What Is a Smoke Shelf in a Chimney and How Is It Used?
No need to worry about downdrafts thanks to this ledge
A smoke shelf is an important part of a chimney that helps prevent strong downdrafts from blowing into your home.
A smoke shelf also prevents water and debris from entering your house.
You may be able to clean the smoke shelf yourself, but if it’s hard to reach or you can’t see it, it’s better to call a pro.
A chimney is made up of several parts that help it work safely and efficiently, keeping dangerous smoke from entering the house. The smoke shelf within your chimney may be simple enough: It’s essentially an outstretched ledge that is both a fire barrier at the throat of your chimney and a draft deterrent for wind entering your chimney. Let’s take a closer look at how this component works and how to maintain it.
What Is a Smoke Shelf and How Does It Work?
A smoke shelf is a small ledge that slightly juts out within your chimney. The top portion of it either lays flat or curves toward the flue. It’s typically located behind your fireplace as a slightly angled wall and continues above the fireplace, with the actual shelf inside the smoke chamber. Typically, a smoke shelf is made of brick, though some chimneys may use ceramic tile or rubble.
A smoke shelf redirects cold air and catches water and debris. When you have the chimney damper open, cold air comes into the chimney and hits the smoke shelf. It’ll mix with the warm, smoke-filled air from your fireplace, and then help carry the smoke and warm air out of the chimney so that it doesn’t go back into your home.
It can also catch water if it’s raining or snowing or leaves or other debris if it’s windy outside. This prevents water or debris from unexpectedly hitting your fireplace.
Does My Chimney Need a Smoke Shelf?
If you don’t have a smoke shelf in your chimney, this can cause issues with drafts coming into your home and possibly bringing lots of smoke. The ledge part of the smoke shelf is installed directly behind your fireplace and typically works as both a thermal barrier and a way to direct the smoke through the chimney damper. Without it, you may have a draftier home, and smoke and toxins from the fire may blow inward if there’s a strong downdraft.
What Are Some Signs My Smoke Shelf Is Damaged?
Your smoke shelf may be damaged if you notice your home is draftier than usual. This can be caused by a number of reasons within the smoke chamber itself, including cracks within the masonry, creosote buildup, or damage to the smoke shelf and liner.
Though a chimney inspection costs about $450 on average, it’s worth it to hire a chimney repair pro near you who can give you peace of mind and make the necessary repairs before any damage happens to your home.
You can clean a smoke shelf using either a bendable brush and dustpan or a shop vacuum with an attachment. You need to be very careful when cleaning and allow the dust to settle so that it doesn’t blow soot and dust from the shelf into your home. You should wear protective coverings such as a mask, goggles, and gloves so that you don’t inhale or ingest large amounts of soot.
You may be able to clean your smoke shelf yourself, though it depends on whether you can reach the shelf with the tools you have. If you cannot see through the chimney damper to the shelf, it’s better to rely on a professional chimney specialist. It’s also wise to get a professional if you see creosote buildup, which is typically hard, shiny, and sometimes sticky. A pro has the correct tools and safety equipment to properly clean out the chimney.
