Yes, you can put drywall mud over paint, but it's essential to prepare the painted surface properly to ensure good adhesion and a smooth finish. Here are the steps to follow:
Clean the Surface: Before applying drywall mud, clean the painted surface thoroughly. Remove any dirt, dust, grease, or contaminants that may hinder the adhesion of the mud.
Sand the Surface: Use sandpaper to lightly roughen the painted surface. This will help the drywall mud adhere better to the paint. Be sure to sand gently to avoid damaging the underlying paint layer.
Apply a Primer: After sanding, it's a good idea to apply a primer to the painted surface. A primer creates a suitable surface for the drywall mud to adhere to and promotes a more even finish.
Choose the Right Drywall Mud: There are different types of drywall mud available, such as all-purpose, lightweight, and setting compounds. Choose the one that suits your project needs. All-purpose mud is suitable for most repairs and finishing work.
Apply the Drywall Mud: Use a trowel to apply a thin layer of drywall mud over the painted surface. Start with a thin coat, and feather the edges to blend it with the surrounding area. Allow the first coat to dry before applying subsequent coats if needed.
Sand Between Coats: If multiple coats are necessary, lightly sand the dried mud between coats to achieve a smoother finish.
Finish and Texture: Once you're satisfied with the smoothness of the drywall mud, you can proceed with texturing, if desired. There are various texturing techniques you can use to match the existing wall texture.
Paint: After the drywall mud has dried and the desired texture is achieved, you can paint over the repaired area to match the surrounding wall.
It's worth mentioning that while you can apply drywall mud over paint, it is typically recommended to apply mud directly to the bare drywall surface for better adhesion and a more reliable finish. If possible, consider removing the paint from the area that needs repair before applying the drywall mud. However, if removing the paint is not feasible or practical, following the steps outlined above should help you achieve a satisfactory result.