ABSTRACT

ABSTRACT: The effectiveness of two permanent anti-graffiti treatments, a commercial fluoroalkyl siloxane and an organically modified silicate (Ormosil), in two artificial building materials, brick and lime mortar, was analyzed. The research was based on the assessment of the physical properties, cleaning efficiency and durability of the coated construction materials. The results showed that both treatments induced minimal chromatic variations in the materials surface. Ormosil was a better water repellent for its greater capacity to fill the pore systems that enhanced materials resistance to freeze-thaw cycles while lowering their water vapour permeability. Graffiti (alkyd spray paint) cleaning was satisfactory for the brick, after 4 cycles, particularly with the commercial anti-graffiti. On the other hand, lime mortar resisted only one cleaning episode, which removed not only the paint, but part of the material surface.