RISING DAMP - WHAT IS IT AND HOW TO IDENTIFY IT

Wed 26 Jun 2019

WHY SHOULD I WORRY ABOUT RISING DAMP 

Although rising damp can potentially occur in any building, it is particularly common in older buildings. This is mostly down to a previous damp proofing course that has failed or where the ground level around a building has risen. Rising Damp if left untreated will not just damage wall plaster but could also lead to timber decay in the form of dry or wet rot. Dry rot is arguably the worst possible property problem that can occur so it’s really important any signs of rising damp are not ignored. 
 

HOW DOES RISING DAMP OCCUR

When a building is being constructed, damp proofing courses are put in place to protect the building from damp problems occurring. For rising damp, a physical damp proofing course is installed in the walls to prevent natural moisture from finding its way into the structure of a building. Moisture naturally is always trying to find its way into a building and when a damp proofing course fails, the moisture is able to find its way into the porous brick and move its way up along the walls causing rising damp. This process of water moving up through the walls is known as capillary action.

SIGNS OF RISING DAMP

Rising damp is often confused with other forms of damp such as condensation so it is important to know the signs of rising damp and to treat it before it can lead to structural damage. It is important to emphasise rising damp can only occur on the ground floor of a property so any damp problems above the ground floor are more likely to be penetrating damp or condensation. 

Damp Staining or Tide Marks

One of the most frequent signs of rising damp is tide marks on walls. Tide marks will be apparent anywhere up to 1 metre above the skirting board and are caused by evaporation and salts from the ground. 

Yellow or brown damp stains are also a common sign of rising damp and also appear up to 1 metre above the skirting board. 

Decayed Skirting Boards

When rising damp comes in contact with timber, it is capable of causing rot which often leads to decayed skirting boards. Skirting may be cracked, easily crumbled or be accompanied with fungus. Keep a close eye on the paint on skirting boards as this may crack or appear flaky. 

Plaster Salts

When rising damp occurs, the ground water that travels up through the bricks contains soluble salts. As the water dries out, the salts are deposited on the wall in the form of white fluffy deposits.

Peeling Wallpaper  

Another common sign of rising damp in a property is peeling wallpaper. If there is a rising damp problem, the wallpaper is likely to first come loose from the skirting board and then begin to curl upwards. 
 

WHAT SHOULD I DO IF I NOTICE SIGNS OF RISING DAMP

The longer a rising damp issue is left untreated, the more expensive it will be in the long run to treat due to the potential for timber decay and structural damage. Rising damp is also often confused with other forms of damp. If you suspect rising damp in your property, it is strongly advised to have the signs examined by a damp surveyor who will either put your mind at ease or recommend a treatment plan be put in place.  

By Jake Ryan of Peter Cox