Despite the remarkable durability of today's wallcoverings, they are not indestructible. When damage occurs or flaws turn up, it's best to fix them as soon as possible. The longer you wait, the larger they get; the larger the defect, the tougher the repair job.
Blisters, which result from excess adhesive or air trapped in bubbles between the wall and the backside of the wallcovering, can show up within minutes, days, weeks, or even years after a project is finished. The easiest way to deal with blisters is to prevent them in the first place. Smooth out a newly applied strip of paper thoroughly with a smoothing brush, a straightedge, or a sponge. If you encounter blisters, work them toward the nearest edge of the strip to release trapped air or excess adhesive.
Blisters located in inconspicuous places won't be noticed. If you're using an untreated printed paper, small blisters may go away by themselves as the paste dries and the paper contracts. However, if a blister is still there an hour after the strip has been applied to the wall, it's not likely it will disappear on its own. Blisters that are only an hour or two old can often be repaired following these steps:
Step 1: Use a straight pin to puncture the blister.
Step 2: With your thumbs, gently squeeze out the trapped pocket of still-wet adhesive or trapped air through the hole, being careful not to tear the paper.
Step 3: If that doesn't work, use a single-edge razor blade or utility knife to slit a small X in the wallcovering, and peel back the tips of the slit.
Step 4: If there's a lump of adhesive underneath, gently scrape it out. If the air was the cause, use an artist's brush to apply a small amount of adhesive behind the flaps, then press the flaps back down. Edges may overlap a little, but this overlapping is seldom detectable later.
Repairing Loose Seams
Loose seams are even easier to repair. Here's how:
Step 1: Lifting the seam slightly, use a brush to work the adhesive under the seam. Press the seam back down and go over it with a seam roller. If you find a loose seam in an overlapped vinyl wallcovering, use a vinyl-to-vinyl adhesive to stick it back down.
Step 2: If a seam shows any tendency to pull away, tack it in place with two or three straight pins stuck through the paper and into the wall until the adhesive is dry. Tiny holes won't show.
Repairing Holes and Tears
Holes and tears in wallcoverings require more effort to repair, but, if done carefully, the repairs will be nearly invisible. Here's how:
Step 1: Use a single-edge razor blade or utility knife to trim off any ragged edges around the damaged area.
Step 2: Tear out a patch from a piece of scrap wallcovering that is slightly bigger than the damaged area. Hold the scrap printed side up with one hand, and the rotate scrap as you gently tear out a round patch. With practice, you'll have the patch with an intact design on the printed side of the paper and a slightly feathered edge on backside.
Step 3: Spread a thin coating of adhesive on the back of the patch, and place it over the damaged area.
Step 4: Line up the pattern on the patch with the pattern on the wall as best you can. A perfect pattern alignment may not be possible, but the match should be close enough to escape detection.
Another technique for repairing holes is called double cutting. With this method you create a patch that is perfectly sized to fit the damaged area.
Step 1: Cut out a square scrap of wallcovering about an inch larger all the way around than the damaged section.
Step 2: Place the scrap over the hole, and align the pattern with the pattern on the wall. Hold the scrap in place with masking tape or thumbtacks, whichever is the least likely to damage the wallcovering.
Step 3: Hold a metal ruler firmly against the wall over the scrap, then use a very sharp utility knife to cut a square slightly bigger than hole itself through both layers of wallcovering.
Step 4: Remove the scrap and square patch you've just made; set it aside. Use the end of a utility knife to lift one corner of the original wallpaper square with the hole, and peel this square off the wall.
Step 5: Apply the adhesive to the back of the new patch, and press it into the cleaned-out area on the wall, making sure the patterns are once again aligned.
Now that we have the basics out of the way, it's time to get a little fancy. In our final section, we will learn how to hang specialty wall coverings, such as vinyl, fabric, or foil.