Why are my red bricks turning white?

Why Red Brick Turns White: Understanding efflorescence November 1, 2012 Images courtesy Joseph Crissinger Efflorescence is one of the first signs of moisture problems for cementitious materials, especially masonry.

One of the next things we asked ourselves was, why is red brick turns white?

We can figure it out! it is the result of the combination of four factors: salt deposits;moisture;moisture path to the surface; andevaporation.

This begs the question “Why bricks turn white?”

Efflorescence is a crystalline deposit of salts that can form when water is present in or on brick, concrete, stone, stucco or other building surfaces. It has a white or greyish tint and consists of salt deposits left behind when water evaporates.

Softer than even the brick, mortar allows exterior water entry. While water sounds harmless, the truth is the water carries salts. Some comes from the ingredients inside the brick and travels outward, resulting in a white powdery substance often referred to as “construction bloom.” Other salts enter from the surrounding environment .

What are the causes of white mold on bricks?

White mold speciesAspergillus. Aspergillus is a genus composed of 100 different mold species from all different climates. Aspergillus usually has a wool or cotton texture. Penicillium usually appears in white and, other times, in pink or yellow hues and has a powdery texture. Cladosporium appears olive-gray and has a velvet texture.

White, powdery stains leaching from brick walls are actually crystalline salt deposits. Newly constructed brick walls often contain excessive moisture, which eventually evaporates and transfers salt deposits known as efflorescence onto brick surfaces.

Another popular question is “What causes efflorescence on brick walls?”.

In order for brick efflorescence to become a problem, your brick wall has to meet three conditions: First, your bricks or mortar have to contain water-soluble salts such as sodium sulfates (Na3SO4) or potassium sulfates (K2SO4). Second, water has to be able to get inside of the bricks and dissolve the salts.

A by-product of moisture combining with free salts, this phenomenon is not only just a cosmetic problem—left unchecked during freeze-thaw conditions, it can cause brick to weaken, spall, or crumble in some cases. Efflorescence caused by cold, damp weather.