Kitchen ventilation: the questions to settle before choosing a hood

Why ventilation is a layout decision

Cooking produces moisture, grease, odors and fine particles, and gas burners add combustion products. EPA's indoor air guidance says that using a stove hood with a fan vented to the outdoors greatly reduces exposure to pollutants during cooking. It recommends turning the hood on whenever you cook, leaving it on for 10 to 20 minutes afterward and cooking on the back burners when possible.

Those habits only help if the hood can do its job, and that depends on where the cooktop sits. A range on an outside wall is usually simpler to vent than one in an island or in the middle of a two-family house's interior. Settle the ventilation question while the layout is still flexible, alongside kitchen layout and storage planning.

Ducted or ductless: what the codes say in broad terms

In New York City, the NYC Mechanical Code addresses domestic range hoods, ductless hoods and makeup air (Sections 505.1 and 505.2); ask the design professional how it applies to your kitchen.

In Suffolk County and the rest of the state, residential work falls under the New York State Uniform Code. The Department of State's notice says the 2025 Uniform Code, including the 2025 Residential Code of New York State, took effect on December 31, 2025, with a transition period in which applicants could choose between the 2025 and 2020 editions. This guide did not quote that code's kitchen-exhaust provisions; your town or village building department and the design professional apply them.

Makeup air and gas appliances

Every cubic foot of air a hood pulls out has to be replaced from somewhere. In a tight house, a powerful exhaust fan can make it harder for other appliances that rely on natural draft to vent properly. EPA notes that pollutants from fireplaces and woodstoves with no dedicated outdoor air supply can be back-drafted into the living space, particularly in weatherized homes.

• Ask whether the hood you like triggers a makeup-air requirement under the code that applies to your house.
• List every fuel-burning appliance in the house, including the boiler or furnace, water heater, fireplace and dryer, and ask how the hood affects them.
• If makeup air is required, ask how it will be provided and controlled, and include it in the scope and the estimate.
• Keep gas burners properly adjusted. EPA notes a persistently yellow-tipped flame suggests improper adjustment and advises asking the gas company to adjust it; this is not a household task.

Questions to settle before you order a hood

1. Will the hood exhaust outdoors, and what route can the duct take to an outside wall or roof?
2. In a two-family house, does that route pass through the other unit or a shared space?
3. Does the planned hood or cooking appliance raise a makeup-air question under the code that applies to your house?
4. Which fuel-burning appliances share the house, and has their venting been considered?
5. Who designs the system and who installs it? Ductwork, wall or roof penetrations, wiring and any gas work belong to the appropriate licensed trades.
6. Does the estimate list the hood, duct, exterior termination, makeup air (if any) and any patching and finishing separately?

Line those items up when you compare remodeling estimates, so one proposal's hood isn't priced without the duct and another's with it.