How to Clean White Efflorescence from Bricks and Concrete
Efflorescence is a white deposit of water soluble salts that can appear on masonry bricks. It can be a fine powdery substance or a crystallized buildup. Depending on the type of salts present it can also appear green, brown, or yellow. Efflorescence happens when soluble alkalis are present in the brick or grout and moisture is able to penetrate the brick forcing salt deposits to the surface. This can happen a month after the brick was laid or as long as a year later.
Before applying a concrete sealer or water repellent it is typically needed to prep the surface first. Prepping consists of cleaning with water and using a chemical cleaner that is specific to the stain you are trying to remove. Cleaners for concrete and brick pavers come in many different formulas.
Let’s look at the main reasons to clean and prep your concrete:
General Dirt and Grime Cleaning
When cleaning to remove dirt and grime you may just need water and a pressure washer. If the stains are stubborn, then a general all-purpose concrete cleaner or even bleach would help with the washing.