Identifying Chimney Discoloration
Unattractive discoloration on your chimney isn’t just an eyesore. It may be the symptom of a serious chimney issue. If it is, you will need to address the underlying problem to restore your chimney. Ignoring the root cause could lead to expensive repairs or dangerous risks. Different issues cause different types of discoloration. We have put together this guide on the most common types of chimney discoloration and their causes for you.
Green or Blueish Stains
Green, blueish and even some black stains are a sign that your chimney has a mold or algae problem. You could suffer from increased allergy symptoms and other more sever health problems if they continue to thrive in your chimney.
Mold and algae thrive in damp, dark places. If either one is growing in your chimney, it is an indicator that your chimney has a moisture problem. A missing chimney cap, cracked crown or damaged flashing may be the source of the problem. Hiring a professional chimney technician to inspect your chimney is the best way to find out how water is getting into your chimney. Solving the underlying problem will prevent the mold and algae from growing back once it is removed.
White stains are also an indicator of moisture problems in your chimney system. These stains are known as efflorescence. They are caused by salt deposits in the brick and mortar that are pulled out as water evaporates from the masonry. Waterproofing the masonry with a sealant approved for chimneys may be the solution. Untreated masonry acts like a sponge absorbing water. When the water it has absorbed freezes and thaws during the winter, it can cause cracks and breaks. Overtime, this can destroy the structural integrity of your chimney.
If you notice that the bricks in your fireplace look damp, the effloresce may be caused by a chimney leak instead of untreated masonry. In that case, your chimney should be inspected by a certified chimney sweep to identify the source of the leak.
Red or Reddish-Brown Stains
Red or reddish-brown discoloration is usually caused by rust. Most likely, rust from a metal chimney cap or chase cover that is corroding. It is a sign that it needs to be replaced. A rusted cap can quickly develop holes that allow rain, sleet and snow into your chimney system. Installing a new chimney cap is an inexpensive solution to protect your home from water damage.
Black or Brown Stains
Black and brown discoloration could be a sign of mold or rust, but it is most likely staining from creosote or soot. Creosote is a highly flammable chemical compound created by burning fuel like firewood. It is the leading cause of chimney fires. If there is enough creosote in your chimney to cause discoloration, your home is at greater risk of a house fire.
If you have a gas fireplace, then the discoloration is from soot not creosote. It is most likely an indicator that your fireplace is overproducing carbon monoxide which means you may be at greater risk of CO poisoning.
Both soot and creosote stains are due to serious hazards. It is smart to contact a trusted chimney sweep immediately to clean or inspect your chimney.
Give us a call if your chimney is discolored! The experienced chimney sweeps on our team at Burlington Fireplace and Heating are here to help. We serve residents throughout Southeast Wisconsin.