Rising Damp

Rising Damp Treatment

Treatment for Rising Damp

Rentokil Property Care has a team of rising damp specialists ready to provide effective remedial rising damp treatment. Located across the country, we offer rising damp treatment to homes and businesses of all age and sizes.

Do you need rising damp treatment? Call Property Care free on 0800 0121 437 to arrange a rising damp survey.

What is Rising Damp?

Rising Damp is the term used to describe dampness in a wall structure, where there is higher moisture content at the base of the wall, which rises further up the wall.

How To Identify Rising Damp

The problem of rising damp can be identified by a number of different signs, which include:

  • Damaged internal decoration – damp, discoloured tidemarks on internal decoration.
    Image of rising damp - a wall in need of rising damp treatment | Rentokil Property Care
  • Damaged Plaster - blistering, salting and disintegration
  • Rotting skirting boards, floor timbers – wet rot decay
  • Localised dampness – dampness on walls rarely exceeds one metre above ground level, but may go much higher in extreme cases

What Causes Rising Damp?

The main causes of rising damp are:

  • Failure of an existing damp proof course
  • No damp proof course at all
  • High external ground bridging an existing damp proof course
  • Internal plaster bridging an existing damp proof course
  • Bridging of damp proof course due to a build up of rubble inside a cavity wall
  • Residual dampness at the base of the wall following a previous penetrating damp problem
  • Condensation at the base of a wall due to poor air circulation
  • Leaking water pipes at the base of a wall

Due to the complex nature of rising damp, its identification needs to be carried out by an industry qualified surveyor.

Rentokil’s team of surveyors and rising damp specialists are professionally trained. They have over 80 years experience in the field of remedial damp treatment.

Rising Damp Survey by Rentokil

A qualified Rentokil surveyor will carry out a thorough inspection of your property to establish the need for any rising damp treatment.
A rising damp survey includes:

  • External inspection – to look for defects that may relate to the existing problem or cause damp problems in the future
  • Visual inspection of all internal ground floor walls – walls will be scanned with a resistance moisture meter. Where visible damage to decorations or higher levels of moisture in the plaster is identified, a more detailed inspection will be carried out.
  • Checking floorboards – if the ground floor is of timber construction, floorboards will be lifted to check if timber decay is occurring to the wall plate and joists beneath the floor surface.
  • Calcium carbide tests will be taken to identify a dampness profile. This entails drilling into the wall to extract mortar samples for testing on site.

Once dampness has been identified above the normal threshold, the surveyor will make recommendations on the most appropriate rising damp treatment.

Recommendations may vary depending on our customer’s requirements. A Rentokil surveyor will always try to adapt the specifications to solve the problem and at the same time match our customer’s needs.

Rising Damp Treatment

Rentokil’s rising damp specialists will carry out the most appropriate treatment for your property, which will include the installation of a damp proof course. A low odour water based silicone injection system is generally regarded as the most effective type of damp proof course.

Installation of damp proof course

Dependant on the thickness of walls, holes are drilled in the mortar / brick of external and internal walls to a pre-determined depth and at the correct level and spacing between holes. These holes are then injected with damp proofing fluid to reduce the movement of water through the capillaries.

Following the insertion of a damp proof course it is common for re-plastering to be required. Any new plastering has to prevent dampness and salts present within the wall migrating onto the internal wall finish.

Re-plastering

The most common approach to re-plastering is using a dense sand and cement render as a backing coat incorporating a waterproof additive. Once dry, a gypsum skim coat is applied to give a smooth finish.

When the existing plaster is removed, there may be a lot of dust. We advise that adequate steps are taken to remove or cover furnishing for protection.

Rising Damp Treatments information leaflet - please download for more information.

Rentokil’s rising damp treatment is covered by a 30-year guarantee, which can be passed on to future owners of the property. We can also offer insurance to cover untreated areas for timber and damp problems by taking out a Rentokil Insurance policy.

Do you suspect rising damp? Contact Rentokil Property Care to arrange a rising damp survey or to discuss our rising damp treatment.