Does kitchen need exhaust fan? Read this Simple Explanation

kitchen vent circulation between cabinet

Ventilation in the kitchen is often overlooked, but most people don’t realize how important it is. People often say that the kitchen smells like cooking, but where there is the smell of good food, there are likely to be other, less pleasant smells as well. In short, no, you do not have to have an exhaust fan in your home kitchen.

There may be carbon monoxide fumes from burning natural gas, as well as tars and aldehydes that cause cancer. The extra moisture from boiling water or simmering soups can quickly fill your kitchen, and even a simple task like frying an egg releases toxic hydrogen sulfide into the air.

There are mouths to feed and an air vent in a healthy dining room or kitchen.

Kitchen exhaust fans are easy to use, cheap, and simple to set up. They lower the risks that come with having too much humidity. They are important, but they may not be enough.

Pollutants are sucked up by these systems right where they are made, and they are sent straight outside through vents. Natural ventilation brings in fresh air (called “compensation air”) through cracks in the building envelope or doors and windows.

In the kitchen, the fan should be able to move at least 50 liters per second, which is about 100 cubic feet per minute, and make a sound no more than 1.0 sone. If a fan is too loud, you won’t use it as often as you should. Set the hood up between 18 and 30 inches from where you cook.

What are the bad things about it?

  • A lot of stale air will leave the house through air extractors. On the other hand, infiltrations are not always enough to keep things in balance. If there is no way for more air to get in, the house could end up with low pressure. In this case, dangerous gases will get inside and hurt the people who live there. To avoid these risks, you can open the windows or add hatches that let air in and change the pressure balance, even though these steps can be expensive in the winter. If there is a central ventilation system, it will be important to make sure it is well balanced so that the flow rates of the air coming in and going out are the same.
  • People don’t have good control over airflow and humidity.
  • If there isn’t a way to get the heat back from the air taken out of the house, using them in the winter will make heating costs go up.

What is the kitchen exhaust fan price?

A range hood can cost anywhere from $50 to $600, depending on its quality and how much air it can move. On average, they live for 9 years. An ENERGY STAR model is also something we recommend. It usually costs about the same as other options, and it will save you a few kilowatt hours per year.

Models that cost more will be able to let out up to 280 L/s (600 cubic feet per minute). If your ventilation ducts have a lot of bends, there will be pressure drops in the system. This is because the friction of the air in the ducts wastes energy, so you will have to choose a more powerful model and pay more for the device and to run it.

Also, don’t choose a model with too much power to avoid problems with depressurization and save money on heating costs in the winter. Most of the time, 105 to 300 cubic feet per minute (50 to 140 L/s) is enough.

Models with carbon filters need to have their filters changed once or twice a year. About $50 is what they cost. For more traditional hood models, if you clean the aluminum filters now and then, they will last as long as the fan.

Automatic kitchen exhaust fans (self-venting)

Sometimes, appliance makers promoted vent hoods and microwave ovens with vents that were ductless, recirculating, or self-venting.

Simple recirculating fans with filters meant to catch grease and other particles were used in these units, but they did nothing to get rid of dangerous fumes like carbon monoxide. If the filters were not kept clean, they were pretty much useless.

This setup isn’t good enough anymore unless the kitchen also has a double-flow CMV system without ducts that send stale air outside. Even though you can always buy ventilation hoods that can be set up to be self-venting, the best way to use them is to adapt them for external ventilation.

There are different kinds of kitchen vent hoods

Hood with built-in ventilation:

These range hoods are attached to the bottom of a specially made wall cabinet. The cabinet has ductwork that comes out of a side wall or up through a soffit and then out the roof. This is a classic type of vent hood that you can find in a lot of kitchens.

Wall-mounted chimney ventilation hood:

This is a big hood with no cabinet on top. It is often used with commercial-grade ranges. It can be cooled or warmed by air coming in through the roof or a side wall. For this type of ventilation, you should choose a suction of at least 370 m3/h, but 650 m3/h is best if you cook dishes that are very greasy or smell bad.

Ventilation hood for an island:

Like wall hoods, these hoods are finished on all sides and are used to vent an island stove through the roof or a hole in the floor and then through a side wall.

When the cooktop is on an island, there is usually no direct way to get to it through a side wall or the roof. For this purpose, there are downdraft hoods with powerful fans that pull cooking vapors and exhaust fumes from gases downward into ducts that run under the floor and exit through a side wall. Because the ducts are so long, these fans tend to be very powerful.

High-Powered Microwave with Fan:

Some microwave ovens have an exhaust fan built into the cabinet. This saves space. Most of the time, these appliances are placed above the range or cooktop and are sold as “built-in” or “extended range” microwave ovens. Some types can be set up as exhaust fans with or without ducts. Most of these appliances have an exhaust capacity of 200–400 cfm, which is enough for most kitchens. Most of the time, they come with built-in filters and lighting.


Exhaust ventilation systems are a must in the kitchen and bathroom to get rid of most pollutants and moisture at their source. But they aren’t always enough. Then, a central ventilation system will be needed to finish bringing fresh air into the building and spreading it around. This will give you better control.