Rising damp is relatively rare, although it can occur if ground water is sucked up through the brickwork of a building. If the affected wall has porous building materials like timber, joists, or plasterwork, they will hasten the rising damp as they will absorb the ground water easily. Generally, rising damp will be noticed first on interior walls, where the plaster and paint will deteriorate, and a visible stain will appear in the form of a tide mark. The exterior wall may have salt stains on it or may be crumbling as a result of the water. The most common treatment for rising damp is the injection of Dryzone Damp Proofing Cream or Dryrod Damp-Proofing Rods.