Rising damp


Traditional building materials are typically porous which means that they contain capillaries (tubes or pores) that allow the transportation of moisture through them.

The amount the moisture rises is related to how much water is available for absorption, how porous the building material is, the salt content and how much evaporation occurs. The rising moisture is called rising damp.

If rising damp is found in a property, its cause needs to be found in order to solve the problem effectively.

The DPC may have deteriorated over time or damaged by builders letting the moisture travel up the building from ground level.

The DPC may have been bridged.

Prevention and cure

Make sure that there is no bridging of the DPC. Remove any plaster from the interior that crosses the DPC and dig away any soil from the exterior that crosses the DPC for example.

  • Make sure that there is adequate drainage to let rainwater run  away from the property properly.
  • Make sure the ground level is at least 150mm below the DPC level to allow for a certain amount of splash back of rainwater from the ground onto the property.
  • Air bricks below the DPC and interior floor level can help by circulating air to help keep the lower level dry.
  • Good airflow and adequate heating in and around the property will help to evaporate moisture from the walls.
Get a professional inspection

If there is or already has been damp in the property there could be hygroscopic salts present. The salts attract, absorb and retain moisture. This could mean that any work done to remove bridging, improve drainage and ventilation or even a replaced DPC could be ineffective at damp control. An inspection can quickly determine how prevalent the salts are, and to what extent re-plastering is required if any at all to solve the problem.

Call Oaks Preservation now on 0121 355 6007