Product characteristics. Most wallcoverings have the following three layers, each of which performs an important function:
- The decorative layer, which is the top layer, is comprised of inks and a protective polymer coating applied to the top of the intermediate layer. Normally the thinnest layer, the decorative layer is usually the major reason a wallcovering is chosen. The design and/or texture is printed using various methods such as gravure, flexography, surface printing and screen-printing.
- The intermediate layer, or the ground, provides the surface upon which the decorative layer is printed. It also provides the background color which, while often an off-white, can be any color depending upon the design. This layer can range in thickness from less than one mil to as much as 30 mils in heavier-weight, "solid-vinyl" products. (Note: A mil is 1/1000 of an inch.)
- The substrate or backing is the portion of the wallcovering that goes against the wall. This backing can be of a wide variety of materials ranging from woven and nonwoven fabrics to lightweight paper products. Substrates are used in the manufacture of vinyl wallcoverings because vinyl itself is not peelable if placed directly on a wall.
The combinations or constructions of these various layers and materials provide the characteristics typical in wallcoverings such as degrees of strength or durability, scrubbability, washability, stain resistance, abrasion resistance, colorfastness, etc.
Heavy-duty vinyl wallcoverings are recommended wherever walls are subjected to severe abuse, such as high-traffic areas in healthcare, institutional, corporate, retail and hospitality interiors. Vinyl protects walls, wears longer than paint and is less expensive to maintain. In very demanding areas, rigid vinyl sheet provides the most durable protection without compromising aesthetic benefits. Even tough commercial product lines are available in appealing and varied designs, including warm color palettes and floral patterns that combine beauty with heavy-duty performance. Vinyl wallguards, chair rails, corner guards and kick plates complete the protective wall system.
There are several categories of vinyl wallcovering, each with specific performance characteristics:
- Vinyl coated paper (VCP) - A paper substrate coated with acrylic. Although more resistant to grease and moisture than plain paper and suitable for residential kitchens and bathrooms, it does not resist excessive and prolonged exposure to grease, moisture or abuse. Thus, it is not suited for commercial applications.
- Paper-backed vinyl/solid sheet vinyl (PBV) - A paper substrate coated with a vinyl plastisol. This sheet is thicker than the plastisol coating and provides greater durability. This type is classified as scrubbable and peelable, and can be used in most areas of a residence or business since it resists moisture, stains and grease. It will not withstand hard physical abuse, however.
- Fabric-backed vinyl (FBV) - A solid vinyl intermediate layer laminated to a woven or nonwoven fabric substrate. The vinyl layer can vary from two to 35 mils in thickness. The thickness of the woven fabric is about 10 mils and that of the nonwoven fabric is about six mils. Fabric-backed vinyls usually are strippable and unpasted, and provide a vapor barrier that will keep cold air in and warm air out. Three types are available to meet different situations (as distinguished in the federal wallcovering specifications FS CCC-W-408D, Wallcovering Vinyl-Coated, and Chemical Fabrics and Film Association, Inc. (CFFA) specification 101D):
- Type I: For less heavily traveled areas subject to minimal scuffing and abrasion, such as above chair rails in hotel guest rooms and office buildings.
- Type II: For general use in areas where traffic and scuffing are major issues, such as foyers, lounges, corridors and classrooms.
- Type III: Primarily used as wainscot or lower protection for areas exposed to heavy traffic by movable equipment or rough abrasion, such as hospital corridors, storage and utility rooms, food service areas and elevator foyers.
- Rigid vinyl sheet - A solid sheet wallcovering developed for use in commercial areas where the potential for high-impact damage is of concern. This product does not usually have a backing and is installed with special contact adhesive.
Manufacturers of vinyl wallcoverings have taken steps to address mold and mildew problems that are of concern especially in the southern coastal areas of the United States. The primary cause of mildew is condensation caused by warm, humid air infiltrating the wall cavity. Because vinyl wallcoverings are fairly impermeable, they act as something of a vapor barrier trapping moisture inside the wall cavity, where it condenses against the relatively cool inside surface of the wall. This is called "concealed condensation." Prolonged exposure to these conditions will result in deterioration of the gypsum board, allowing the growth of mildew. A permeable membrane, such as Tyvec®, on the outside wall part of the wall cavity helps vent moisture.
It is important to eliminate the moisture at its source, with proper window installation, caulking and sealing, for example. Proper wall preparation is also important, as starch-based wallcovering adhesives can serve as a food source for microorganisms that may be present on damp surfaces. In areas of concern, wallcovering systems that include adhesives and primers formulated to inhibit the growth of mildew should be specified.
Even wallcoverings that are labeled "mildew resistant" can trap condensation. Some manufacturers have introduced "microvented" wallcoverings that allow moisture to escape. If water infiltration problems exist within the building, "breathable" wallcoverings should be selected to avoid mildew problems.
Technical data. Residential wallcoverings vary from 20-1/2" to 28" in width and 13-1/2' to 16-1/2' in length, which yields a single roll between 27 and 30 square feet. Residential wallcoverings may be priced by the single roll, but are generally packaged in double or triple rolls.
Commercial wallcoverings are commonly sold by the lineal yard and are generally 27", 48" or 54" wide.
The following terms are commonly used to describe important characteristics of wallcoverings:
- Washable means that a wallcovering can withstand occasional sponging with a prescribed detergent solution.
- Scrubbable means that a wallcovering can withstand scrubbing with a brush and a prescribed detergent solution. (No abrasive cleanser should be used.)
- Stain resistance is the ability to show no appreciable change following removal of different types of stains such as grease, butter, coffee, etc., after a set period of time.
- Abrasion resistance is the ability to withstand mechanical actions such as rubbing, scraping or scrubbing.
- Colorfastness is the ability to resist change or loss of color caused by exposure to light over a measured period of time.
- Peelable means that the decorative surface and ground may be dry peeled leaving a continuous layer of the substrate on the wall which can be used as a liner for hanging new wallcovering. Peelable wallcoverings today are usually paper-backed vinyl products in which a paper substrate is coated with a vinyl plastisol.
- Strippable means that the wallcovering - complete with the substrate - may be dry peeled. Fabric-backed vinyl wallcoverings are usually strippable.
Installation. One of the most critical parts of wallcovering installation is proper preparation of the wall surface to insure that the wallcovering will adhere properly. The surface must be clean, dry, structurally sound and free of grease, mildew or other stains. Gloss and semigloss paint must be sanded to dull the surface and a coat of adhesion-promoting primer applied prior to wallcovering installation. Any wall irregularities should be repaired, then the wall surface primed and sealed. Stains or mildew must be removed to prevent bleeding through the wallcovering.
Surface treatment will vary according to type. New drywall, new plaster and painted surfaces must be primed. Liner paper may be required on masonry and paneled walls. Walls from which old wallcovering has been removed must be sanded or cleaned with an adhesive remover to prevent the development of mold and mildew.
Another critical issue involves the choice of adhesives, which are formulated for specific applications and vary in level of wet-tack, strippability and ease of application. Heavyweight vinyl wallcoverings require specifically formulated adhesive. See the manufacturer's instructions to select the proper adhesive for the application.
Detailed instructions for proper installation are available from the Wallcoverings Association. (See Section IX, Resources.)
Cost. According to data from RS Means (Building Construction Cost Data, 57th Annual Edition, 1999), the total cost of materials, equipment and labor for installation of a lightweight (Type I) fabric-backed vinyl wallcovering is $1.04 per square foot. Installation of a medium weight (Type II) vinyl wallcovering is $1.34 per square foot. This includes material costs of $.63 and $1.15 per square foot, respectively. By contrast, the cost per square foot for paint (two coats on concrete, dry wall or plaster) is $.46 and for paper-backed linen wallcovering is $1.69 per square foot.
Industry studies show that, on average, vinyl wallcoverings can be serviceable for 10 to 15 years. When figuring materials, labor and maintenance costs over the life of the material (including cleaning and repair every three years), vinyl costs $1.84 per square foot, compared to $2.70 for paint, based on The Hite Formula, which was developed for The Bell System by Jim Hite.
Maintenance requirements. Vinyl wallcoverings are more resistant to scratching and tearing than alternate coverings. Typically, vinyl wallcoverings last three to five times longer than other surface treatments, such as paint.
Low-cost maintenance consists of cleaning with mild detergent to remove accumulated dirt, grease and most stains without damage. Virtually invisible repairs can be made to severely damaged areas by using surplus material.
Always refer to the manufacturer's guidelines when cleaning wallcoverings. Stains should be removed as soon as possible to eliminate any possible reaction between the stain and the wallcovering. If soil remains on the wallcovering too long, permanent discoloration may result. Ordinary dirt spots can be removed with a mild soap and warm water. Rinse thoroughly with clean water. Blot wallcovering dry with a soft, lint-free towel. For more difficult stains that are only surface deep, a stronger detergent is recommended. Try an inconspicuous spot first before attempting the entire wall. One should always rinse after applying a detergent. Abrasive rubbing of spots should be avoided. Use of steel wool, powdered cleaners or active solvent-type preparations, such as nail polish remover, tar and bug removers, etc., may damage the wallcovering.