The primary function of acrylic roof coatings is to protect the underlying material from water, UV radiation, chemicals, and wear. They are typically applied either by roller or airless spray, from which the latter is increasing its share as the formulation technology is developing. Acrylic elastomeric coatings differ from standard architectural paints, as they typically have higher binder levels, as well as higher solids and have a typical viscosity around 100-130 KU.
Typical requirements for elastomeric roof coatings are high tensile strength with good elasticity, as well as good reflectivity and UV resistance. As roof coatings are exposed often to ponded water, good water resistance is also essential. However, some breathability is often needed as most of the roofing materials, such as concrete and tiles, allow the moisture to transfer from the inside of the building. Naturally, the need for breathability depends on where the building is located. Water-vapor drive is generally from areas of high vapor concentration to low vapor concentration, or from high to low temperature, meaning that the breathability is often more relevant for cold environments. In addition to good film properties, rheological properties are also important. In addition, elastomeric roof coatings are applied on several different materials, including new and aged ones, meaning that good dry and wet adhesion on various materials is essential.