How to Clean White Brick Exterior With Muriatic Acid
- 1). Prepare the area for cleaning. Dampen the wall with water. Lay protective fabric and dampen plants with water to avoid acid coming in contact with items other than the brick. Do not spray the acid if there is a significant wind; use a brush instead.
- 2). Mix the muriatic acid with water. Always pour the acid into the water and pour slowly, as this will help to avoid splashing of acid. Typically, the mix is 1 part acid to 10 parts water. Follow the manufacturer's instructions on mixing ratios.
- 3). Brush or spray the acid onto the wall. If spaying, use a plastic sprayer. Intend on throwing the sprayer away after use and have multiples in case you do not work fast enough. The sprayer will eventually be destroyed by the acid.
- 4). Let the acid sit for no more than a few minutes before cleaning off. When you see the reaction occurring, begin rinsing with water and scrub the wall with a stiff bristle brush. To remove any remaining acid, mix 1 cup of ammonia to 1 gallon of water to neutralize any acid still on the wall.
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