Rising damp is the term used when moisture from the ground is drawn up brick or masonry walls. Strange as though it may seem, your wall can act a bit like a sponge, drawing up moisture in a movement known as capillary action.
The most common sign of rising damp in a home is staining that looks like a tidemark appearing on your wall, usually up to a metre above the skirting board. If you see these tidemark stains, or salt deposits on your wall, you may have a rising damp problem.
Most buildings are constructed with a rising damp barrier, also known as a damp proof course. However, this can fail due to several reasons, such as:
- It gets damaged by shifting foundations or the roots of trees
- It was not installed properly to begin with
- It has been ‘bridged’, which can happen when the ground level is higher than the installed damp proof course or plaster or render has covered the DPC
- General deterioration over time
Rising Damp Signs
Rising damp is relatively hard to identify correctly, so a professional survey is recommended in order to avoid miss-diagnosing the damp issue. It can be hard to distinguish rising damp from other forms of damp like condensation or damp penetration, and to do this requires an analysis of the wall fabrics.
Some of the more common signs of rising damp include:
- Crumbling mortar between bricks or stonework on the exterior of the building
- Flaky or bubbling plaster and decoration
- Damp or wet patches appearing on the walls
- Tidemarks and damp stains on walls
- Evidence of salt deposits on walls
Once our qualified surveyors have identified the cause of the problem, our trained technicians will carry out the remedial work specified by our surveyor to treat the rising damp.
We use a silicone damp proof course, as it is usually the best and most cost-effective way of rectifying the problem. The process involves drilling a series of holes in the wall and injecting the silicone cream into the wall. The damp affected plasterwork is removed and a membrane is installed prior to re-plastering.
A damp-proof course is essential to all properties to protect them from damage caused by damp rising from the ground. It forms a barrier between damp in the ground and the walls of your home. When this damp-proof course becomes compromised, rising damp can damage plaster, decorations and timber.
Most properties should have an existing damp proof course, whether it is bitumen in the mortar course or a plastic strip at around 150 mm above ground level. These are usually very effective, however building movement can damage the DPC and they can also fail due to old age.
One very common problem that we see is when homeowners have raised the external ground level above the existing damp proof course, also known as bridging. This might happen when you carry out landscaping to your garden or driveway, and it allows moisture from the ground to bypass the existing damp proof course and enter the property. When this occurs, we recommend the ground level is reduced to 150 mm below the damp proof course, otherwise a new damp proof course will have to be installed.
After more than 85 years of successful property surveys and repairs, we are confident in our service that we offer a 30-year guarantee on the installation of our new damp proof course that is transferred to the new owner if your property is sold.
Richardson & Starling are long standing members of the Property Care Association (PCA) and the Guarantee Protection Insurance scheme (GPI). This demonstrates our ability to meet technical and financial requirements, meaning we can offer an insurance back-up guarantee on top of our own long-term guarantees.
Our qualified surveyor will investigate the affected area and give advice on the best way to solve the damp problem. At Richardson and Starling, all our surveyors are trained in the types of damp and rot problems that can affect your property. This means that our surveyor will be able to complete the survey and give the appropriate remedial recommendations.