As of 2015, the average fee for a chimney sweep is between $100 and $250. Factors such as the amount of time since the last cleaning, the number of times the owner burns a fire each week, and the roof steepness also affect the cost.
Chimney sweeping is necessary because the smoke from burning wood leaves ash and carbon buildup on the chimney walls. Left in place, the carbon buildup increases the potential for flue fires, decreases the draw of the chimney, and increases the potential for carbon monoxide poisoning. If the owner does not employ a chimney sweep on a regular basis, the buildup solidifies and becomes much more difficult to remove.