How do you wash walls before painting?

To wash walls before painting, vacuum up dirty areas and use a cleaning solution consisting of trisodium phosphate. TSP is highly recommended by painting professionals for cleaning surfaces prior to painting.

1. Prepare the wall for washing

   Vacuum up dirty areas on or adhering to the wall, such as cobwebs or clumps of dust.

2. Wash the wall

   Mix TSP powder with warm water. Use eye protection and gloves to apply the TSP solution. Using a cloth, wipe down the walls with the TSP solution. Rinse surfaces with a damp, clean sponge. As TSP can darken some types of wood, use on wood only if desired.

3. Let the wall dry

   Wait for the wall to dry thoroughly before beginning painting.