This paper describes the actual state of surface soiling for the specimen of porcelain tiles with sealing joint. Outdoor exposure test of the specimen inclined 35 degrees against the horizontal level was performed for 15 years. The color distribution of the specimen after 15 years exposure test was measured by an image scanning technique. Reduction of the value of tile surface was increased with the decrease of sealed joint depth from specimen surface. The edge of the tile surface tends to be soiled by dirt deposition. Reduction of the value of the tile specimen with polysulfide sealant was very low compare to the tile specimen with silicone sealant.
