Ugly walls that need refinishing present an especially difficult problem for do-it-yourselfers when the old surface is rough or damaged or is surfaced with old material that is difficult to remove.

Examples of these problem-wall surfaces are concrete blocks, old paneling, old ceramic tile, cracked plaster and badly peeled wallboard.

When I recently wanted to redo a wall that was surfaced with worn, prefinished plywood paneling that had been cemented and nailed to wallboard, I decided to save time and work by leaving the paneling in place and applying the new finish over it.

It was a made-to-order situation to test a promising new product called Paris Wall, a vinyl-faced covering that, the manufacturers said, can turn problem walls like those mentioned above into things of beauty.

I'm happy to say that Paris Wall passed the test with flying -- or at least with hanging -- colors. With very little preparatory work -- a few passes with some rough sandpaper to degloss the surface and a fast spackling of the grooves between the panel "boards" -- the ugly paneled surface was transformed to one that appeared to be covered with gleaming ceramic tiles.

The "tiles" are one of five styles of Paris Wall that are applied in sheets, much like wallpaper or other flexible wall coverings. The difference is that Paris Wall has special heavy, construction that enables it to span small gaps, cracks and other defects without "telegraphing" their presence. Here are a couple of other qualities that make Paris Wall uniquely easy to apply:

The adhensive -- a special material called Paris Wall Bond that is supplied in plastic tubs -- is normally applied to the wall with a paint roller, rather than to the wall covering itself. Anyone who has ever wrestled with a long, sticky piece of wallpaper will appreciate this feature. To apply the adhesive along edges and in other tight places, I used an old paint brush. After the job was done, I threw away the cheap brush and paint-roller covering, but was able to clean the paint tray neatly with warm, soapy water.

The edges of adjacent pieces are simply butted together, and the material is thick enough to make this easy. The joints are vitually invisible.

The rolls of Paris Wall are 31 1/2 inches wide and 9 1/2 feet long (about 25 square feet), so that a sizable area of wall can be covered with each strip. The material cuts easily, with either scissors or a sharp knife, and goes around corners neatly. Light pencil or ink marks can be made on the outer surface when special cutouts must be made, and the marks simply wiped off later with a damp cloth.

Although Paris Wall dealers sell a kit containing the tools necessary to install the coversing, many do-it-yourselfers already own most of the tools. Besides the painting and cutting tools already mentioned, Paris Wall installers will need a tape measure or rule, a wallpaper brush for smoothing the covering once it is on the wall, and a chalk line-plumb bob.

The chalk line-plumb bob is perhaps the most important tool; with it, the installer can make a straight vertical line on the wall so that the first section of covering is plumb when applied. If properly butted, all the succeeding sections installed will be plumb.

While my installation didn't extend to a shower or bathtub area, I understand that Paris Wall can be used in such locations if the seams between sheets are carefully made and waterproofed. A waterproof silicone caulking can be used at the joints and edges of these installations.