Purrender of walls is a spraying of a cement mortar and its distribution on the wall surface. If the processed concrete wall is smooth or brickwork is performed perfectly evenly, then the application of one or two thin layers of cement mortar will be sufficient.
If the wall has a surface far from perfect, then, most likely, you will need to apply three layers of a cement solution, in which it is recommended to add PVA glue to improve its waterproofing and clutch.
