How to Get Rid of Efflorescence on Cinder Blocks
- 1). Remove light patches of water-soluble salt with a stiff brush and water. Use a mild detergent solution for rougher patches.
- 2). Mix baking soda and water in a plastic bucket -- stir the mixture while adding baking soda and continue adding it, until it begins to pile on the bottom of the bucket. Keep this bucket on hand during subsequent steps.
- 3). Put on rubber gloves and safety goggles. Mix a solution of 1 part muriatic acid and 12 parts of water in a plastic bucket -- add the acid to the water, not the water to the acid. Work in a ventilated place when handling muriatic acid of any concentration.
- 4). Flush any affected cinder blocks with water. Soak all exposed surfaces of the blocks including the insides, if they are accessible. Apply the muriatic acid solution to the cinder blocks with a brush. Allow the solution several minutes to breakdown the efflorescence.
- 5). Flush the cinder blocks thoroughly with water to remove the muriatic acid solution. Neutralize the remaining muriatic acid solution by carefully pouring it into the baking soda solution. Pour the baking soda solution down the drain -- once the acid is completely neutralized -- if the solution continues to fizz after adding the acid, then add additional baking soda until it stops.
- 6). Apply a penetrating waterproof sealant to all exposed surfaces of the cinder blocks to prevent further efflorescence. Follow the instructions for that particular sealant -- and do not use the cinder blocks until they are fully treated.