Efflorescence is removed by natural weathering processes - as rainwater is slightly acidic, it gradually dissolves and washes away the deposits. The process may also be assisted by warm dry weather when the deposit is blown away.
Myth #2: “Efflorescence will always go away on its own.”
If efflorescence occurs only once on new construction (in what some refer to as “new building bloom” when a structure goes through its first conditioning cycle), there's a good chance efflorescence will go away on its own over time as rain sheds the stain away.
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.
No-one can say how long any incidence of efflorescence will last. It might be a few weeks; it might be a couple or three months; it &could be a year or two. There are so many factors affecting its generation and appearance, and its disappearance that an educated guess is the best we can manage.
Clear water repellents, silicone and acrylic coatings also may help you remove efflorescence as well. The coating will absorb water across a masonry surface and prevent efflorescence from recurring. Plus, the combination of warm water and white wine vinegar has been shown to eliminate efflorescence.
Efflorescence must be removed before applying a penetrating sealer.
You can remove the chalky buildup with a stiff brush, but the only way to get rid of efflorescence for good is to remove the source of the water. To do that, you need to talk to a basement waterproofing expert from JES, who will address your concerns at the root.
Despite the appearance of stains or marks on the surface, it's important to note that efflorescence will not compromise the strength or durability of your concrete pavers. Its impact is solely aesthetic and temporary in nature.
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%).
We were told a diluted CLR solution would work. We tried this and it was a lot of work to scrub the surface clean of the residue and you have to be sure to rinse immediately because technically CLR is not for painted surfaces.
Efflorescence itself isn't dangerous or harmful. It can lead to potential moisture problems that can cause structural damage to building materials. So it is important to take action when you notice efflorescence in your basement, on your paving stones, or on other structures.
Power Washing
We get this question a lot: “Can't we just power wash it?” Yes, you can certainly try. However, spraying efflorescent deposits with a power washer is the least effective way to remove the white stains from your brick and mortar.
Painted surfaces already damaged by efflorescence must NOT be repainted until the source of the moisture is identified and eliminated or blocked (by waterproofing). It may be necessary to engage the services of a qualified waterproofing specialist.
To remove the efflorescence, I suggest using Crommelin 4L Efflorescence Remover in combination with a stiff bristle brush. Please make sure to follow application instructions and allowing the product to activate first. If washed or removed too early the product will not work properly.
The Extent of the Issue: A small amount of efflorescence might not be a deal-breaker, but extensive or recurring efflorescence could indicate significant moisture problems.
The primary source of moisture for the occurrence of efflorescence is rainwater that penetrates or comes in contact with masonry. Rainwater will penetrate all masonry walls to some degree, more so if they are improperly designed or detailed.
You will still use hydrochloric acid to eat away the efflorescence however because the tile is super porous you need to be mindful to ensure that surface is sufficiently wet not just before you apply the acid but during the application as stone and concrete will start absorbing the water initially applied which will ...
Efflorescence can generally be expected to disappear over time, depending on the environment where the paving or brickwork is on a project. However, rainwater, being slightly acidic, can dissolve the surface deposit.
I attack the more tenacious efflorescence with a grinder wheel first, get the surface area as low as I can, then wet the area with water and squirt the acid directly over the efflorescence , rinse off and sometimes repeat the process .
In all but very extreme cases, efflorescence will stop as capillaries in the stone become blocked by crystallized salts. Once the process stops, the white deposits will eventually wear off with use and exposure.
A stiff scrubbing brush and a dry brushing technique will remove the efflorescence. Muriatic acid can be used for efflorescence removal, but it poses risks such as discolouration and potential surface damage. Consider safer commercial solutions.
Using a water-dampened sponge or garden hose, wet the area to be cleaned. Apply the cleaner and etcher solution to the area with a sponge or pump sprayer. Using a scrub brush, lightly scrub the area to remove the white powdery residue from the surface.
Efflorescence on pavers will eventually stop on its own after the salts in the pavers have dissipated. On the other hand, recurring efflorescence may indicate an ongoing problem of water intrusion that needs to be addressed before it causes permanent damage to the structure.
Costs range from $150 to $850 for efflorescence repair.
If you see a white powdery substance (as you will see below), it is natural salts present in the masonry and is the biggest enemy of any waterproofing job. The white powdery substance is efflorescence, and you want to neutralize it with DRYLOK Etch which is much safer than muriatic acid.