What Happens When You Go Too Long Without Cleaning Your Chimney

The Chimney Safety Institute of America (CSIA) recommends that homeowners using liquid and fossil fuel heating appliances clean their chimney at least once per year. Unfortunately, not all homeowners take the advice seriously, putting them at an increased risk of a fire and exposure to carbon monoxide. 

Fire Hazard

Many homeowners are not aware that there is a house fire somewhere in the U.S. every 87 seconds. It’s an alarming statistic. In 2018, fire departments across the country responded to nearly 387,000 residential structure fires, according to the National Fire Protection Association (NFPA) causing more than $8 billion in damages, an 8% increase from the previous year. Also, residential fires were responsible for 74 percent of all civilian injuries. An NFPA study found that the primary cause of residential fires was failure to clean the chimney. 

So, how can a dirty chimney cause such destruction? Lighting the gas or burning wood in the fireplace results in combustion. The process of combustion naturally creates several by-products including carbon monoxide, sulfur dioxide, and particulate matter, to name a few. When these chemicals mix inside the chimney it forms a substance called creosote. Creosote begins as a white powder that is very simple to sweep away. However, as you continue to light the fireplace without cleaning, it continues to accumulate in the chimney. Over time, the creosote becomes a hard, crusty, and tarry substance that clings to the flue and interior walls of the chimney. It is also highly flammable at this stage.  When the temperature inside the fireplace gets hot enough, or even a hot ember, it can ignite the creosote and start a fire in the chimney. A chimney fire can engulf an entire home in flames in less than 3 minutes.

Carbon Monoxide Exposure

Also, going too long without cleaning your chimney can also increase your exposure to carbon monoxide. This odorless, tasteless, and colorless gas is commonly known as the “silent killer” because it can strike without warning. More than 50,000 individuals are hospitalized and over 400 deaths occur each year due to carbon monoxide poisoning.  

When you go too long between chimney cleanings, residue from gases created during combustion build up in the flue. Also, small animals, pests, and debris can block the flue preventing dangerous gases from escaping through the chimney. Having nowhere else to go these fumes backup into your living space where they can cause serious harm. 

Respiratory Problems

A dirty chimney can cause other health problems too. The creosote and other contaminants that accumulate in the flue are irritants that can be toxic with prolonged exposure. If your chimney has gone too long without cleaning and is very dirty, you may develop flu-like symptoms. So, if you feel sick when inside the home, but feel better when you get outside, a dirty chimney may be the reason. Some of the symptoms include skin irritation, burning eyes, coughing, difficulty breathing headaches, and nausea. If you don’t clean the chimney and continue to breath in these pollutants, there is an increase risk of respiratory issues, lung cancer, and skin cancer.