From the Manualdamper

We want to help homeowners get a handle on the damper, one of the most misunderstood features of the fireplace, but so vital. If the damper is not functioning correctly or if it’s closed, you’ve got a situation on your hands that may lead to a smoky room at best and a fire hazard at worst.

At the Chimney Safety Institute of America, or CSIA, we teach chimney sweeps about use of dampers in fireplaces. (We used the definitive guide in the industry, our Successful Chimney Sweeping manual. Many of those lessons are also applicable for homeowners!

The damper is a hinged metal plate or valve used to seal the fireplace when it is not in use. In a masonry fireplace, the damper is usually located at the throat of the fireplace, the intersection of the firebox assembly and the smoke chamber assembly. It’s just of out of sight, but easy to reach.

A traditional damper for a masonry fireplace.

A traditional damper for a masonry fireplace.


In factory-built fireplaces, which are constructed as a single unit, dampers often consist of a round blade on a rod and they open and close by means of a handle located inside the firebox or mounted outside the fireplace.

To inspect the damper, you usually have to crouch down and peer upward toward the rear of the fireplace. A flashlight will help. Pushing on the lever, or perhaps sliding it back or forth, opens/closes it.


The lever on this damper moves left to right.


MORE: A CSIA video: How to open or close your fireplace damper.

“Almost everyone who has had a fireplace at one time or another has forgotten to open the damper and smoked up the room,” said Ashley Eldridge, CSIA Director of Education. “You want the damper to be fully open, and you want it to be in the open position before you light your fire, for obvious safety reasons.”

All factory-built (or manufactured) appliances come with manufacturers’ instructions, but you can ask your CSIA Certified Chimney Sweep for advice on how to operate yours safely.

Then you can light your fire with confidence, knowing that the smoke will go up the chimney.

how to open and close fireplace damper

The lever on this fireplace moves back and forth.

Although there are a variety of different dampers, they should be completely open before the fire is started and completely closed after the fire. Soon, we’ll share more stories in our “From the CSIA Manual” series.