Iranian researchers waterproofed building materials with very high efficiency by using the green and noncorrosive heteropoly acid catalyst.They used a specific type of organosilicon polymer at nanometric dimensions in this research as the waterproof coating, and they calculated the optimized conditions of the process by designing an experiment through the sol-gel method.In addition to avoiding water and decreasing the pollution to its minimum level, the building coatings produced in this research strengthen the building façade against UV, and they can be used in the interior and exterior parts of the building due to their invisibility.Various materials can be protected against water by using the results of the research including concrete, cement, cement blocks, roof cement plates, mortar, mosaic, various types of natural and artificial stones, soil, slurry, brick, tile, and clay stuff. It is also an effective step towards the protection and conservation of the newly built buildings.Results of the research have been published in 2013 in Progress in Organic Coatings, vol. 76, issue 3-2. For more information about the details of the research, visit the full paper on pages 384-387 of the same journal.