To Strip or Not to Strip: Painting over wallpaper.

Ask a room full of people and some will say, “Paint over the wallpaper. I’ve done it lots of times.” Others will say, “Painting over wallpaper is asking for a disaster.”

Both thoughts are correct. It depends on the condition of the wallpaper, the type of wallpaper, the prep of the wall before the paper was hung, and the prep you are willing to do before you paint.

If you paint over wallpaper that is already peeling along the seams or has bubbles, the weight and moisture of the paint will cause the seams to curl further and the bubbles to become bigger. Flocked or embossed wallpaper is going to have texture that will show through the paint. And, if you paint over wallpaper that has mildew, the mildew will simply grow through the paint.

In older homes wallpaper was usually applied to unprimed and unpainted surfaces. Removing this wallpaper will damage the wallboard or plaster, often to the point that it will need replacement. If several layers of wallpaper have been hung over each other or if several coats of paint are already on the wallpaper it could be too difficult or time consuming to take it all down.

Check Out Your Current Wallpaper

Obviously if your wallpaper is falling off the walls it has to come down. Even when wallpaper looks snug, it often starts to come unglued at the seams when you start painting over it.

To test how “glued” your wallpaper is find an inconspicuous location. Use a plant mister filled with a cup of warm water and a couple of tablespoons of white vinegar. Mist the seam but do not soak it. Wait for it to dry. If the wallpaper curls back at the seams you should consider removing all the wallpaper. The old adhesive will not take the weight or moisture of the primer and paint.

If you have wallpaper that is loose in areas and has mildew on it figure out what is causing the problem. Use painter’s tape to fasten a piece of plastic wrap (about 12” x 12”) over the surface. Be sure to seal all the edges of the plastic. After several days check the outside surface of the plastic. If it has moisture on it, it is caused by condensation in the room and a dehumidifier is needed. Remove the plastic and check for moisture on the wall and on the backside of the plastic. If it is present, it is coming from the wall and indicates some type of leak, possibly from a roof, flashing, or caulking problem. Before any wallpaper repair or painting can occur this will have to be fixed.

Painting Over Wallpaper

Wallpaper that passed the “seam test” but has some loose sections or bubbles can be repaired with wallpaper paste or household white glue. Cut the bubbles with a razor blade or thin knife. A small disposable mouth syringe filled with glue or paste works to get the glue under the loosened paper. Roll over the area with a rolling pin while the adhesive is wet. Wipe off the excess with a damp sponge.

If the paper is holding tight and repairs to cracks and dings are filled with non-shrinking spackle, float over the seams with a skim coat of joint compound or dry wall mud. If the paper has texture the whole wall will have to be done. When the joint compound is dry sand with 120 to 220 grit sandpaper or use a sanding sponge available at paint and hardware stores.

Wipe over the entire surface with a damp rag to remove any sanding dust.

Use clear or white paintable caulk along the ceiling, baseboard, and trim to secure the ends of the wallpaper.

Do not use a water-based primer over the wallpaper because it will soak through the wallpaper, dissolving the adhesive and causing the wallpaper to lift off the surface.

Apply an oil-based primer or shellac-based stain-blocking primer over the entire wall. If the wallpaper is dark, apply two coats of sealer. Allow for plenty of fresh cross air ventilation.

Primer over wallpaper will take longer to dry — Wait at least 24 hours for the primer to dry before painting.

Stripping the Wallpaper

Some do-it-yourselfers suggest removing wallpaper by wetting it with a home brew mixture of 75% fabric softener to 25% warm water. Others use a mixture of one part warm water to one part white vinegar. These mixtures are sprayed on the wallpaper after everything it could drip on has been covered with newspapers or plastic sheeting.

It may take 15 minutes for the solutions to soften the wallpaper paste, and it may take multiple applications. Don’t over-soak the areas because this will damage the surface beneath the wallpaper.

Commercial wallpaper removers are available; some even are gels which will help to eliminate dripping. Follow the label directions because these are chemical strippers and can be toxic.

To help the solutions penetrate the wallpaper use a “Paper Tiger”: a small hand-held tool with small pins attached to wheels. By rolling the scarifying tool over the wallpaper, hundreds of small holes penetrate the wallpaper but not so deep to damage the wall beneath.

Rent a wallpaper steamer

Renting a wallpaper steamer can speed removal of difficult areas. The steamer plate is pressed against the scored wallpaper so the warm mist can penetrate and loosen the wallpaper adhesive.

Lift the edge of the wallpaper with a four to six-inch wide drywall knife. By holding the broad blade knife flat against the wall the corners of the blade will not damage the wall surface.

Once the edge of the paper is lifted, pull the paper away at a slight angle rather than straight up from the wall. This will help to keep the paper from ripping and will save time.

The easiest wallpaper to remove will be peelable or strippable papers, most of which are paper-backed vinyls.

After the paper is stripped go over the surface with a mixture of vinegar and water or a solution of wallpaper remover to remove all traces of wallpaper paste.

If you strip the wallpaper off but some remains too stubborn to remove, apply a film of drywall mud to the area to level the wall to the paper that remains.

Fill all holes

Fill all holes and dings with vinyl non-shrinking spackle.

When the area is dry apply a high-build primer, a polyvinyl acetate (PVA) suitable for drywall and plaster. If the area is unfinished wood use an oil primer.

Painting

It is best to select a low sheen paint when painting over primed wallpaper or over walls that have been stripped, repaired, and primed. Low sheen paint reflects less light than higher gloss paint so surface dents and dings are less apparent. Painting over wallpaper or repaired surfaces will require two coats of paint. Some do-it-yourselfers add a fine sand mixture (available at paint stores) into the paint so it reflects less light, making surface imperfections and seams less visible.