1. Why wallpaper ? Isn't it easier to paint? 2. What type of wallpaper should I purchase? 3. It's being covered with wallpaper. Why do I need to do wall prep? 4. Can't I hang over the existing wallpaper ? Why does the old wallpaper have to be removed? 5.Do I really need to prime? 6.For years, I have primed for wallcovering with oil based enamel undercoater. My paperhanger now says this is not a good idea. What gives? 7. I was advised to paint the wall to be papered with oil base enamel undercoat and then another coat of acrylic wallcovering primer. Why two coats? 8.This bath took six rolls last time. Why does it need eight rolls this time? 9. What type of wallpaper should I use in a bathroom, kitchen, or laundry room? 10. What is a pattern repeat? 11. What is a random, straight across or drop match? 12. How hard is it to take off wallpaper ? 13. What is double cutting? Why do you need to? 14. Why is paper packaged by double roll, but priced by single roll? 15. Why is this expensive paper not pre-trimmed? 16.What is a "euro roll" as opposed to an American or Metric? 17. What is sizing? 18. Why does liner have to be installed before wallcovering? Why wallpaper ? Isn't it easier to paint ? Probably, but a well done wallpaper job may last 15 to 25 years with a look that you cannot get from paint. The wallpaper and installation is paid for once, as opposed to multiple purchases of paint and labor to paint over the same period. People have wallcovering installed for much the same reason that they drive a Chrysler or a Cadillac instead of a Yugo. What type of wallpaper should I purchase ? Here are some pointers: If you are wallpapering in a bathroom with a tub or shower, a kitchen, or an area that has high traffic or one that will receive wear, you'll have better luck with a wallcovering that will resist moisture and is washable. A solid vinyl will be best for these areas, preferably one with a canvas or scrim backing. In many cases a paper backing may work fine, but the backing may absorb moisture and begin lifting or delaminating. For other areas of the house that are less "wet", a wider range of wallcovering will be acceptable. It's being covered with wallpaper. Why do I need to do wall prep ? It is sometimes assumed that wallcovering will hide discrepancies and flaws in the wall surface. Not necessarily ! Flaws in the wall surface like nail holes, small bumps and grit, even texture caused by brushing and rolling paint, can sometimes show through a layer of wallcovering. Wide open patterns, light backgrounds and shiny wallcoverings are more likely to show wall surface flaws. Can't I hang over the existing wallpaper? Why does the old wallpaper have to be removed? Aunt Sadie used to hang over old stuff all the time, and she did just fine. It is almost always a bad idea to hang wallcovering over a previous layer of wallcovering. A paper or vinyl may seem to be firmly adhered to the wall, but the addition of another layer can cause failure. As the new wallcovering dries, it exerts tension on the first layer that can affect it's adhesive bond. Prominent seams and irregularities in the previous layer can telegraph through the new layer. Bubbling of the first layer can also be a problem. There are cases where the previous layer is so well bonded to the wall surface that removal is not practical because of the amount of time and money that would have to be spent on the removal. If this is the case, repair of irregularities in the previous surface should take place and then a coat of penetrating sealer should be applied to seal the repairs and the wallcovering surface. Aunt Sadie probably used a paper product that had a higher success rate for multiple layers, but if you looked closely you would probably have seen some irregularities showing through from the original layer. Do I really need to prime ? Priming provides a sound surface that wallcovering will adhere to. Priming will aid immeasurably when it comes time to remove the wallcovering for redecoration. If you are sure that your wall surface is sound and adhesive friendly, priming may not be necessary. For years, I have primed for wallcovering with oil based enamel undercoater. My paperhanger now says this is not a good idea. What gives ? For years, oil base primer was the way to go, but with recent passage of clean air laws, manufacturers have been forced to change their formulations. Complying with these VOC laws has changed the properties of the finish surface, so that it is no longer a reliable adhesion promoting surface. I was advised to paint the wall to be papered with oil base enamel undercoat and then another coat of acrylic wallcovering primer. Why two coats ? Some wall surfaces require a penetrating sealer to soak in and firm up a questionable surface. As stated before, this paint does not provide a reliable surface for adhesion. The second coat of acrylic wallcovering primer will promote adhesion and give you a better chance of success. There have been recent advances in paint technology that have resulted in a few products that will do both jobs. This class of water-based penetrating sealers that will promote surface adhesion to wallcovering include "Draw-Tite" from Scotch Paint (CA) and "Gardz" from the Zinsser Company (NJ). This bath took six rolls last time. Why does it need eight rolls this time? There are several variables. The pattern repeat and the match will have an effect on the amount needed. With a different repeat or type of match than last time, there may be more waste, requiring a greater amount. Different companies package their product in differently sized rolls. There have been changes in manufacturing standards in the last few years that have decreased roll sizes. Needing more rollage than was needed for the same space a few years ago is becoming very common. What type of wallpaper should I use in a bathroom, kitchen, or laundry room? A solid sheet vinyl will be best for these areas, preferably one with a canvas or scrim backing. Paper backing may work fine, but if the backing absorbs moisture, it may begin lifting or delaminating. For other areas, a wider range of wallcovering will be acceptable. What is a pattern repeat? The pattern repeat is the vertical distance between a design element, say, a yellow daisy, to the exact same daisy, further down the pattern. What is a random, straight across or drop match? The match is the point at the seam where a design element is continued to the adjacent strip. With a random match, there is no pattern to match With a straight across match, each strip is the same as the previous strip. With a half drop match, the match point of each strip sits higher or lower than the previous strip, at the half-way point of the first. Every other strip will be the same. With a multiple drop match several strips will all be different until you reach a point where the series will repeat itself. note : The above is true, assuming that the ceiling and baseboards are level. Sloped ceilings and baseboards will have different tops and bottoms, but the pattern will repeat itself consistently across the wall. How hard is it to take off wallpaper ? Removal of wallcovering can range from a cake walk to a frustrating, exasperating experience. Type of wallcovering, adhesive and prior wall preparation will be the determining factors. You will most appreciate proper wall preparation at removal time. What is double cutting? Why do you need to? Double cutting is a method used by professional paperhangers to make a seam on the wall rather than trimming on the table. It is often superior to butting the factory edges, and with some wallcoverings, commercial vinyls, for example, it is the prescribed method. Why is paper packaged by double roll bolt, but priced by single roll? A roll is an increment of wallpaper quantity. A bolt is how it comes to you. Less waste is incurred if the bolts contain double rolls, that is why single rolls are rarely sold as singles, there would be too much waste. There is even less waste with triple or quadruple rolls. Why is this expensive paper not pre-trimmed ? Untrimmed papers are usually hand printed by the silk screen process. This gives an effect that cannot be duplicated in machine printing, but the technology is not as exact as that of machine printing. Machine trimming a hand printed product will gain or lose pattern because of these tiny inexactitudes, so it is left to the paperhanger to trim for maximum results. Some other types of wallcovering are shipped with selvage to protect them in shipping. What is a "euro roll" as opposed to an American or Metric ? For years, the standard American roll contained 36 square feet. With the advent of greater amounts of European goods, a metric increment of measurement arrived. The metric bolt is 10 meters (33 feet) long and usually about 21 inches wide. Most American made papers available at retail are gradually changing to bring the two into line for the sake of standardization. What is sizing ? Sizing originally referred to a glue like material that was manufactured from animal hooves, hides and bones. It was used to coat a wall surface prior to wallpaper installation to even out porosity and provide a better level of adhesion. Improvements in paint and adhesive chemistry have made size redundant. Nowadays, the word "size" is often incorrectly used to describe most anything you put on a wall, prior to wallcovering. Why does liner have to be installed before wallcovering? Liner may be a plain paper (known in the trade as "blankstock") that is applied to a wall surface prior to the decorative layer of wallcovering. It also may be a "bridging type" that seeks to provide a new surface when the existing surface has voids. The bridging type is more common, often pure white in color and is often composed of at least 50% synthetic ingredients such as rayon and polyester. Both types act as a buffer between the wall and the second layer of wallpaper. Many wallcoverings are of a delicate nature and can be damaged in the installation process. A layer of liner paper (blankstock) will absorb moisture and adhesive applied to it, easing the installation and lessening the chance of damage from overworking the finish paper. The use of liner, whether it is blankstock or a bridging type, will almost always improve the finished look. note : Bridging liners are effective at hiding small indentations, but cannot disguise even small bumps. They also have little effect on larger indentations or protrusions that change the contours of the wall.