Evaporated salts and minerals within curing concrete can produce white powdery deposits on basements floors. Efflorescence commonly occurs in newly built homes and structures exposed to high moisture levels. Although efflorescence is unsightly, it does not threaten concrete's structural integrity. Efflorescence often is only a temporary problem which resolves once concrete floors cure completely. However, the longer the white streaky stains remain on concrete, the harder they are to remove. Promptly remove efflorescence stains from a concrete basement floor using certain solutions and supplies.
Scrub the concrete floor with a wire brush to loosen the efflorescence. Remove as much white powdery residue as possible with the brush.
Inspect the concrete floor for stubborn efflorescence. If white stains remain on the concrete, put on long-sleeved clothing, rubber gloves and safety goggles. Open the windows to allow adequate air circulation.
Fill a plastic bucket with 2 gallons of warm water. Slowly pour 1/2 cup of the cleanser trisodium phosphate, or TSP, into the bucket. Thoroughly mix the solution with a paint stir stick.
Scrub the concrete floor with the trisodium phosphate solution using a nylon scrub brush. Thoroughly remove the remaining efflorescence from the concrete.
Fill another plastic bucket with warm water. Dampen a sponge in the water. Wipe the concrete floor with the damp sponge to rinse away the trisodium phosphate.
Wipe the concrete floor with a plush towel until thoroughly dry.
You can substitute muriatic acid for the trisodium phosphate. Carefully apply the muriatic acid solution as instructed on the product's label.
Use trisodium phosphate according to the manufacturer's instructions and precautions on the product's label to prevent safety hazards.