Spalling is the name used to describe chimney bricks that have begun to chip, loosen or otherwise decay. A chimney full of spalling bricks can be an eyesore, but more importantly, it can be a dangerous structure to use and live around.
Why your chimney has spalling bricks
A variety of events can cause bricks to start decaying. Here are some of the most common:
Old age: Like just about everything, chimney bricks and the mortar that connects them have lifespans. Older bricks are more likely to decay simply because of old age as well as due to the causes listed below.
Water damage: Water and bricks don’t mix. Water erodes bricks, and if there are cracks in the chimney masonry, water can seep in and expand when the air temperature drops below freezing. Significant damage often is the result. Unfortunately, there aren’t many ways to keep water and melting snow off the bricks of your chimney.
Non-breathable waterproof sealant: Waterproofing, when done correctly, is about the only way to keep bricks safe from external water damage. But make sure a breathable sealant is used, otherwise the moisture that gets trapped between the coating and the bricks will cause the very problem you’re trying to avoid.
Lightning strikes: Needless to say, a good lightning strike can cause brick spalling within your chimney structure.
House-settling: The normal settling that houses do over the years can cause cracking in chimney bricks and mortar, particularly if the chimney was built incorrectly.
Cheap bricks and mortar: Part of incorrect chimney-building is using inferior bricks and mortar compounds. Salvaged bricks, for example, are notorious for having shorter lifespans and suffering damage earlier than high-quality bricks.
The danger homeowners face with a damaged chimney
Chimney masonry damage can lead to all kinds of unwanted scenarios. Most often, spalling bricks will allow water into the chimney system where it will cause further compromise as well as possible damage to the chimney liner, fireplace damper and adjacent areas of the home such as ceilings, walls and beams.
It’s common for much of this water damage to go unnoticed until a serious health or safety risk occurs. This is especially true with mold outbreaks behind walls and in attics that remain shut up most of the time. Beyond repairable structural damage to the chimney and its components and the house itself, brick spalling can lead to a collapsed chimney. When this happens, parts of the roof and items in the yard beneath the chimney can be destroyed. People and pets can be seriously injured during a chimney collapse.
How to solve a brick-spalling problem
As dire as the results of ignoring spalling bricks can be, solving the problem usually isn’t difficult. The idea is to catch it early. This is accomplished by your own periodic inspections of the chimney’s exterior as well as yearly scheduled chimney inspections by a certified chimney professional.
Chimney repair work often recommended for spalling bricks includes:
Waterproofing with a breathable sealant
Tuck-pointing to replace missing areas of masonry with strong, new mortar
Partial or complete chimney rebuilding to restore safety and performance to the structure
Repair or replacement of components damaged as a result of brick spalling including the chimney cap and crown, chimney liner, roof flashing, damper, firebox bricks and more
Do you have some brick spalling going on with your chimney? Fluesbrothers Chimney & Fireplace of Kansas City, KS, is ready to help. Our certified chimney repair experts can address spalling brick issues and any collateral damage and make your chimney safe again. Call us today at (913) 236-7141.