Most chimney bricks are some shade of red. As years pass and the chimney is used more and more, other colors can show up in the form of stains on your exterior masonry. Fluesbrothers Chimney & Fireplace of Kansas City, KS, would like to present an overview of four of the most common types of chimney stains. We’ll talk about why they’re on your chimney and what should be done about them.
1. White chimney stains
White stains, called “efflorescence,” are pretty common. They can be caused by the normal evaporation of rain and snow. They can also be caused by salts that are leached out of the chimney bricks by incoming moisture. The stains themselves won’t harm the chimney, but the water penetrating the bricks can.
How to address this problem: A chimney inspection will determine if enough water has entered the bricks to damage them. Damaged bricks can be replaced. After repair work is done, a waterproof sealant can be applied to protect the masonry from future water damage.
2. Various green, blue or black chimney stains
Typically, these stains are caused by mold or algae. Both substances grow well in damp, poorly ventilated areas, including cracked sections or gaps in a chimney’s bricks and mortar.
How to address this problem: Mold and algae can be cleaned off with a cleanser designed for this purpose. If there are cracked bricks or decayed mortar, these problems can be repaired. A masonry sealant can then be applied.
3. Brown and black (non-mold) chimney stains
These stains usually indicate that creosote and soot are escaping the chimney flue and washing down the structure’s exterior. You may see brownish or blackish stains on the chimney masonry as well as on the roof. Chimney fires, which most often are the result of ignited creosote and aren’t always noticed by people in the home, can lead to this kind of staining.
How to address this problem: An inspection will find out why the stains have formed. Your chimney technician will repair any damage and perform a thorough chimney sweeping to remove creosote and soot from your flue. He or she will consult with you on ways to reduce the chance of future chimney fires.
4. Rusty chimney stains
Rust forms on certain metals, not on bricks. If you have rusty stains on your chimney masonry, it’s likely that the chimney cap, flue cover or chimney chase top is the source. Water and melting snow send the rust down across the masonry.
How to address this problem: Galvanized steel components at the top of chimneys often rust out after years of use. If your chimney cap or chase top has fallen victim to rust, your chimney technician will replace the component with one that’s less susceptible to rust damage.
Call Your Kansas City chimney experts
Fluesbrothers is standing by to help with any chimney stain issues you’re experiencing. We provide certified chimney sweeping, licensed chimney inspections and repair and rebuilding work for all types of chimney systems. We also provide the advice you need to keep your chimney safe and strong all year long.
Reach a chimney expert today at (913) 236-7141. You can also get in touch with our simple contact form.