Home Tap to Call Now

Why You Should Close Your Damper in the Summer

chimney damper


What do you do with your fireplace damper in the summer? Some people close it. Others leave it open. Others forget all about it, and it stays in whatever state it’s in until the next burning season. Of these three answers, the first is by far the best.

Whether it’s a top-sealing damper that opens and closes at the exterior-top of the chimney, or a throat damper, which creates its seal just above the firebox, dampers are designed to do two important things during the annual cycle of a fireplace: open to allow smoke to draft, and close to prevent the passage of air between the home and the outside world.


Problems with leaving the damper open in warmer months

Two primary myths lead some people to keep their fireplace dampers open during the hot months of the year. One myth says, with an open damper, warm air, which naturally rises, will move up the chimney and out of the house. The opposite is true: an open damper with no dense smoke running up it can allow hot air from outside to come right down the chimney and into the room.

The second myth is that an open damper will keep air circulating in the chimney and dry out any residual moisture. The fact is, hot weather – especially when it’s humid – adds to the moisture in creosote and soot in the chimney and leads to foul odors entering the home.

Good reasons for keeping your damper closed when a fire isn’t burning

1. In the summer, a closed damper helps to keep cool, air-conditioned air inside the home where it belongs.

2. In the winter, when you’re not using the fireplace, a closed damper helps to keep cold air from swirling down into the house.

3. Depending on how hot/cold it is where you live, numbers 1 and 2 can significantly reduce your cooling and heating bills.

4. Creosote and soot in a chimney release strong, unpleasant odors when the external temperature warms up. Closing the fireplace damper keeps these odors out of the house. (Annual chimney cleaning takes this a step further by removing the substances that cause the odors.)

5. If you don’t have a chimney cap – or have one that is in disrepair – a closed damper will prevent twigs, leaves, rainwater, small animals and more from moving down the chimney and into your home.

The challenge with chimney dampers

closed chimney damper

Because you can’t see either type of chimney damper from inside your home, it’s easy to forget to close it. (Remembering to open it when using the fireplace is easy when smoke starts backing up into the house.)  A good idea to help you keep track of the state of your damper is a little sign you can hang by the fireplace, with one side reading “DAMPER OPEN” and the other “DAMPER CLOSED.”  Simply keep the sign flipped to the side that tells you the damper’s state.

Chimney Specialists of Highland, WI, provides the very best in certified chimney sweep, chimney repair, chimney inspection and fireplace and stove installation services. We’re here to make sure every component of your chimney/fireplace system is in top working order and safe for you and your family. To inquire about any of our services or get your questions answered, reach us at (608) 929-4887.

Share Button