5 Tips on Preparing Metal Roofs for Roof Coatings Roof Coatings are a very affordable option to repair and restore an aging metal roof. Roof coatings extend the life of a roof. When a reflective coating is applied, it can reduce heat transfer into the building and decrease thermal shock. Roof coatings are also very effective in stopping leaks. The successfulness of a roof coating depends strongly on a sufficient preparation and cleaning of the roof before a coating application. For the purpose of this article, we would like to concentrate on the steps to prepare a metal roof for a roof coating application.