Efflorescence is also known as calcium hydroxide or free lime. The phenomenon of efflorescence occurs when water soluble salts migrate to the surface of the paver with the help of water (i.e., condensation, rain).
Just as it appears naturally, efflorescence will eventual- ly disappear. Over time, rainwater can wash and wear it away.
Efflorescence occurs when water-soluble salts within concrete migrate to the surface and react with carbon dioxide to form calcium carbonate. This substance remains visible on the surface of the hardscape products like pavers, slabs and walls in the form of a white haze.
When the calcium hydroxide reaches the surface of the pavers, a chemical reaction occurs with the carbon dioxide in the air. As it reacts with the carbon dioxide, the calcium hydroxide forms a water insoluble calcium carbonate. The calcium carbonate creates the whitish haze on the surface of the concrete pavers.
When you install polymeric sand in the joints of pavers, the manufacturers suggest that you spray the paved area with water and leave time to dry. If you overwater the area their binders will leach out of the polymeric sand. It's this leaching causes that white haze, or polyhaze, on paving stones.
You can try cleaning the pavers with a mixture of water and mild detergent. Another option is to hire a power washing company to do a low-pressure wash. Other more aggressive options include sandblasting and a chemical cleaning. We always recommend you hire a professional to ensure you do not damage your pavers.
This form of efflorescence generally lasts around two to three years and fades naturally as the salt supply decreases. Salts are carried to the surface of concrete or brickwork by hydrostatic pressure or osmosis/evaporation, and deposited when the water evaporates, resulting in this type of efflorescence.
In many cases, efflorescence will disappear on its own over time (usually after the first year of a paver or retaining wall installation).
There's no single, definitive appearance - it is sometimes powdery, sometimes scummy: sometimes it's hazy and indistinct; sometimes it's sharp, crisp and obvious. Sometimes it covers large expanses or paving, sometimes it affects individual units, and sometimes it affects just half or two-thirds of a paving unit.
It is caused by water carrying salts to the surface, where they evaporate and leave behind the white residue. Efflorescence is not harmful to your pavers or travertine, but it can be unsightly. Sealing your pavers or travertine can help reduce the amount of efflorescence that forms.
Efflorescence is the white chalky powder that you might find on the surface of a concrete or brick wall. It can be a cosmetic issue, or it can be an indication of moisture intrusion that could lead to major structural and indoor air quality issues.
It is common for people to confuse mold with efflorescence. Efflorescence itself isn't dangerous or harmful. It can lead to potential moisture problems that can cause structural damage to building materials.
Unless something else is done, the efflorescence will be back soon. In order to prevent it, you'll need to: Eliminate soluble salts for your concrete or masonry, and/or. Prevent water from transporting soluble mineral salts to the surface.
Removing efflorescence can be quick and simple. In fact, efflorescing salts are water-soluble, which means efflorescence may disappear on its own due to normal weathering. Some of the best ways to remove efflorescence include: Pressurized water: Applying pressurized water may dissolve efflorescence quickly.
A few major differences between efflorescence and mold growth: Mold grows, efflorescence doesn't. Mold can grow on just about any surface, whereas efflorescence doesn't spread. Mold is a fungus, whereas efflorescence is moisture that evaporates into salt deposits.
Will rain wash away efflorescence? However, it's worth noting that rain alone may not completely eliminate the problem, especially if it is deeply embedded, or if the surface is not exposed to consistent rainfall. In such cases, additional cleaning methods or treatments may be necessary to address the issue.
Once the water source is eliminated, most efflorescence (also called Calcium Carbonate or limestone) can be removed with abrasive techniques. Dry brushing, light water blasting or light sandblasting followed by flushing with clean water. In large areas, rotary scrubbers with scrubbing pads may also be used.
Pressure washing can work to remove white efflorescence once the surface has thoroughly dried. The surface must be thoroughly rinsed to ensure that no residue remains. We also use a safe detergent to ensure a thorough clean.
The acidity in the vinegar helps remove the efflorescence and calcium deposits by breaking down mineral crystals. After cleaning the surface, let dry for 48-72 hours (moisture content below 25%).
Vinegar and water solution—Efflorescence can be removed by using a dilute solution of household white vinegar and water. A vinegar and water solution is relatively inexpensive, non-toxic, and easy to obtain, mix and apply. Dilution ratio is 20–50% vinegar in water by volume.
A cleaning service or a handyman may charge about $100 to remove efflorescence from the surface of a small area.
The acetic acid in vinegar is a little stronger than acid rain, so exposing your pavers to this substance can lead to bleaching, corrosion and the loss of protective sealant.
During the curing process, calcium hydroxide (in the form of moisture) comes to the surface and combines with carbon dioxide in the air. Together, those two elements create calcium carbonate, which is also known as efflorescence. In short, your paving stones aren't disintegrating; they're curing.