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Rising Damp Control

Rising Damp Treatment

Cost Effective Damp-proofing in the North Wales, Chester & The Wirral Regions

Damp-proofing is often required in older properties in North Wales, Chester & The Wirral.  They may have been built without a physical damp-proof course (such as in stone built cottages etc) or the existing damp-proof course has failed due to bridging either internally or externally.

What is Rising Damp?

Rising damp is distinct from other forms of dampness and moisture, such as rain penetration and condensation, which require different solutions.  This damp problem is not limited to the UK, but is found throughout the world where there is moisture present in the earth below a building.

Rising damp is the upward movement of moisture through walls, and sometimes floors, by capillary action from below the ground. It occurs to the walls at ground floor level in lower portions of external and interior partition walls. The height to which rising damp will rise depends on the size of the capillaries within the building material, the amount of moisture in the ground (water table level) and the evaporation rate from either face of the wall surface. As a general rule, the smaller the capillaries of the structure, the higher the water will rise up the walls. However, the height of rising damp usually does not extend much further than approximately 1 metre above ground level.

Modern buildings, in Great Britain, prevent rising damp with a system of damp proofing barriers – a physical damp- proof course (DPC) has been required in walls since 1875 and damp proof membranes (DPM) in floors from the 1960’s. Most old buildings lack these and therefore rising damp can occur.  However, the presence of a damp course does not guarantee that rising damp will not occur.  If the continuous run of the dpc has been bridged or broken then dampness can appear in the wall.

Rising Damp Symptoms

Rising damp is fairly slow to develop and may be present for several years before any symptoms become apparent.  Eventually it may show as a tide-like damp stain on the wall with little or no damage above; but below, the paint may be blistering, wallpaper stained and peeling, the wall plaster damaged and skirting boards showing signs of timber decay. External signs of rising damp are darkening of the lower brickwork, white salt marks and even spalled (damaged) brickwork. Floors can display moist damp patches and damp staining.

Rising Damp Survey

Before considering the installation of a chemical damp proof course to cure rising damp, the Damp Aid North Wales specialist surveyor will carry out a damp survey to assess the damp problem and ascertain the exact cause of the dampness or moisture and establish the need for rising damp treatment.  Factors such as high external ground levels, poor surface drainage, defective gutters and down pipes can all cause the damp proof course to be bridged, leading to the symptoms of rising damp.  By addressing any or all of these defects and allowing the damp wall to dry out naturally, then in most cases the cost for a new chemical damp- proof injection or damp- proof course is avoided. Only as a last resort, is a chemical damp- proof course installed.

Should the Damp Aid North Wales surveyor, after carrying out a thorough inspection both internally and externally, and eliminating all other causes such as condensation and penetrating damp, diagnose rising damp, then he will assess the extent of the dampness and the need for replastering.  A damp report and/or damp quotation will be provided outlining the most cost effective solution or remedial treatment to the damp problem.  The pre-purchase damp survey & report issued will satisfy the mortgage lenders.

Rising Damp Treatment

As rising damp experts we will carry out the most appropriate treatment to cure the rising damp problem.

Installing a chemical damp- proof course (dpc) involves the drilling of the brickwork / mortar to pre-determined depths of external and/or internal walls and then injecting the damp proof course fluid.  A chemical damp- proof course provides an impermeable barrier at low level in the structure to prevent further rising damp occurring. This is the most common form of specialist damp proofing used nowadays.
(The BRE – Building Research Establishment – gives advice to consider only methods of damp proofing that have been awarded an Agrément or other third-party certificate. Chemical damp proof injection has an Agrément certificate and is the most cost effective method of providing a damp proof course)

The Cost of Treating Rising Damp

We are often asked – How much does rising damp treatment cost / How much does a damp proof course cost?

The cost of treating rising damp or the cost of a damp proof course (damp proofing) varies from property to property.  Firstly, a damp survey has to be carried out by a fully qualified CSRT damp proof surveyor to correctly identify the dampness and determine if it really is rising damp in need of damp-proof treatment.  Other sources of moisture have to be eliminated, such as penetrating damp, condensation, plumbing leaks etc. before even considering if rising damp is present in a property.  The construction of the building also has to be taken into consideration.

Therefore there is no standard cost for damp proofing a house in North Wales, as each individual property is different from the next.  Damp proofing prices differ between each individual timber and damp proofing remedial company and the damp proofing system used. Many North Wales & Chester properties we have surveyed resulted in no remedial damp-proofing work being required therefore substantial savings were made compared to the average cost of damp-proofing and woodworm treatment to a house which can easily amount to thousands of pounds.

Damp-Proof Re-plastering

The effects of rising damp will usually damage internal plaster and deposit hygroscopic salts, which absorb moisture on days of high humidity.  Replastering is normally required to remove all salt contaminated and damaged plaster.  Visibly unaffected plaster may be left to see if it dries following the damp proof course treatment.

Re-plastering usually means that wall plaster affected by damp has to be removed to a height of approximately 1.2m and then replaced with a waterproof render before applying a skim finish ready for decorating.

Damp Aid North Wales can submit a estimate to carry out this associated work but we leave the option open for our clients to use their own builders to undertake the re plastering in accordance with our specifications in order to reduce costs. Even if the re plastering is not carried out by Damp Aid North Wales we will still provide a 10 year insured guarantee against rising damp which you may require for you Building Society or Bank for mortgage purposes.

All guarantees are backed by a 10 year insurance scheme and these insured guarantees give you peace of mind in the unlikely event that Damp Aid North Wales ceases to trade so that your damp-proofing guarantee will still be honoured.  Insurance backed guarantees are issued in association with the Guarantee Protection Trust who provide the only insured guarantees in the damp-proofing and timber treatment industry which are authorised by the Financial Services Authority. These guarantees are only available to damp-proofing contactors who are members of the BWPDA and Property Care Association (PCA) of which Damp Aid North Wales is a member company.If you have any questions or require advise, please contact us on (Wales) 01492 535305, (Chester) 01244 490341, (Wirral) 0151 959 0086, email us at:  info@dampaidnorthwales.co.uk or fill in our enquiry form.