What is Efflorescence?

White minerals blooming on the surface of bricks and concrete are known as efflorescence. These deposits often appear without warning on freshly laid concrete and brick.

Efflorescence begins as a white dusting on masonry surfaces. Left unchecked, this blight can grow into crystalline structures resembling plants or fine hairs. Fuzzy white deposits are frequently mistaken for white mold, and while both create similar eyesores on masonry, efflorescence is not a danger to public health like mold is.

The blooming white substance is actually a mineral formation created by water evaporating from masonry, and it can be removed and treated by a specialist in basement repairs and renovations.

What Causes Efflorescence in a Basement?

Efflorescence forms on basement walls and floors because moisture is traveling through them, and is carrying dissolved minerals to the surface. Brick and cement are porous, so some moisture is naturally moving through them at all times unless special sealants are applied.

The masonry used to build basement walls and floors contains natural minerals like clay and limestone. As with all natural materials, there are often some harmless inclusions blended in with concrete or brick before they set. Some of these inclusions can break down with water, and travel to the surface of the brick or concrete as water evaporates.

Salts like calcium carbonate are the most common causes of white efflorescence in basement concrete. In coastal areas, moist salty air and rain can accelerate the formation of efflorescence. In the winter, rocksalt can mix with melting snow and ice to work its way into the foundation of homes, especially those with poor drainage.  

How to Prevent Efflorescence in a Basement

The best way to prevent efflorescence in basement concrete is to have the surface professionally sealed. There are a variety of coatings with different price points and roles to fill.

  • Acrylic sealers are a lightweight option. They work best on decorative concrete and surfaces that won’t see much wear, but won’t hold up to heavy foot traffic. Acrylic is like a topcoat, resting on top of the finished concrete.
  • Epoxy sealers are often the preferred finishing coat for concrete. Their durability far surpasses the abilities of acrylic sealers.
  • Penetrating sealers use a chemical formula that fills the pores in the concrete rather than building a barrier across the surface. There are a variety of high-performance penetrating sealers using different chemical make-ups. Penetrating sealers won’t keep the top surface as blemish-free as epoxy, but their performance in moisture and chemical resistance is far superior.

How to Fix Efflorescence in Basements

If your basement walls are unsealed and efflorescence appears, rest easy knowing that effloresce can be removed. The deposits become harder to remove the longer they’re allowed to rest on the masonry, so it is best to clean the surface as soon as possible. Here are some of the ways efflorescence can be removed:


  • Scrub brush and detergent: For minor cases, simply scrubbing the salts away with a household detergent can be enough to remove them. Hitting the spot with hot water will make it seem to vanish, but as soon as the water dries it will just reappear. Be sure to use a good detergent soap and lots of elbow grease when trying this approach.


  • Pressure Washer: Stubborn efflorescence that won’t go away with a good scrubbing might respond to power-washing. This should never be done on any interior walls, but can be a useful approach for places like the aboveground portion of a foundation wall suffering efflorescence.
  • Chemical Treatments: For severe and persistent efflorescence, it will often take a professional to renew the concrete’s surface. A wide variety of chemical treatments exist to treat efflorescence, including acids that etch the surface and a variety of less-dangerous chemicals designed specifically for the purpose.



Please do not attempt to use acid treatments on your own. They are available at many retail construction supply stores, and it might be tempting to avoid paying a professional to apply them. Acids require a full respirator and special clothing to safely handle, and a must be safely neutralized once applied. These chemicals can melt the skin from your bones and the fumes can kill you if handled improperly. Your life is worth more than a clean basement wall.

Should I be concerned about efflorescence in basement concrete?

Yes, because efflorescence is a sign that something is wrong with your basement’s moisture management. By itself, efflorescence is just a cosmetic issue. White mineral splotches on the concrete don’t cause structural damage and they don’t make people sick, but they’re evidence that something is going wrong behind the surface.

Does efflorescence mean that you have a leaky basement wall?

It definitely could. You’ll need a contractor who handles basement repairs to assess the problem. Foundation cracks or poor drainage could be causing a lot of moisture movement in your concrete and raising the chances of structural water damage.

Minerals working their way to the surface of brick or concrete are a natural phenomenon, so a little spot of efflorescence probably isn’t a leaking foundation. Properly sealed walls shouldn’t look like they were spray-painted white, and severe efflorescence is probably a result of water leaking in somewhere. It could be a basement wall issue, or it could be another poor drainage issue like gutters or a leaking sprinkler line. Your contractor should be able to determine the issue and find a solution to keep your basement efflorescence free.

Finishing a Basement With Efflorescence

Efflorescence should not stop you from finishing a basement. A contractor should remove severe deposits and properly seal any concrete before moving forward with a basement remodeling. The problem should never be ignored, since moisture can easily ruin a newly finished basement.

Once the efflorescence is removed and the surface is treated, there should be no problem framing walls and installing flooring.

Does Your Basement Have Efflorescence?

If you want professional help to assess and treat mineral bloom on your basement walls, call Dry Basement Solutions at 609-647-4555 for a consultation. With over 25 years of experience, this local family-run company is ready to help with your basement repair and remodeling needs.