Brick efflorescence is a white crystalline substance which appears on red and brown brick work. It is a whitish, crusty looking coating that comes from the insides of the bricks. Brick efflorescence is mainly the result of a salt residue which is pushed from the inside of the brick to the outside surface.
What Does It Look Like?
Typically, efflorescence looks as though someone has taken a small paint roller, covered in white paint and roughly scored across the bricks with the paint. It does not coat and cover the entire bricks but appears ‘unfinished’. You will see many outdoor examples of this on brick walls, houses and garages, as well as other buildings which are constructed of brick.
What Causes Efflorescence?
The main cause of efflorescence is salt and water. When the bricks are made they will contain a certain level of water that was added to the mixture to bind it together, like a cake. If a brick has more than the adequate amount of water inside it, it will have more than the adequate amounts of salt too. The result is that the salty water gets dried out and pushed through the brick, to the surface. The salts have to have a pathway in which to travel to the surface and if a brick is constructed in such a fashion, the resulting appearance is efflorescence.