Rising damp

Rising Damp | Causes, Signs, Treatment & Cost

17 January 2017

Have you recently noticed damp on your walls? Are your walls damp to touch? Is plaster peeling away from the interior walls?


Accredited to

Robert Pool

Remedial Surveyor and Waterproofing Design Specialist CSRT CSSW
North West

If you answered yes to any of the above questions, then you’re in the right place! In this article we will discuss; what is rising damp? What are the signs of rising damp? And, most importantly how to treat it.

What Is Rising Damp?

Rising damp is a form of dampness that is present within walls as a result moisture penetration from outside or beneath the structure of the property. It is a particular problem in older buildings where the damp proof course (DPC) has become damaged or when the ground level around the house has been raised by the addition of a path or driveway. Any building that has a damaged damp proof course will run the risk of suffering from rising damp at some point or another. Dampness will rise via capillary action to a height of around 1 meter. Salt deposits may however be found at slightly higher points.

Signs of Rising Damp

Fortunately, there are a number of tell-tale signs for spoting rising damp before the problem can progress. These can easily be identified without the need for any professional equipment.

Typical signs of rising damp in a property include:

  • ‘tide line’ of yellowish or brownish staining or blown plaster in the lower area of your wall above your skirting board. Tide lines, or tide marks, are caused as a result of evaporation and salts from the ground. They are usually noticeable at heights of up to 1 meter above the level of the skirting board.
  • Damp or rotting skirting boards or flooring. Dampness and timber is never a good combination and wherever the two meet rot will not be too far behind. With rising damp it is usually the skirting boards that will show signs of rot first – look out for deterioration to the paint work.
  • Salt effervescent– You may see what look like white, fluffy deposits in your plaster – these are in fact ‘salts’ which the damp has washed out of your brickwork and into your plaster.
  • Black spot mould is a sure sign of a dampness issue. Once again if the mould is appearing around 1 meter from the skirting board it is almost certain to be as a result of rising damp.
  • Peeling Wallpaper is another very visual sign of dampness. The wallpaper will lose adhesion to the wall in areas close to the skirting board first. Lookout for the wall paper ‘curling ‘as this is a definite sign of a damp problem.

How To Treat Rising Damp

If you have allowed damp into your home then the probability is that issue is easily rectifiable. Mould growth can easily be eliminated through the application of a high-intensity Mould Kit, however, the removal of the mould would only be a short-term fix if the source of moisture has not been prevented.

Damp Proof Course

Most modern properties are often built with a damp proof course installed, usually in the form of an impermeable plastic membrane, which is placed along a mortar line near the ground.  Older properties, however, are often built with no damp-proof course, or the original course has failed over the duration.

If your property is in need of damp proof course there are a number of methods that our team of qualified technicians can implement. We provide a variety of damp proofing systems to suit different property requirements, for example; a property constructed with stone may require an electro-osmosis system, whereas a property with brickwork construction may require a pressure injection.

DriWise Pressure Injection

Damp Proof Course

Pressure injections involve a water-based solution (DriWise) injected into brick, stonework and granite structures. The solution will form a barrier preventing the rise of capillary moisture into the wall. As with all our works, we offer a guarantee giving peace of mind should damp reoccur

Common questions I receive on a property survey include;

“Will the installation create a mess?” If the DPC is installed from the interior, a degree of mess will be made as plaster will need to be removed but don’t worry,  our technicians pride themselves on providing a thorough and clean service, minimising any mess or debris.  – Don’t take our word for it though See what our customers have to say. Our teams of technicians also have available what is known as an air scrubber to minimize the amount of dust that is in the property as a result of removing plaster from the walls.

“Do I have to move out whilst the works is undertaken?” – In most cases, you will not need to move out of the property, however, the level of work required in some instances may mean that some rooms may be out of use whilst the work is undertaken.

“How long will it take to dry?” – A damp wall will dry out in ideal conditions about 1 inch per month. following damp proofing works, redecoration should not be carried out until the plaster is dry, visibly and to the touch.

Electro-Osmosis System

Electro Osmosis System

The Electro-Osmosis System introduces a very small electric current into the wall just above the ground level. The current repels rising moisture back down the wall. As long as the charge is maintained the walls will remain dry and free of damp.

Damp Proofing Cost

“How much does damp proofing cost?” Is perhaps one of the most frequently asked question by homeowners with a damp issue.  The cost of damp proofing is subjective to a number of variables including; property size, location and accessibility.  individual property.

The type of damp proofing system to be installed also has an effect on cost. Physically replacing the injected damp proof course is a very difficult process that would definitely involve large amounts of structural work taking place – for that reason, the most common and cost effective treatment for rising damp is to install what is known as a chemical damp proof course (See our DriWise system above) or dependent on the situation an electro osmotic damp proofing system.

If you are looking to the work out the potential cost implications for your rising damp problem, give one of our customer service team a call on 0800 288 8660 or simply request a survey. A visit from one of our experienced and qualified surveyors will allow you to obtain an accurate costing for solving your damp problem.