What does efflorescence refer to in construction?

Efflorescence refers specifically to the whitish mineral deposits that can form on the surface of foundation walls, bricks, or masonry. This phenomenon occurs when moisture within the material evaporates, leaving behind soluble salts that crystallize on the surface as water escapes. The presence of efflorescence is often an indicator of moisture issues in construction materials and can suggest the need for better drainage or waterproofing solutions.

The other options describe different aspects of construction but do not accurately represent the phenomenon of efflorescence. For example, insulation refers to materials that help in energy conservation by reducing heat transfer, while a decorative masonry finish pertains to aesthetic treatments applied to surfaces. The method of waterproofing involves techniques and materials specifically designed to prevent water ingress, which is related but distinct from the effects of efflorescence. Understanding efflorescence is crucial for addressing potential moisture problems in building structures.