A DPC is a ‘Damp Proof Course’ which is a barrier inserted through the bottom of the wall to prevent water rising from the soil in to the wall. Older properties were not normally built with one, however the were introduced generally from around 1875. Older DPC’s were often made from slate however in modern construction they are now made from plastic. When a new damp proof course is installed as a remedial measure, this is normally installed by drilling into the walls and injecting a waterproof liquid or cream which forms the new damp proof course by creating a waterproof barrier through the wall.
One of the main concerns with damp walls is that timbers in contact with the walls are susceptible to decay. Advanced levels of dampness may also spoil decorations and damage plaster work.