Can you apply epoxy grout over existing grout？

Can you apply epoxy grout over existing grout?

You can apply epoxy grout over existing grout, but it's essential to properly prepare the surface to ensure good adhesion and a satisfactory outcome. Here’s a step-by-step guide on how to do it:

1. Clean the Existing Grout: Ensure the existing grout lines are clean and free of any dirt, grease, soap residue, or mold. Use a grout cleaner and a stiff brush to scrub the grout lines thoroughly. Rinse with clean water and let it dry completely.

2. Surface Preparation: Once the grout lines are dry, lightly sand the surface of the existing grout with fine-grit sandpaper. This will roughen up the surface slightly, providing better adhesion for the new epoxy grout.

3. Remove Dust: After sanding, use a vacuum cleaner or a damp cloth to remove any dust or debris from the grout lines. The surface should be clean and dry before applying the epoxy grout.

4. Mix Epoxy Grout: Follow the manufacturer’s instructions to mix the epoxy grout properly. Epoxy grout typically comes in two parts (resin and hardener) that need to be mixed together.

5. Apply Epoxy Grout: Using a rubber float or a grout float, spread the mixed epoxy grout over the existing grout lines. Work in small sections to ensure even application.

6. Pack the Joints: Press the epoxy grout firmly into the grout lines to ensure good coverage and eliminate air pockets.

7. Clean Excess Grout: After applying the epoxy grout, use a damp sponge to clean off excess grout from the tiles. Rinse the sponge frequently in clean water to keep it from getting too dirty.

8. Final Cleaning: Once the epoxy grout starts to set (follow the manufacturer’s instructions for setting time), use a clean, damp sponge to lightly clean any remaining haze from the tiles.

9. Cure and Seal: Allow the epoxy grout to cure fully according to the manufacturer’s instructions. Epoxy grout typically requires a longer curing time compared to traditional cement-based grout. After curing, you may apply a grout sealer if recommended by the manufacturer.

By following these steps, you can effectively apply epoxy grout over existing grout lines. Proper surface preparation is crucial to ensure the new grout adheres well and provides a durable, attractive finish.