01768868783      |      21 Friars Rise, Penrith, CA11 8DF       |      [email protected]

Rising and Penetrating Damp

Rising and penetrating damp are a common-place issue in properties,particularly old buildings and cellars. Penetrating damp is an identifying marker of an external issue, typically occuring from damage to the roof, window and door reveals, lead flashing, chimney stacks, external render defects or mortar joints. Wheras rising damp is the result of an absent, breached or decayed damp proof course (DPC) allowing hydroscopic pressure to cause ingress from the ground level up. Modern houses will already have a DPC installed as a specification, however they can become damaged or ‘bridged’ over the course of time which could result in moisture ingress.


Rising Damp

Most buildings are porous to an extent and therefore have the capacity to absorb the moisture from the ground that surrounds them. The moisture content in soil will cause the foundations and contact brickwork to become wet, the drying action of the above parts of the wall then causes the moisture to be drawn upwards through the mortar by capillarity to evaporate through the surface leaving behind an unsightly tide mark along the lower part of the wall (typically no higher than 1 meter above ground level) and once the moisture begins to evaporate hydroscopic salts are present on the wall which in turn continuously draws moisture to the areas of the wall. As well as being unsightly, this causes irreparable damage to wall coverings and hydroscopic salts eventually causes the plaster to deteriorate.

Dampness in a property can cause an increase in moisture content of timber, creating ideal conditions for fungal growth and decay in timbers, commonly known as Dry Rot or Wet Rot.


Treatment and prevention of Rising Damp

There are 3 common methods implemented to treat and prevent Rising Damp. Chemical injection involves the existing plaster being removed up to 1 meter high along with skirting boards. Chemical DPC is then injected into the walls before re-instating the plaster and skirting boards. Alternatively, we often use the Delta Membrane system which is a cavity wall membrane that attaches to the wall before being plastered over. Another option is the Hey’di K-11 tanking system. All 3 treatments are highly effective at repairing or replacing damaged or non-existing DPC and carry the option to be guaranteed for up to 30 years


Penetrating Damp

Penetrating damp occurs when moisture enters the internal of the property through damage to the exterior. This could be caused by loose mortar joints, damage to lead flashing or chimney stacks. Leaking or blocked guttering and downspouts can also play a part in the ingress of moisture into a property. Similarly to Rising damp, the symptoms of penetrating damp commonly include stains on the areas affected and the presence of hydroscopic salts. Fungal decay may also occur to any timbers that have been exposed to moisture for a prolonged period of time. However, it is important to note that all 3 of these symptoms may not be present immediately but could change and develop over time.


Treatment and prevention of Penetrating Damp

When treating penetrating damp, first and foremost, the source of penetration needs to be located and repaired to prevent further ingress. The area then needs a time to dry out before the original plaster is removed and the wall underneath treated with anti-sulphate to neutralise the hydroscopic salts, before reinstating the plasterwork.


What to expect from a damp inspection or damp survey.

We provide a free, no obligation quotation for any queries relating to damp in your property. However, we do charge a market competitive fee for pre- purchase mortgage surveys.

We use top of the range equiptment that is calobrated after every use, to detect and assess levels of moisture in the property. If remedial works are required we would discuss the options available, providing a full insight into the different products and techniques we use to remedy the issue. We will issue you with a written, fully itemised quotation shortly after the site visit for you to discuss and compare before commiting to any works. All quoted works will be cost inclusive of a insurance backed guarantee. (This is optional at the clients discretion).





All types of damp issues

Treatment and prevention of Rising and Penetrating Damp