirements with your fire marshal and a licensed installer.