Rising damp is due to capillary flow of water from the ground where a damp proof course is defective or not present. The damp zone will extend to different heights above the skirting boards depending on the pore size of the material the wall has been built from.
Decayed skirting boards, crumbling or salt stained plaster, discolouration and staining, decayed timber floors, peeling paint and wallpaper are all common when walls are affected by rising damp. Most types of masonry used in the walls of buildings will allow some water movement by capillary action; however, this is usually controlled by a physical barrier or damp proof course. If this physical barrier is absent, has broken down or is damaged then it is often possible to install a remedial damp proof course (DPC) to control water rising from the ground.
Water rising from the ground often introduces contaminating salts into the walls and plaster coats. This contamination will result in the need for the plaster to be removed and replaced using specially formulated salt resistant plasters.