What Kind of Paint for a Cement Bathtub Wall?

Preparation

• Remodeling a bathroom includes stripping the old foundation and installing new gypsum board or cement board, unless the wall is made of concrete (which contains cement). To paint a cement board or concrete bathtub wall, you must prepare the surface properly. Tape up the seams using standard wallboard tape and apply it with joint compound. For new cement surfaces such as these, trowel the surface with compound to even and smooth out the surface before painting it. Sand the wall smooth using fine sandpaper. It's now ready for priming. For solid concrete bathroom walls, these preparatory steps should be omitted and you can immediately move on to the priming stage.

Priming

• Existing cement wall with previous paint jobs should be sanded thoroughly to smooth out the surface and ready it for priming. For surfaces that previously had an oil-based finish, prime over the existing paint with a water-based latex primer. The same should be done with new, unpainted cement as well. Do not apply oil-based paints over water-based paint because they will not adhere. For a bathtub wall, you should use a water-based latex primer. Apply at least one coat, sanding between coats for a smooth surface.

Mildew Resistance

• Depending on your bathroom ventilation options, the room may collect a lot of moisture, which can lead to rot, mildew or mold. If you insist on not tiling the bathtub walls, it's important that you purchase water-based latex paints that have mildew-resistant properties. Most major paint manufacturers will sell paints marketed as bathroom paints. They are specially formulated to respond to humid environments, such as your bathroom, where mold and mildew are more likely to form.

Bath Paint

• A water-based paint is the best because the chemical properties create a waterproof layering as well that also helps block the growth of mold and mildew; it runs off the surface instead of saturating it. Apply the paint to the surface in the same fashion as with other paint jobs. Tape off the area with masking tape to prevent paint overflow. Use a short nap roller to apply the paint and use a paintbrush in the corners. Apply at least two coats, allowing an adequate enough drying time between them.