What Rising Damp Is and How to Remedy It

Posted on: 17 October 2019

Wait, is that a patch of rising damp you see on your internal walls? If your walls are wet and the paint is peeling off as a result of the wetness, then you may have a rising damp problem in your house. If you have spotted signs of the problem in your home, it is important that you take remedial action before it is too late.

The following guide is intended to help you understand what rising damp is and how you can remedy it.

Rising Damp: What It Is

Rising damp is a problem that occurs when water from below the ground on which a building was built travels up the walls of the building by capillary action. Signs of rising damp are first noticed on the internal walls of a building, with plaster and paint showing signs of deterioration. Outside, you may spot white salt stains on the walls. 

Rising damp is a problem that requires urgent treatment because it tends to exacerbate over time.

Rising Damp Treatment: Repair or Installation of a Damp-Proof Course  

As a building safety requirement, every house is supposed to have some form of damp-proofing barrier installed at the bottom of the walls to stop groundwater from making its way up the walls by capillary action. This non-absorbent, water-resistive barrier is called a damp-proof course (DPC). It can be made of materials such as plastic, slate and bitumen, depending on the period the house was constructed. 

Over time, DPCs may fail. In older houses, they may not even exist. If your house doesn't have a DPC, you will need to have one installed to prevent the damp from travelling up your walls. If you have DPC but the damp still rises up your walls, this is a sign that the damp-proofing barrier has failed and needs to be repaired.

If the DPC hasn't been bridged in any way, you can fix it by injecting a specially formulated damp-proofing cream. If the existing DPC is worn out, you will need to install a new damp-proof membrane. Of course, this is a much more complex and expensive repair job than the injection process.

Since rising damp is less straight forward to handle, it can be quite difficult to treat. For this reason, it is always advisable that you hire a professional to deal with the problem on your behalf. They will carry out a damp-proofing survey of your house and help you fix any rising damp problems effectively.