If you’ve ever noticed a white chalky substance appearing on masonry, you’re likely looking at efflorescence. It’s a common occurrence and can appear on both new and existing buildings. While efflorescence can be frustrating—especially when you’re trying to maintain the appearance of your masonry—it’s important to understand what causes it, what it means, and how it should be addressed before applying a Stayntech® masonry stain or other finish.
Efflorescence is a crystalline or powdery deposit of water-soluble salts that forms on the surface of brick. Salts can be found naturally in brick as well as come from surrounding soil, water, or other materials that come in contact with masonry. When moisture moves through brick, it can dissolve the salts and carry them toward the surface. Once the water reaches the surface and evaporates, the moisture disappears—but the salts remain behind.
What Causes Efflorescence?
Three basic ingredients are generally needed for efflorescence to occur: Soluble salts + water + a path to the surface.
If one of these elements is eliminated, efflorescence cannot develop. Moisture is often the key factor. Water may enter masonry through rain, irrigation, leaks, improperly sealed joints, flashing problems, groundwater, or simply the moisture present during new construction. Because brick is naturally porous, moisture can move through its microscopic pores. As it travels, the water can pick up soluble salts and transport them to the surface.
Is Efflorescence a Sign of a Serious Problem?
Not necessarily. Efflorescence itself is usually an appearance issue rather than structural damage. It is particularly common in newer masonry construction because significant moisture can be present in brick, block, mortar, and other building materials. As the masonry dries, salts may migrate to the surface. However, persistent or recurring efflorescence can sometimes indicate that excessive moisture is entering the masonry.
If efflorescence repeatedly returns after cleaning, it’s worth investigating the source of the moisture rather than simply continuing to clean the surface. Possible sources include leaking gutters, damaged flashing, cracks, failed sealants, poor drainage, irrigation hitting the wall, or water entering from behind the masonry.
Primary vs. Secondary Efflorescence
Efflorescence is often divided into two general categories. Primary efflorescence typically occurs during the initial curing or drying of masonry. Moisture already present in the materials moves toward the surface and leaves salts behind as it evaporates. This is common with relatively new construction and may diminish as the masonry dries. Secondary efflorescence occurs later and is usually associated with moisture entering an existing masonry assembly. When secondary efflorescence continues to return, identifying where the water is coming from becomes especially important.
How Do You Remove Efflorescence?
Light efflorescence can sometimes be removed with a dry, stiff-bristle brush. In other situations, additional cleaning may be necessary. The correct cleaning method depends on the masonry material, the severity of the deposits, and the source of the salts. Always use cleaning products and procedures that are appropriate for the specific masonry surface.
Aggressive cleaning methods can potentially damage brick faces, mortar joints, or surrounding materials. Just as importantly, cleaning the visible salts doesn't necessarily solve the underlying problem. If moisture continues to move through the masonry, efflorescence may return.
Efflorescence and Stayntech® Masonry Stain
Before staining your masonry, make sure the surface is clean and free of efflorescence and investigate any ongoing source of excessive moisture. It’s also important to determine whether an ongoing moisture problem is causing the efflorescence. Proper preparation helps create a better environment for the stain to penetrate and perform as intended. Applying Stayntech® without addressing excessive moisture doesn't eliminate the source of the salts.
To purchase Stayntech® masonry stain, or to request a commercial masonry staining estimate, please visit stayntech.com.