Have you ever noticed a chalky white powder on the walls of your building? No, it’s nothing nefarious. You’re seeing efflorescence, an issue that is common with any type of masonry.

This substance is the result of moisture reacting with minerals in the masonry. Moisture moves through the porous masonry and leaves deposits on the surface. Efflorescence isn’t dangerous, but it is unsightly, and you may not want to leave it on your building’s exterior.

What is efflorescence?

Salts and other minerals are found in concrete and many other types of masonry. Under the right conditions, water carries these minerals to the surface where they spread out in the form of a powdery white substance. For example, lime in Portland cement is carried to the surface and combines with carbon dioxide.

What are the right conditions? Humidity plays a big role in efflorescence. In less humid environments, the water that carries minerals to the masonry’s surface evaporates before it reaches the surface. In humid environments, water can more easily flow to the surface.

Sometimes efflorescence can happen very quickly after the masonry is installed, and other times it can happen gradually. This can depend on the type of masonry. More density in a material makes it difficult for migration of these minerals to happen.

The good news is that efflorescence doesn’t last forever. After several years, all the minerals are carried out of the masonry, and you shouldn’t notice it again. But until that point, it’s important to clean your masonry surfaces.

This problem can be prevented early on either by adding a hydrophobic agent to the masonry or by ensuring that bricks aren’t exposed to moisture before construction.

Cleaning efflorescence

Simply hosing down the side of your building isn’t necessarily going to get rid of efflorescence. In some cases, the water-soluble salts will migrate back into the surface and then re-appear when the masonry is dried. In other cases, an acid may be required for removal. Since using chemicals may also damage some masonry surfaces, this is something best left to professionals.

Efflorescence removal is one of several building cleaning services offered by JK Industries. If you notice this or any other blemishes such as rust staining, contact us to remedy the issue.

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