A discoloration, generally white in color, may develop on your stucco, brick or stacked stone surfaces. This is known as efflorescence, and is basically just salt that is deposited on the surface through a natural chemical process. Although efflorescence changes the appearance of the surface, it is not structurally damaging or harmful to the masonry.
To remove efflorescence, mix warm water with a bit of vinegar, then scrub the area with a stiff brush. If this does not work, you can purchase special cleaning products from your local hardware store. Make sure to check the manufacturer's product information to ensure that you do not use any harmful substances on these surfaces, as damage will not be covered by warranty.
Staining may also occur on exterior surfaces as a result of dirt that is splashed up when water hits the ground. If you notice this type of staining, we suggest hiring a professional company to clean it. Installing gutters can help prevent a future occurrence, as gutters direct rainwater to specific locations.
Besides efflorescence and staining, mold can also form on your exterior surfaces. Minor occurrences of mold should be cleaned using products designed specifically for cleaning mold. After you've cleaned your exterior surfaces, you may notice a slight variation in color. Before you use any product on your home, you should always test it in an inconspicuous spot to ensure that there will not be any significant change to the finish. Also, before beginning any touch-up project, make sure that you are prepared to refinish the entire area for uniformity if it becomes necessary.
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