Painting Over Semigloss Without Primer

Mix 1/2 cup of ammonia with 1 gallon of warm water and use a rag to wipe the walls clean. Wipe the walls again with clean water and a rag.

Determine whether your paint is water-based or oil-based, if you are unsure which kind of paint you used last. Without priming you should not switch the type of paint you have on the wall, as it can result in a poor finish that may eventually crack and peel. Dampen a cotton ball with rubbing alcohol and rub a spot on the wall with it. If the color lifts onto the cotton ball, it's water based, or latex, and you'll need to use latex paint. If nothing comes off, it's oil based, or alkyd, and you'll need to use oil-based paint.

Get oil or latex paint in the same or similar color as you have on your wall. Changing colors without primer may require extra coats, especially if you're going from dark to light. It would end up taking more time, money and effort, so if you're not priming, it's best to stick with the shade already on the wall. You can choose any finish you want, though switching to flat or eggshell paints, which have more pigment, will give you better coverage than semigloss or glossy paint.

Cover your floor and furnishings with a drop cloth and protect moldings, adjacent walls or the ceiling with painter's tape.

Sand the walls, if desired. While not absolutely necessary, a light sanding with fine grit paper takes off the shine off the semigloss and gives a "tooth" to the wall for better adhesion. This reduces the number of coats you'll need, especially if you're using a semigloss or glossy finish paint. Wipe the walls well with a damp rag or tack cloth, and vacuum up the dust before painting.

Open your paint can and stir the paint thoroughly. Paint the edges and corners with a 2- to 3-inch paint brush.

Pour some paint into a roller pan. Roll on the paint to cover the remainder of the surface. Allow the first coat to dry, and examine the finish. Apply a second and third coat, if necessary, until you are satisfied with the coverage.