Term it Right: Flue, Chimney, or Vent

Chimneys, Vents, and Flues aren’t the same. If you’ve been using these terminologies interchangeably, it’s time you learn how to use them correctly. They don’t just have different names but also serve a slightly different purpose. It’s important to understand what each does.


A chimney is a vertical passage extending out of your roof that allows combustion products to exit your home. It can vent any type of fuel. Some of the chimneys pass through other parts of the house. Chimneys are built using brick, mortar, and masonry. These can also be made in factories using stainless steel. These steel chimneys are often covered by a chase for decoration, protection, or both.

A chimney functions on the principle of hot air rises, which is also called the stack effect. As you start a fire in the fireplace, the air in the chimney warms up and starts to rise out of the chimney, creating a pressure difference between the chimney and the room. The air from the room is sucked into the fireplace to maintain the pressure, feeding the fire as it moves past it.


A flue is simply a passage through which smoke, gas, and other combustion by-products can exit. These can either be pipes, vents, or chimneys. Most places with a fireplace have a lined flue that helps improve safety, increase efficiency, and keep the flue clean.

These flue liners must be inspected regularly to ensure that your home is secure against deadly combustibles and potential chimney fires.


Vents also help you remove the by-products of combustion from your home. Unlike chimneys, they require temperature protection and are, therefore, not suitable for wood-burning fireplaces.

Vents may have a vertical or horizontal exit. Like chimneys and flues, vents also function based on the hot air rises principle, drawing air into the fireplace.

 gray pipes on a building wall

Other Similar Vocabulary

Chimney or Flue Liners

If you’re new to the world of chimneys and flues, you might not know that the chimneys and flues are lined from the inside with a material commonly known as a chimney or flue liner. A lot of people also have a misconception that masonry chimneys are simply made of brick. This isn’t true.

These bricks can provide room for combustible by-products to gather, which can lead to chimney fires. To keep chimneys and flues clean and safe, you need to use a chimney or flue liner.


Connectors are more commonly known as smoke pipes. As the name implies, it carries smoke from a fuel-fired appliance to a vent or a chimney to remove them.

Chimneys, Flues, and Vents can still be a little tricky to understand. If you need any chimney, vent, flue, HVAC equipment-related inspection done, contact HTX Home Inspections. We’re certified home inspector that provides real estate inspection, property inspections, and residential inspection services Houston, Texas. For more details about our service, visit our website. You can also call us to book your inspection appointments on (281) 816-7007.