PREPARING A CONCRETE FLOOR BY ACID ETCHING

Source:www.stonediamondtool.com Date:2017/12/22 Read:574

Sweep the floor clean and dispose of dust. Remove from the floor any contaminant, including oil and grease. Dampen the floor and apply a 1:1 solution of muriatic acid and water through a sprinkling device. The acid should bubble vigorously when applied to the concrete. Coverage should be about 1 gallon of solution per 100 square feet. Allow reaction between solution and concrete to occur for approximately 3-5 minutes, then follow with a stiff broom or mechanical scrubber to remove surface laitance. Rinse the etched surface with clean water, preferably with a high pressure washer. If use of a pressure washer is not possible, rinse and remove water a minimum of three times to ensure a complete rinse is obtained. Do not let the acid dry out on the floor. Continue power scrubbing while rinsing with clean potable water.

Household ammonia or soda ash may be added in the rinse to help neutralize the acid. Pick up the water. Litmus paper should be used to check the pH of the rinse water. If the rinse water is not pH neutral (pH 7-8) or if there appears to be a film on the floor, additional rinsing is necessary. Allow the surface to completely dry then vacuum again to remove fine particles loosened by the acid-etch. Do not allow un-neutralized acid solution to flow into the sewer system or ground.