What is Spalling?

Posted By Donna Hovey on 13.May.2014 in Brick Repair, Spalled Brick Repair

• Definition: Spalling is a result of water entering brick, concrete or natural stone and forcing the surface to peel, pop out or flake off. This is because there is moisture in the concrete. In basements, especially, moisture and often salt, too, pushes outward from the inside. Eventually, spalling can cause crumbling and destruction of a structure.Identifying Spalling
• Bricks with spalling have cracks and breaks in the surface and often large, crater- shaped chips. Other indications of spalling are loss of surface material and striations. Spalling often occurs in basements and around chimneys. If the damage is bad enough it may compromise the stability of the structure.
  

  What Are the Causes of Brick Spalling?

  Moisture Problems

  Moisture inside the bricks causes spalling. This occurs when the bricks are uncured or “green.” Under very hot temperatures the moisture turns to steam inside the bricks, thus causing it to expand and leave cracks, breaks or chipped areas.

  Extreme Heat

  Fire damage causes spalling to occur in bricks as well. The rapid expansion of the brick during a fire and the intense cooling effect of the water to extinguish the flames causes the bricks to crumble, crack and otherwise deteriorate.

  Prevention of Spalling

  The best way to avoid brick spalling is to eliminate the moisture. Buy the bricks from a reputable dealer that sells only cured quality bricks. Hire a chimney sweep or qualified professional to inspect your chimney cap. If the area around your chimney cap is cracked or the cap itself is defective, this allows water to seep into the brickwork below. Seal these areas around the chimney with a silicone waterproofing agent or masonry sealant to eliminate or reduce the moisture problem. Open mortar joints and cracks in the mortar also cause water to penetrate the bricks. Add fresh mortar or have the cracks repaired by a bricklayer.

  Repairing the Damaged Brick

  If only a few bricks are damaged by the spalling it is wise to simply ignore the cosmetic detriment. The only way to repair spalling is to take out and replace the affected bricks. This is a job for a restoration professional as the stability of the building or home may be compromised.  A professional will properly support the brick above and below the spalled brick to maintain structural integrity while replacing the brick and mortar joints.

  It is important at this time to discover what is causing any water damaged brick. Sometimes it is a failing eavestrough that has been leaking against the brickwork and causing further deterioration.  A situation like this would need to be addressed also to ensure it doesn’t continue on the newly replaced brick.