Abstract: The invention relates to a method and compositions for producing a hydrophilic coating on a surface of a solid material. The method comprises a cleaning step and a coating step. The cleaning step may be preceded by an initial cleaning step and it may optionally be succeeded by a preconditioning step prior to the coating step. The cleaning step comprises cleaning and preconditioning a surface of a material by use of a first cleaning fluid composition comprising ceria (CeO2) particles. The coating step comprises treatment by use of a coating fluid composition comprising photocatalytically active nanoparticles of titania (TiO2). An advantage of the method of the invention is that the method may be carried out at temperatures in the range 5 to 50° C. No further heating is required. Thereby, the method may easily be used for treating materials such as windows, furniture, tiles, walls, etc.