First, you’ll need the right tools. Measure your chimney flue, and purchase a brush that most closely matches its size and shape. You can find brushes at Lowes, Amazon.com, and specialized online chimney stores. They are usually between $20-50, depending on brand and size. You’ll also need chimney brush rods, enough lengths to reach the bottom of your chimney from the top. They are usually about 3 to 4 feet long and about $8 each. You’ll also need something to cover your fireplace opening to trap debris. If you have glass doors, close them. A garbage sack or sheet of plastic and some tape can help seal out debris as well if needed. You’ll probably want something to cover furniture and carpet near the fireplace just in case. An old sheet or tarp will take care of any unwanted mess.
Now that you have everything prepped, it’s time to get started. Remove your chimney cap if necessary, or any damper that blocks access to the chimney flue. Push the brush down through the chimney, scrubbing vigorously in small sections as you move down through the chimney.
As you get to the end of your first rod, attach another rod and keep moving down through the chimney. Repeat this process until you get to the bottom.
When the brush has reached the bottom of the chimney, begin working your way back up, pushing and pulling the brush, scrubbing vigorously to clean the inside of the chimney liner. Once you reach the top, begin going back down through the entire chimney again, until it is well scrubbed. It may take several passes. Be sure to wear safety glasses to avoid getting debris in your eyes as the brush comes out the top of the chimney.
Once you feel the chimney has been well scrubbed, take a flashlight and inspect it. Look down the chimney carefully to make sure there are no more deposits of creosote. If there are any deposits left, use the brush again to remove them.
After the chimney has been thoroughly cleaned, go inside to the fireplace and with a shop vacuum, carefully vacuum up the debris. Be sure furniture and carpets are covered to prevent soiling. Vacuum or sweep the fireplace box until it is nice and clean.
If you discover you have extensive creosote deposits that are not easily removed with a brush, you may need to hire a chimney sweep to remove them. Black, shiny creosote deposits called glaze creosote may need to be removed using specialized chemicals. Call your local chimney sweep for removal of stubborn glaze creosote buildup.
Thanks to Corey Binford for his step by step video on Chimney Cleaning 101. You can watch this video on YouTube.