The reason high humidity can cause efflorescence, is because high humidity leads to condensation forming on the masonry surfaces. Condensation causes beads of moisture to form on the cool surfaces and is absorbed into the porous cement. Remedy For Excessive Humidity: Buy a good dehumidifier for your basement.
The truth is that a dehumidifier does nothing to counter or reverse the effects of efflorescence on your crawl space walls.
Efflorescence occurs when water soluble salts travel to the concrete surface. The mineral salts might be a result of the cement hydration reaction or can come from many other sources like sulphate rich sand. Porous concretes, masonry and mortars will be more susceptible to the migration of salts to the surface.
Using low alkali Portland cement can help reduce efflorescence. A well-graded aggregate, using a low water-to-concrete ratio, and preventing premature evaporation of water during curing are all good ways to reduce mineral salts. And finally, water sources used in construction should be clean, potable, and salt-free.
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.
A solution of baking soda (sodium bicarbonate) and water (Approx. 1 lb. Of baking soda per 5-gallons of water) can be used to neutralize the stain. The solution should be applied until it stops fizzing.
Most people confuse secondary efflorescence with mold because it looks like a white, dusty mold growing on your concrete. However, it is not mold but rather an indication of a water problem at hand—and where there is water, there is mold and potential structural damage.
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.
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.
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.
But if you wall has a high salt content, the efflorescence could develop again and again. The first thing to do is to take steps to keep water off of the wall as much as possible and see what happens. Consider a penetrating sealant that is specifically made to prevent efflorescence.
Efflorescence is often a seasonal problem, and humidity will impact whether soluble salts appear. It usually escalates in winter, since rain, snow, sleet and other inclement weather conditions may arise.
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%).
Efflorescence is minimum during humid conditions.
However, wall cracks, foundation cracks, pores in the concrete and even the floor-wall joint in your basement can create that entry point. When you see efflorescence, it means water is leaking into the area where you see it.
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.
Efflorescence alone does not pose a major problem, but it can be an indication of moisture intrusion, which may compromise the structural material. Building materials, such as concrete, wood, brick and stone, are porous materials. Porous materials can absorb or wick water by a process called capillary action.
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.
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.
By sealing with a penetrating concrete sealer, concrete is hardened up to 45% and efflorescence is eliminated. Since humidity can affect efflorescence, it has been shown that it can be a seasonal problem with efflorescence being most common during rainy seasons.
Unlike mold, efflorescence isn't normally harmful to human health, but it can cause mild irritation if inhaled or if it comes in contact with the eyes. Even so, efflorescence doesn't usually float freely in the air as dust. Pressurized water can dissolve efflorescence and clean away the mineral deposits.
Rain, humidity, condensation, groundwater wicking, and interior plumbing leaks are all potential sources of moisture that can cause efflorescence. As a result, it is often a seasonal problem, escalating when wet weather arrives in your area.
Differences Between Efflorescence & Mold
Mold is a fungus, efflorescence is moisture that evaporates into salt deposits. Efflorescence will turn into a powder when touched, while mold will not. Efflorescence is white, yellow or brown, while mold can be any color.
While efflorescence is a cosmetic issue that won't make you sick, it is a sign that something is going on with your moisture management. Leave it to linger a little longer and moisture will start manifesting in other ways.
Here's the deal with efflorescence and sealing … you do NOT want to seal before your pavers have had the chance to “breathe” and go through their normal efflorescence cycle. By sealing too soon, you'll run the risk of trapping migrating salts beneath the coating of sealer.