Efflorescence

Definition

The residue deposited on the surface of a material by the crystallization of soluble salts. A powdery deposit on the face of a structure of masonry or concrete, caused by the leaching of chemical salts by water migrating from within the structure to the surface.

Purpose

Efflorescence indicates the presence of soluble salts and moisture in masonry or concrete. While it is often a cosmetic issue, it can signal underlying moisture problems that need to be addressed to prevent structural damage and deterioration.

Examples of Use

• Observing white, powdery deposits on the surface of a brick wall after rain, indicating efflorescence.
• Identifying efflorescence on a concrete foundation, prompting investigation of possible water infiltration.
• Removing efflorescence from a masonry surface using appropriate cleaning methods to restore its appearance.

Related Terms

• Spalling: The breaking or flaking off of a surface layer, often due to freeze-thaw cycles or moisture infiltration.
• Hydrostatic Pressure: The pressure exerted by a fluid at equilibrium due to gravity, which can cause water to migrate through porous materials.
• Sealant: A material used to block the passage of fluids through the surface or joints of a structure.

Notes

• Efflorescence can often be removed with a dry brush or mild cleaning solution, but underlying moisture issues must be addressed to prevent recurrence.
• Proper waterproofing and drainage are essential to minimize the occurrence of efflorescence in masonry and concrete structures.