The finish is one of many different decorative paint textures applied to walls and ceilings of a home. Finishes are rolled, sprayed or applied by a trowel.
Materials and Plaster Used
Joint compound is used to create the look of double knockdown texture. The plaster is thinned with water to the consistency of thin paint and sprayed onto the surface, using a spray gun. Hold the spray gun about 6 feet from the surface and move in a slow, even motion.
Technique
Once the plaster is splattered onto the wall, wait about 10 to 15 minutes for the plaster to set up. When ready, skim across the tops of the plaster to remove all peaks, using a drywall trowel. The size of the knockdown texture's islands depends on how hard you press the trowel into the paint. The harder you press, the larger and thinner the textured islands are. When preforming a double knockdown texture, the finish refers to at thick coating of plaster. The plaster may be applied once in a very thick form. Alternatively, you can plaster the wall more than once, creating a heavily textured look.
History
The most commonly used texture finish since the 1950s was the popcorn ceiling finish. However, in the late 1970s, it became illegal to use the product due to the material containing asbestos, a cancer-causing agent. Joint compound was then used to create a variety of finishes, often to mimic old-world-style stucco. This finish is popular because it doesn't chip, can be painted and is more subtle than the acoustical popcorn ceiling.
Benefits
A double knockdown texture is extremely thick and works well as a sound barrier, especially in homes with tile or hardwood floors. The plaster finishes may be painted over, glazed and colored. When drywall is imperfect or there are flaws in the detail work, a double knockdown texture generally hides these defects.