What Is a Spalled Area?

Spalling is a term used to describe areas of concrete which have cracked and delaminated from the substrate. There are a number of reasons why spalling occurs including freeze thaw cycling, the expansive effects of Alkali Silica Reaction or exposure to fire.

What does spalling mean in construction?

Spalling is the flaking or peeling away of small particles of cement paste from the near-surface portion of the finished slab. In most instances, the defect does not affect the slab's service life if untreated. Freezing and thawing cycles can cause concrete to spall.

What does spalling look like?

Spalling concrete can look like round or oval depressions along surfaces or joints. Spalling tends to be most common in cold climates when de-icing chemicals are applied or when seasonal freeze-thaw cycles damage the concrete.