Analysis of causes and development of measures to prevent efflorescence on brick walls in cold climate

The article attempts to identify the causes of salt efflorescence on building facades and to develop measures preventing such efflorescence. Physical and chemical factors promoting efflorescence on brick masonry were analysed. The effects of various antifreeze additives to cement mortar and water repellents on the spread of efflorescence were surveyed. Conventional and advanced antifreeze additives used in winter construction were studied. Antifreeze additives were admixed to mortar in the amount of 1.5 to 10%. During laboratory tests, the voids in brick samples were pre-filled with cement-sand mortar mixed with antifreeze additives. It was proven that certain advanced additives were able to prevent brick efflorescence. The article shows test results of water repellents used for preliminary integral treatment of facing bricks, for mortar mixing (as additives), and for wall treatment after efflorescence removal. The use of water repellents as additives to mortar and for surface treatment (coating) of wet brick walls after efflorescence removal has no significant effect on the area damaged by efflorescence. Laboratory survey showed that there was no efflorescence on the brick surface after preliminary integral treatment of the bricks with water repellents. The measures described in this article can help to decrease and, in some cases, entirely prevent efflorescence on building facades. In its turn, this will maintain the architectural appearance of the facades and ensure the long life of the walls.