Painting basement walls can prove to be a challenging job, but following a few simple tips may help prevent some common mistakes. Adequate preparation is one of the most important areas overlooked when painting basement walls. Waterproofing treatments often work best when applied before the paint and primer. Applying two coats of good-quality primer will usually prevent stains from showing through the finished paint. Basements typically have poor ventilation, and care must be taken to properly vent fumes.
Professionally painting basement walls usually begins with a well-prepared surface. Unpainted concrete walls typically require more surface preparation than finished drywall. Begin by thoroughly cleaning the basement walls with soap, water, and chlorine bleach if necessary. Concrete walls should also be swept or vacuumed to remove loose mortar and dust. Any cracks or crevices must be repaired before applying a waterproofing treatment.
Some waterproofing treatments cannot be applied over paint so it is usually best to put them on first. Apply the treatment with a brush, long-nap roller, or sprayer according to the manufacturer’s directions. Remember to cover floors and furniture with a non-porous drop cloth during this procedure. Allow the treatment to dry completely between coats and before painting. Placing a portable fan in the room may help speed the drying process.
Painting basement walls typically requires the use of a good-quality primer. A stain blocking primer may be needed if water stains are present. At least two coats of primer should be applied for best results. A thick brush or log-nap roller typically works best on concrete block walls. Properly primed basement walls generally require less topcoat paint.
Basements located below ground level are typically damp and prone to condensation. A mildew resistant topcoat should always be used for painting basement walls. It is usually best to paint a border with a brush around fixtures, frames, and outlets and quickly fill in the broad areas with a roller. Two coats of paint are usually needed to produce the correct color. Concrete walls may be sponge-painted to hide surface imperfections.
Basements are typically windowless structures with poor fresh air ventilation. Precautions must be taken to prevent inhalation of dangerous fumes when painting basement walls. Placing a fan in the doorway will help supply fresh air to the basement. A ventilator-type face mask may also be needed when working with oil-based primers and paints. Remember to extinguish all pilot lights before using flammable mixtures.