Before applying any texture, the walls must be clean and smooth. Doing minor repairs will help achieve the desired look no matter which texture is chosen. To smooth out already textured walls, apply a layer of joint compound, the material used to close joints in drywall, with a trowel. The amount of compound will vary depending on the amount of texture that is present- - apply enough to cover the existing texture. This is also the technique to achieve a standard smooth coat, the style in most modern homes. It is inexpensive and allows for painting, wallpapering or texturing later on.
The orange peel texture gets its name because it ends up with a texture similar to that of an orange peel. Application is easy enough for novice do-it-yourselfers, but they need some practice to get it right. Practice a bit on a disposable piece of drywall before starting on the wall. The process requires a hopper gun- - a setup that includes a gun-like nozzle and trigger arrangement that is attached to a hopper and air compressor. The texture comes from spraying a drywall compound onto the walls. Orange peel is generally a light texture, but you can adjust it to a bit heavier.
Knock down texture is a style that resembles stucco, and may hide imperfections in the wall surface. To create the look, a watered down joint compound is applied with a sprayer or roller. As this soupy mixture dries, it drips and produces imperfections. Before these imperfections are allowed to dry, they are "knocked down" with a putty or drywall knife. You can do this knock down process from top to bottom, or if walls are imperfect, from side to side.
Plaster is a style of texture that often gives a Tuscan feel to a room. It is a heavy texture and proper application requires at least some practice. If plaster goes on incorrectly, it tends to crack or chip and is difficult to repair. Plaster products may be lime or marble based, and come in a variety of colors, which means they require no painting. Walls must be prepped prior to application, which includes a thorough cleaning, and they must be a low-sheen surface, preferably one coated with an eggshell or flat paint. The application process is by hand using a trowel, and includes a base coat, second coat and topcoat. For homeowners looking for something more low-maintenance, paint may be used to create a similar look. This technique requires a few layers of paint and a sponging technique, but will produce a sheen and look similar to that of Venetian plaster.