A method of manufacture of multilayer gypsum board, and a gypsum additive delivery system, including wet gypsum board passing through a board forming station in which additives are delivered to one or more layers of a multi layered gypsum board panels, such as engineered polymers, providing a better and more water resistance surface. Preferably, the gypsum board has a first layer of a mixture of set gypsum having an outer surface and a polymeric compound or wax emulsion additive entrained therein and impregnated in a thin sheet of randomly aligned inorganic fibers to essentially encase the core gypsum within two facing layers.