WELCOME TO Derry Damp Co

Our panel of damp proofing experts Cover Derry & surrounding areas













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If you have a property which has signs of damp then you already know how unslightly it can be. But in many instances damp triggers mould growth which can also effect your respiratory and immune system. Speak to one our specialists for damp proofing in Derry today.

Diagnosing Damp in Your Home

If the damp is left untreated the issues become much worse, in some cases causing structural damage leading to significant repair costs with builders and surveyors. When left untreated, the unfortunate fact is that the damp invariably becomes more severe and will eventually cause structural damage leading to higher repair costs in the long run.

When diagnosed promptly the underlying causes of the damp in your home can be addressed and treated both effectively and cost effectively. When you first notice you’ve got a damp problem, that’s the right time to take action and call a damp proofing specialist. Derry Damp Co members are a time served local damp proofers specialising in all aspects of damp treatment and remedial repair works.

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The major 3 causes of damp are:

Causes of Damp in Derry

Penetrating damp
Rising damp

Learn More About Each Type of damp found in properties throughout the UK in the handy table below:

Penetrating Damp

Where penetrating damp is below the high external ground level we would carry out a process called tanking, this is applied internally at the bottom of the wall as part of the rising damp treatment.
Where penetrating damp occurs above the external ground level it is often the case that we would apply a water repellent called SecoTherm, to the outside brickwork, this prevents rain penetration into the brickwork and the chemical structure allows any moisture present in the wall to evaporate into the atmosphere. (A breathable membrane.) Other treatments include repairing damaged brickwork, guttering, downpipes and roofing repairs. 

Rising damp

When treating rising damp in Derry all work undertaken by our panel of damp proofing experts is carried out in accordance with British Standards BS-6576-1985, entitled, The Installation of a Chemical Damp Proof Course.

If required, and the new damp course needs to be injected from inside of the property plaster would be removed from the wall to a minimum height of 1.00 metre from the internal floor and a chemical damp proof course would be installed, if possible and the injection can be carried out externally this makes the job cheaper in terms of its cost to the homeowner as remedial repair works such as re plastering will not be required. Wherever possible damp proofing professionals inject new courses externally but on the occasion this is not possible will explain why to the homeowner.

Brickwork would be treated with an anti-sulphate solution to stabilise the salts ensuring no further salt contamination to the new plaster, after which a lightweight renovating plaster will be applied to the brickwork and then the wall will be skim plaster finished.


Sometimes the treatment for condensation in Derry can be as simple as opening a window or turning on an extractor fan when cooking, but for more serious condensation problems professional solutions may be needed. Derry Damp Co members are passionate about providing good indoor air quality to everyone, which is why we offer a wide and varied range of eco-friendly and innovative ventilation systems, designed to deliver homes with fresh, filtered air. After completing a free, no obligation survey of your property our damp proofing specialists will be able to advise on the best course of action to rid your Derry home of condensation, on many occasions  find that simple lifestyle changes are all that is required for treatment, and as such there is no cost to the homeowner, on other occasions with more sever cases professional services are required and quoted for.

If a house is suffering from a damp problem in Derry, it means there’s unwanted moisture. It’s usually found in the walls, ceilings or floors.

A damp problem can occur when water or moisture works its way into your house. This can simply be as a result of condensation around windows, but there can be plenty of other causes.

There are a number of tell-tale signs that suggest dampness in a house.

These signs of damp include:

  • A distinctive musty smell
  • The appearance of mould or mildew on walls, floors or ceilings
  • Walls, floors or ceilings that feel cold or wet
  • Water droplets on walls
  • Dark or discoloured patches on walls or plaster
  • Lifting or peeling wallpaper from moisture in the walls
  • Excessive condensation on windows, not just during the winter
  • Rotting woodwork like skirting boards
signs of damp in harltpeool properties

Environmental & Structural Factors

Damp is the result of environmental and structural factors. Houses built on a flood plain must have effective damp coursing or basement tanking, due to the fact the lower floors of such a property in most cases extend below the water table. Victorian propertie, were built to different standards than today’s and are vulnerable to penetrating and rising damp. In many instances, insensitive alteration has increased condensation troubles, too.

Britain’s weather patterns are clearly changing, with hotter summers and wetter, wilder winters. Flooding and torrential rain has become commonplace, so if your property predates the 21st century you probably need to revise your damp proofing. Derry Damp Co members specialise in conservation damp proofing, and always recommend the proper treatment which respects your property’s heritage.


Thank you for considering us. We are able to assist much faster if you fill in the contact form here on the website, our customer service assistant will forward your form straight through to a member of our panel of damp proofing experts who will call you straight back to arrange a quote.

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Contact Derry Damp Co

In some cases damp problems in a property can be more complex with different causes resulting in extensive damage. The fastest and easiest way forward is to get in touch with a specialist damp proofing company with the experience and expertise required to effectively diagnose and treat the problems at hand. Derry Damp Co members deliver a 100% diagnosis and cure rate for any damp problem in your home or business premises.