What is efflorescence?

Hint: Efflorescence is something which is related to the properties of salt. We must have seen that a white or yellowish coating occurs on the surfaces of bricks, it contributes to efflorescence.

Complete Solution :
- Efflorescence is explained as a crystalline deposit of salts which will form when water is present in or on brick, concrete, stone, stucco or other building surfaces. it's a white or greyish tint and consists of salt deposits left behind when evaporation of water takes place. Additionally, efflorescence can appear as a powdery substance on floors and walls and requires special care to treat.
- Water, rain and snow are the main sources of moisture and may impact the degree of efflorescence. Degree of moisture generation is also affected by condensation, groundwater wicking and interior activities.

- There are some conditions must exist for efflorescence to occur:
i. Water-soluble salts must be present.
ii. Moisture must be available to convert salts into a soluble solution.
iii. Salts must have the properties to move through a material to its surface. The moisture will then evaporate and cause the salts to crystallize, leading to efflorescence.

- Various building surface installation problems also results in efflorescence, including:
i. Incorrect use of through-wall flashing
ii. Use of masonry without sufficient ventilation
iii. Use of masonry in areas that lack a correct moisture barrier
iv. Joint material failures
v. Improper ground storages
In chemistry, an example of efflorescence is when a gypsum is exposed to a dry environment it'll lose its water by evaporation and form a solid crust, anhydrite, on the surface.

Note: The best time for removing efflorescence is when the weather is warm and dry.
Stiff brush- On some smooth surfaces, you can use a stiff brush to remove.
Water rinse- On other surfaces, rinsing with a garden sprayer or pressure washer can dissolve efflorescence, allowing it to break out.
Chemical cleaning can also be used.