Trying to determine when to clean your chimney or how often cannot be based on a clean set of rules. You must check the buildup of creosote in your chimney to determine this. To do this use a fire poker, when there is no fire, to scrape the inside of the chimney walls. If you find that there is only a thin film buildup, your chimney does not need a cleaning at this time. However, if there is a buildup, then you should have it professional clean. If you find a buildup over ¼” do not use the fireplace until it is serviced. As an added note, please be sure to use proper eye protection and dust mask when do this type of self inspection.
When buying a home with a fireplace it is recommended that you have the chimney inspected prior to purchase. Your home inspector may be able to identify more obvious deficiencies with your chimney but only a CSIA Certified Chimney Sweep can perform a detailed inspection of a chimney. The CSIA (Chimney Safety Institute of America) recommends that any property being transferred that has a chimney have a level two inspection. A level one inspection examines readily accessible areas of the chimney whereas a level two inspection is more in-depth and can reveal hidden hazards.
I encourage you if you have questions about your chimney to visit the CSIA website at www.csia.org and read the homeowner resources.
