Abstract: An insulation coating system for insulating a structure comprised of three flexible moisture barrier coatings; (1) a first coating comprising an elastomeric acrylic resin and an antimicrobial, (2) a second coating comprising an acrylic resin, a cement and fibers; and (3) a third coating comprising an elastomeric acrylic resin, a water repellant, an aggregate and an antimicrobial. The coatings adhere to the structure with an insubstantial amount of interfacial voids, and prevent a substantial amount of moisture from contacting the surface of the substrate.