How to Paint Cement Board

Step 1 – Clean the Area

First, clean the cement surface thoroughly that you want to paint. Skipping this step is one of the biggest mistakes DIYers make when wanting to paint cement board. To clean the cement-board surface, use a mild cleansing agent to remove grease and dirt buildup. You may also use cement-cleaning solutions to remove dirt and grime from the boards. Just make sure that you remove the solution completely before you start painting the cement boards.

Step 2 – Let the Area Dry

Before you paint the surface of the board, make sure it’s completely dry. Cement paint won’t adhere to a wet or damp surface. If you use any liquids to clean the cement board, wait at least two days before you paint it. Use plastic wrap to prevent moisture from settling on the surface of the board if need be.

Step 3 – Prime the Board

Warning: When using primer or paint, always wear safety gear, like gloves and a face mask. Avoid inhaling fumes for too long, and only work in well-ventilated areas.

To prevent cracks and bubbles in the future, you should prepare and prime your cement board. Use solvent cements with plastic resins to prime your board and soften it, so that the board adheres to the paint better. Follow the directions on your chosen primer. Ensure an even and smooth finish by using only high-quality cement primers. Let dry before painting.

Step 4 – Apply the Paint

Using a paintbrush or paint roller, apply the paint on the surface of the cement board. For best results, apply thin layers to the surface of the board, and let each layer dry before applying another one. Apply 3-4 layers of paint to ensure color stability and depth. Watch out for any bubbles and cracks on the surface of the board. If any bubbles or cracks occur, stop painting, strip the surface, and re-apply the cement primer.

Step 5 – Apply Sealant

After two days of drying time, you can apply paint sealer to the board. Apply the sealer based on the packaging’s directions. After adequate drying time, you're ready to install your cement board.

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