How to Acid Etch Concrete

Acid etching is a process used to prepare concrete surfaces for painting, staining, or other decorative treatments. It involves the application of an acid solution to the surface of the concrete to create a rougher texture that helps the coating to adhere better. Here are the steps to follow for acid etching concrete:

1. Clean the surface: Before you begin acid etching, make sure the surface is clean and free of any dirt, debris, or other contaminants. You can use a pressure washer or a strong detergent solution to clean the concrete thoroughly. Allow the surface to dry completely before proceeding.

2. Choose the right acid: The most commonly used acid for concrete etching is muriatic acid, also known as hydrochloric acid. You can find this acid at most hardware or home improvement stores. Be sure to read the label carefully and follow all safety precautions.

3. Prepare the acid solution: Mix the acid with water in a plastic bucket or container, following the instructions on the label. It's important to add the acid to the water, not the other way around, to avoid dangerous splashing or spattering. Use a plastic stirrer to mix the solution thoroughly.

4. Apply the acid solution: Using a plastic watering can or a sprayer, apply the acid solution to the concrete surface. Be sure to wear protective gloves, eye goggles, and a respirator to avoid contact with the acid fumes. Start at the far end of the concrete surface and work your way back toward the exit to avoid stepping on the wet acid.

5. Scrub the surface: After applying the acid solution, use a stiff-bristled brush to scrub the surface of the concrete. This will help to remove any remaining debris and ensure that the acid penetrates the surface. Rinse the surface thoroughly with clean water and allow it to dry completely.

6. Neutralize the acid: Once the surface is dry, neutralize the acid with a solution of baking soda and water. Mix about one pound of baking soda with a gallon of water and apply it to the concrete surface with a plastic watering can or sprayer. This will help to neutralize any remaining acid and prevent it from damaging the coating.

7. Rinse the surface again: After neutralizing the acid, rinse the surface thoroughly with clean water. Use a wet vacuum or mop to remove any excess water and allow the surface to dry completely before applying any coatings.

It's important to follow all safety precautions when working with acid, including wearing protective gear, working in a well-ventilated area, and disposing of the acid solution properly. Acid etching can be a messy and time-consuming process, but it's essential for achieving a smooth, even coating on your concrete surface.