When you light a fire in your fireplace, you enjoy the warm, crackling blaze. …but you probably don’t often consider that behind the scenes, there’s a lot going on to keep that fire going and pull its harmful byproducts safely away. As a matter of fact, there’s a whole system in place to make sure everything works smoothly – like the chimney cap, the smoke chamber, and – of course – the chimney flue.

If your system needs care, don’t hesitate to book your next chimney service with us. We’re just a click or phone call away.

Chimney vs. Chimney Flue: What’s the Difference?

One important, hidden component is your chimney flue. If you have a fireplace, you’ve probably heard the term flue before. While it’s sometimes used as a synonym of chimney, the two words actually refer to two distinct (but related) things.

  • Your chimney is the whole structure (and its parts), encompassing everything from the top of the smoke chamber to the top of the chimney cap.
  • Your flue is the pathway inside the chimney through which smoke and combustion gases are vented. The flue is contained in the chimney, and the chimney contains more parts than the flue alone.

Think of your chimney as a house. Your flue would be like an interior hallway providing access from room to room throughout the house and to the outdoors.

Another potentially tricky term is chimney liner. Also located inside the chimney, the chimney liner provides protection for the flue from the high temperatures and corrosive qualities of combustion byproducts. Usually, a chimney liner will be made of smooth, durable, heat-resistant materials like ceramic tile or stainless steel.

original infographic outlining some chimney anatomy to show the difference between a chimney and a chimney flue

The Importance of Maintaining the Chimney Flue

Your chimney flue is out of sight, but maintaining it and investing in regular sweeping services is crucial. Why?

  • To promote good ventilation. A chimney with a clear, well-maintained flue can move dangerous gases like carbon monoxide safely outside and keep smoke from billowing back into your house.
  • To prevent downdrafts. A well-functioning flue helps prevent cold air from coming into your living space via your firebox.
  • For fire safety. In the course of using the flue, creosote can build up on its walls. Since this is a combustible material, creosote accumulation can lead to chimney fires. A clean flue reduces this risk.

How Does the Chimney Flue Work With Other Chimney Components?

To have a functional fireplace, you need all parts of the fireplace and chimney working well. If the flue (or any other component) is not in good repair, it can negatively impact the functionality, efficiency, and safety of the whole system. But when they’re kept clean, clear, and well-maintained, it’s a thing of beauty!

  • The firebox is the chamber that hosts the actual fire. Once you start the fire – whether by switching on a gas unit or putting a match to kindling in a wood-burning one – the magic begins. Warm air begins to rise, carrying with it smoke and gases.
  • Before the smoke can rise up the flue, however, it needs to pass through the damper. The damper is a plate that helps regulate airflow within the chimney. You can open it to allow smoke to flow up the chimney and new oxygen to move in to feed the fire, or close to seal up your home when the fireplace isn’t in use.
  • While you need to allow passage for smoke and air to move, you also don’t want significant downdrafts to blast into the firebox. The smoke shelf is a flat surface that protects against this, and it also keeps debris from entering the fireplace. The smoke shelf, plus the sloped walls of the smoke chamber above it, help direct smoke into the flue.
  • The flue is like the highway of your chimney system. Its size and materials ought to have been thoughtfully engineered to channel smoke and gases safely up and out of the house. Keeping smoke, gases, and particulates out of your living space is vital to protect the air quality in your home and keep your home a safe, pleasant place to be.
  • When smoke reaches the end of its journey out of your home, it passes a couple more important chimney features. The chimney cap and crown are positioned at the top of your chimney stack. The chimney crown is a sloped slab that covers the chimney top, protecting the masonry below from moisture. The chimney cap is anchored to the very top of the system. It allows gases and smoke to vent while keeping the elements, wildlife, and debris out.

Reach Out Soon

Are you experiencing smoke in your home or other concerning symptoms? Maybe you know your chimney is about due to be relined, or more than a year has elapsed since your last professional inspection. Great chimney care is only a call or click away. We can help ensure that your chimney is operating the way it should from firebox to flue and smoke chamber to chimney cap. We’ll give you top notch service so your fireplace will serve you well for years to come!

Reach out now to get started.