What are the correct proportions for stucco? Is there a difference between the coats?
The brown coat is applied over the scratch coat to prepare the plaster base for the finish coat application.To start with, some systems are made up of two coats and some are three. Three-coat work is for systems that are constructed with lath and two-coat work is for direct application to masonry or concrete backup. The three coats consist of two base coats and one finish coat. The first base coat is called a scratch coat, the second is called a brown coat. In two-coat work, there is a single base coat and a finish coat. The purpose of the first base coat, the scratch coat, is to embed the metal lath and provide a base for the brown coat. The scratch coat gets its name from the fact that it is physically scratched with horizontal marks. These scratches create a “key” for the next coat to grab onto and a shelf for moisture to aid in curing of the brown coat. The brown coat covers the first base coat and creates a plane surface, leading to the best possible results for the finish coat. T
