Another Print on the Wall

Digitally produced graphics are an excellent option for decorating interior or exterior wall surfaces. In addition to being decorative, they offer great commercial potential. You may have noticed many such advertisements in airport terminals.

The ads, which comprise pressure-sensitive materials, can be changed weekly, monthly or yearly with little or no wall damage. Pressure-sensitive wall graphics are also common in shopping malls, museums and other high-traffic locales.

This article will guide you through the process for preparing a wall surface, choosing the correct film and the proper installation process.

Surface preparation

A high-quality wall begins with a properly prepared surface. The wall surface must be clean, smooth and dry before the installation. This means fixing any damage to the wall surface and using a recommended paint finish, as well as properly cleaning the wall before applying the graphics. Failure to follow these steps could cause premature failure.

Repair

Normal wear and tear may damage wall surfaces. If defects aren't repaired, the graphic's adhesion could fail and incur damage when removed. Minor dings and scratches can be fixed by priming and painting – but holes in walls must be patched first. Here are some wall-damage examples you might encounter when preparing a wall graphic:
• Chipped paint or chipped walls, which can be fixed by priming and then painting the damaged area;
• Gouged wall surfaces, which may require filling before priming and painting; or
• Torn paper, which, when present on drywall, should be removed. Then, depending on the depth, the area may need to be filled before priming and painting.

Paint

The correct paint finish measurably impacts a successful graphic installation. Pressure-sensitive media manufacturers recommend using high-quality, gloss or semi-gloss paints. Matte, satin or luster paints aren't recommended — the matting agents that create these finishes can reduce film adhesion and trigger failure. Freshly painted walls should be allowed to dry/cure according to the manufacturer's recommendations. This time period is usually seven days; however, some paints need months to cure.

Cleaning

Wiping interior wall surfaces with clean, lint-free towels will be sufficient for most wall applications. If heavy grease or dirt mars the surface, mix a trisodium-phosphate (TSP) solution, according to the manufacturer's directions. TSP is available at most hardware stores. After cleaning with TSP, allow time for the surface to dry.

Film selection

Before choosing the material, ask customers a few key questions. Their answers will determine the best product for the job:
• To what type of surface will the graphic be applied?
• How long must the graphic last?
• What type of finish do you want?

The choice of cast or calendered film depends on the surface texture. For most smooth surfaces, a calendered film will work. A cast film will also function, but may be overkill because it costs more and may exceed job requirements. However, a textured surface, such as sealed cinderblock, may mandate a cast film, especially if it's a long-term job. Cast films can be heated and conformed to the wall's texture using a rivet brush, which can provide a painted-on appearance.

In addition to surface texture, durability impacts the film-selection process. If the surface is relatively smooth, cast and calendered films, as well as permanent or removable adhesives, will all work. If the project's lifespan is three years or less, an economy-grade, calendered film will be a sufficient, economical choice. However, an application that exceeds that timeframe demands a higher-performance cast or calendered film.

Testing the film

Once you've narrowed down your film selection to two or three options, apply small test swatches to an inconspicuous area and test your adhesion. Wall and paint surfaces vary greatly, so this test will insure you've chosen the right material for the job.

I tested three films on a cinder-block wall by allowing them to sit for a few days. In my opinion, the cast, permanent-adhesive film was the most attractive. The calendered film with permanent adhesive finished second. Conversely, the calendered material with removable adhesive already started lifting on the edge, which means that film shouldn't be used. I conducted the same test on painted drywall and found that any of the three films adhered acceptably.

Application

Here's a list of tools you'll need when installing wall graphics. Every job may not need every tool on this list, but include each in your toolbag:
• Two-in. masking tape for positioning (I like blue painters' tape to avoid damaging the wall);
• Lint-free cleaning cloths to clean the wall;
• A tape measure for positioning;
• An air-release tool to remove air bubbles;
• A marking pencil to identify graphic position;
• A squeegee to apply the graphic;
• A rivet brush to work into textured surfaces. A 3-in. rivet brush is ideal;
• A heat gun to conform the vinyl on complicated surfaces (if you use a torch, be careful not to damage the wall underneath); and
• A surface-temperature or IR thermometer to check surface and ambient temperatures.

Use only the dry-application method. Water or application fluid can damage the wall and cause premature graphics failure.
After preparation, lay out your graphics for installation. Before you begin the actual install, tape the graphics into position to ensure the graphics are sized correctly. If you find any problems, don't cheat — start over if you must.

After you tape the graphics into place, begin positioning. Because the entire mural hinges on the first panel, correct placement is paramount. Use a level to make sure the panel is completely vertical, or follow the line where the adjacent walls meet. Depending on the graphic's size and location, a second set of hands will be very helpful for the first panel, if not the entire project.

For this installation, I started applying each panel at the top (the top-hinge method). After taping and aligning the graphic, separate the film from the liner and remove the excess liner — this can be done by cutting the liner away or tucking it behind the graphic — then apply the graphic's top edge to the wall.

With the graphic attached at the top edge, I continued with the application by slowly pulling the liner paper back approximately 12 in., and then continued to apply the graphic using firm, overlapping strokes with the squeegee.

Repeat the process of taping the panels into place to ensure good alignment, and hinge the top on each panel until all are applied.

In this application, I encountered some electrical outlets. For the outlet that was flush to the wall, I applied film directly over the outlet and then trimmed around the plug receptacles and the outlet cover. If you do this, be careful to avoid shocks. I recommend turning the electricity off at the breaker. I trimmed the film around the outlets that protrude from the wall.

Once all the panels have been applied, vinyl manufacturers recommend flattening all edges with a squeegee to help ensure good adhesion and reduce the risk of lifting and damage. Congratulations, our wall-graphic installation is now complete.