Chimney safety: How often do I need to have my chimney cleaned?

I took this photo during an inspection last week and it got me thinking about chimney safety. The black, tar-like substance covering this chimney cap is called creosote. Creosote is a byproduct of burning wood and is highly flammable. If not cleaned regularly, this sticky build-up could ignite, causing a chimney fire.

Most fire and chimney safety associations recommend yearly inspections and/or cleanings. A fireplace and chimney inspection will tell you how the components are functioning, and whether or not the build-up of creosote and soot warrant cleaning.

As a home inspector, I always recommend that my clients have their chimneys inspected and cleaned by a licensed chimney sweep before using their fireplaces for the first time. The reason is simple: you have no way of knowing how well the prior homeowners maintained the chimney nor how much wood was burned since the last cleaning.

After that, how much you burn should guide you as to how often you should have your chimney inspected. If you only burn once or twice a year, then you are probably safe waiting a couple of years for your next chimney inspection and cleaning. If you burn fairly often (as was probably the case with these homeownwers), then inspecting and cleaning yearly is more important.