Back Button

The Best Way to Wash Walls Before You Paint Them

Lisa Jenkins

Preparing walls for painting may be a labor-intensive, seemingly unimportant chore, but washing your walls is part of proper preparation. The months, perhaps years, of collecting dust, smudges and even crayon marks needs to become a distant memory for your painting project to be successful.


To begin, wipe walls and baseboards with a dust mop as paint will not adhere well to dirty walls. Also grab four hand towels and at least two bath towels per wall, one bucket for rinsing and the other for your choice of cleaning solution.

Cleaning Solutions

A number of cleaning solutions are out there, and it really depends on the kind of grime on your walls and what kind of paint, flat or semi-gloss, is already there. Always test on an inconspicuous area of your wall first, especially if you are dealing with flat paint, to ensure the cleaner won't take the paint off or degrade the surface. If you have lived in a home free of children and animals, you don’t smoke and you generally take good care of your home, some dish soap and water should do the trick. If your children have created masterpieces on your walls, there are a few ways you can tackle the problem. Some crayon comes off easily with a soap and water solution, but you can also try a magic eraser or WD-40. If the walls have borne the brunt of cigarette smoke, you will want to use Tri-sodium Phosphate (TSP) to clean your walls. Sherman-Williams warns, that some products can “affect the overall finish on the existing surface and should only be used if you are planning to repaint the surface.” Others suggest a mixture of vinegar and water to remove the stains. TSP is also useful in places like a kitchen where dirt, food and grease stains the walls.


There are two schools of thought when it comes to washing your walls. Both suggest dusting from the top down but others disagree on the method of washing. A large group insists it is best to wash your walls from bottom to top, rationalizing that it is easier to clean a dirty streak on a clean wall than to further dirty up a wall. The other group says “why clean twice?” and suggests you wash from top to bottom. Once you have determined your course of washing action, place a bath towel at the baseboard to keep your floor dry. Dip one cloth in the bucket with cleaning solution. Clean a 1/4 to a 1/3 of the wall at a time, cleaning in circular motions. Dip another cloth inside the second bucket full of clear water for rinsing and rinse off the cleaned area. Promptly dry the area with a dry cloth. Wipe away any streaks as you go along.