How to Clean Efflorescence from Bricks
You may have seen masonry bricks that have a buildup of white deposits on them. This is known as efflorescence. It is water-soluble salts that have been forced to the surface due to moisture penetrating the brick or grout. This phenomenon can happen to newly constructed brick surfaces or older existing bricks. The efflorescence can appear cloudy or milky white, green, brown, or yellow depending on the type of salts present in the brick.
Knowing how to clean efflorescence from bricks can be beneficial in the integrity and longevity of the brick structure. Efflorescence can be cleaned with a chemical cleaner commonly called efflorescence remover. In the case of a minor efflorescence problem, a mildly acidic soap solution may work well. A pressure washer can be used but may not be necessary.
In more severe cases of efflorescence where calcium and salt deposits have crystallized and built upon the surface, a calcite presoak may have to be used several times prior to using an efflorescence remover. Extreme care should be taken when using a pressure washer as to not damage the brick or mortar joints. Sandblasting can be used in extreme cases but can also leave the surface more porous which can lead to additional moisture problems if left untreated.
Knowing how to clean efflorescence from bricks will take care of the initial problem but will not cure it from happening again. Once clean, new salt deposits may begin to surface all over again. Considering that moisture penetrating the brick surface and acting with the salts is what causes the efflorescence problem the best way to prevent it from happening again is to apply a brick sealer.
Once the bricks are cleaned and allowed to completely dry, a brick sealer may be applied. Allowing the bricks to dry for several days after cleaning efflorescence is crucial. Applying a brick sealer too soon will trap moisture in the brick promoting efflorescence to reoccur. With the proper chemicals cleaning efflorescence from bricks can be easier and will increase the brick structure’s overall longevity and appearance.
Best Efflorescence Cleaners
If you have any questions on removing a failed sealer, please ask below
How can I remove efflorescence
I have a severe efforescence on my Cambridge pavers can I seal over supersealvoc?
or how should I proceed?
Remove the efflorescence first before sealing.