The concept of an organic coating system consisting of a hot-melt coating (also known as thermoplastic coating), overcoated with a water-thinned coating while in the molten state, was explored by the development of solvent-free shop primers for forest-product-based exterior architectural components. These shop primers with and without commercially available finishes were compared to selected commercial coating systems on various substrates, by exposure to the weather in multiple locations. The concept is in its infancy, but coatings developed are commercially practical with performance equal or superior to conventional coating systems of recognized quality. Suggested applications of the concept include road marking and interior trim. The field is open for exploitation.