PORCELAIN: there are two types of porcelain tile, glazed and unglazed. With glazed porcelain there is usually not a need or benefit to using a sealer. Unglazed porcelain tile comes in polished and unpolished finishes. Unglazed polished porcelain tile is susceptible to staining. This is due to the grinding or smoothing process used to polish the tiles. This process opens up microscopic pinholes and pores in the tile that were not previously exposed. and therefore, makes it susceptible to staining. You can test if a tile, glazed or unglazed, should be sealed by pouring water on the surface. If the tile changes color and absorbs the water, or some of the water, then you should consider sealing the tile.

Sealant Considerations: color enhancing/change, cooking areas, salt-water exposure (erosion), discoloring mold/algae, VOC compliance, stain resistance, general protection