Abstract: The method of maintaining the adherence of a permeable organic coating to a wall of a dishwasher which is exposed to water, water vapor or dilute aqueous solutions at temperatures higher than surrounding ambient by reducing or eliminating the formation of blisters between said coating and said wall and comprising the steps of selectively insulating the side of said wall exposed to ambient in those areas of greatest thermal gradient where blisters are most likely to form in the absence of such insulation, and sufficiently insulating said side of said wall in such areas that the temperature gradient across said coating is reduced to the point that the partial pressure difference driving force of the vapor across said coating is negligible and not more than the adhesion forces of said coating to said wall.