Exterior Decorating: Distempering
In most cases the distempering or painting of exterior walls is done by applying the decorative materials on roughened surfaces, and the use of a paint-roller for coating outside walls is restricted to very smooth surfaces. The preparation of wall surfaces consists of cleaning the surfaces by brushing them with a hard, stiff brush. If the surface has been previously distempered or painted any loose and flaking patches should be removed by brushing, and it may be necessary to use a wire brush on these parts.
A wire brush should also be used if cement or concrete surfaces that are to be decorated have not been previously decorated and are thickly encrusted with dirt. After cleaning with a stiff brush, a soft brush should be used to remove dust or small particles. In most cases, with outside surfaces, the work of preparation may be done with stiff and soft sweeping-brushes. The handyman-decorator is not recommended to use new distemper brushes on exterior wall surfaces. These surfaces are very hard on new brushes and will quickly wear them down. The best tool to use for recoating walls is an old distemper brush. Emulsion paints may be used for outside wall surfaces but they are not suitable for use on woodwork or metal