Case 1

Cause of Defects

Efflorescence can be summarized to be:

• The process where soluble salts in porous materials (bricks in particular) are deposited at or near the surface as a result of the evaporation of water that contains salts. Progressively, as the water evaporates, the salts crystallize out to form harmless superficial white deposits on the surface of the building.
• It has been described as usually being ‘a skin trouble and not a deep seated disease’.
• With the presence of sufficient water being introduced during construction or are applied to reduce suction, it carries these to the surface as the structure dries up, appearing as efflorescence after plastering.
• The water may also enter via a crackline located further up the wall travelling downward with its dissolved salts and exit at a weak point which most often is a crackline below.
• The presence of cracks in the plastering coupled by the capillary action of the water that carries the soluble salts from the cracks will results in streaks of efflorescence below the cracks (Figure 1a to 1c).