Damp Proofing FAQ

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Damp Proofing FAQ

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Affordable Expert Advice & Repairs Across Scotland and the North of England

Q: What is damp?

A: Damp is a common problem, that properties across the UK will suffer from at some stage. If untreated, damp can be extremely damaging to the structure and fabric of your home.

If you are unsure what causes structural dampness, it is the presence of unwanted moisture in the structure of a building. Dampness is cause by either the result of penetration from outside or damp created within the property. There are a number of terms which cover damp:
  • Plumbing Leaks
  • External Flooding
  • Below Ground Damp
damp marks on the wall

Q: Why Does Damp Occur?

A: There are a number of ways damp can be caused, this includes condensation, rain penetration, and rising damp. If you are not sure whether you have damp in your home or not? Here are some symptoms that may arise:
  • Dampness and unwanted moisture, in some cases, causes the production of fungi in wood. This type of damage causes rot and mould. The worst cases of damp can lead to sick building syndrome.
  • Damp can cause plaster and paint to deteriorate. If the walls in a damp area are wallpapered, you may see the paper begin to loosen.
  • Damp can cause stains to form. These water stains can from the drying out of the fabric or staining from contaminates in the structure.
A high proportion of damp problems in buildings is caused by condensation, rain penetration and rising damp. What are the symptoms of damp? In most cases, dampness is the cause of secondary damage to a building like defective roof coverings or rainwater gutters and downpipes.

Q: Where can dampness be found?

A: Dampness can be found anywhere in a building and can affect all types of properties, old and new. It is important that when dampness is suspected an accurate diagnosis is required to determine the cause of the problem. Damp affects the fabric of the property and can also affect the air in the property creating high relative humidity which can lead to condensation and mould growth on surfaces. Damp can lead to several problems in a property including poor indoor air quality

Another sign that there is excessive dampness is mortar and bricks may crumble in the affected area. In extreme cases, render or plaster may fall away from the affected wall.

Q: How Can I Identify Dampness?

A: At Richardson and Starling, we use a wide range of instruments and techniques in conjunction with our experience to investigate and identify the presence of moisture in buildings. It is important that a professional surveyor assesses your property for damp.

Damp can cause problems to the building and its inhabitants, therefore this role requires competence and experience from the person undertaking the damp investigation. At Richardson and Starling our damp specialists are fully trained and only use professional equipment to diagnose the type of damp.

It is important that the type of damp is correctly diagnosed as this will determine the appropriate specification to resolve the damp problem. Rising damp is often mistaken for other forms of damp, which means the wrong treatment is applied. By using one of our experienced surveyors, they will identify the damp issues and give a report and specification to deal with the problem.

Q: What is a damp-proof course?

A: If you are living in Scotland or the UK, then it is vital that your property has a damp proofed structure that will protect the building from problems such as penetrating damp, rising damp and below ground damp.

A Damp Proofing system is a type of moisture control barrier that can be applied to walls and floors to prevent moisture from passing into the interior spaces. Damp is extremely common in the UK and it is one of the most required property care treatments.

Concrete and masonry walls will normally allow moisture to pass through so a horizontal and vertical damp proof barrier is required at the appropriate position. Our Richardson and Starling teams can fit a damp proofing course (DPC) damp proofing system that is appropriate for your property:
  •  A damp-proof course (DPC) is a barrier which can be inserted through a structure to stop capillary action. If capillary action isn’t prevented, then there is potential for rising damp. A DPC layer is usually fitted in all masonry walls, regardless if the wall is a load bearing wall or a partition wall.
  • A damp-proof membrane (DPM) is a membrane material applied to prevent moisture transmission.
  • Integral damp proofing in concrete involves adding waterproofers to the concrete mix to make the concrete itself moisture resistant.
  • Renders and surface coating with thin waterproof materials for resistance to non-pressurized moisture such as rain water.
  • Cavity wall construction is where the interior walls are separated from the exterior walls by a cavity.
damp proofing works in progress

Q: What method do you use for installing a damp proof course?

A: There are various methods of installing a reliable, remedial damp proof course:
  • Most commonly a chemical injected DPC is placed using a specially formulated cream or water based product. The wall is drilled at the appropriate level by a member of our Richardson and Staling team and the chemical is inserted into the holes.
  • Mortar injection DPC is used mostly in random rubble stone walls. Our technicians will drill holes in the wall and apply a specially formulated cement based mortar.
  • Another way to apply a DPC is through an electro-osmosis system. This system uses an electric charge which is installed to the wall through wires and earthed to the ground to pull the capillary action back into the ground.

Q: Why does the plaster have to be removed during damp proof course works?

A: Plaster must be removed during the damp proofing process as rising damp coming from the ground brings moisture up the wall. Along with moisture, it will bring hygroscopic salts, nitrates, and chlorides.
Hygroscopic salts attract moisture from the atmosphere. These salts will contaminate the plaster inside the property and even after a remedial DPC has been inserted the salt contaminated plaster can still become damp. This is why it is vital that contaminated plaster is stripped and replaced during the treatment.

Our specialists will only remove what is required and in most cases this will be one metre above the floor level. The reason why one metre is removed is because damp can rise to one metre depending on the site construction. Each case of damp is different and the repair will be determined to suit the property.
damp proofing - before and after

Q: When can I carry out redecoration after the damp proof course?

A: The first stage of decoration should be applied once the plaster has dried. After this, you can apply a water-based emulsion (strictly not vinyl paint or wallpaper applied).

 It is important that you use a water-based paint as it allows the wall to breathe and dry out. Rising damp affected walls can take up to 6 months to dry out for a 150mm thick wall and may even be longer as it depends on the thickness of the wall and its construction.

Q: What is a damp-proof membrane?

A: To stop damp penetrating your property it is important that the outside of the property is waterproof to stop damp getting in and causing damage. The masonry or render should prevent water penetration and should be repaired if this is not working. Special water repellents can also be used to stop rainwater penetrating the external walls if required. The ground below your floor should have a damp proof membrane to stop damp coming from the ground and a damp proof membrane can be applied internally to walls to stop damp getting to your plaster and decoration. These membranes are also used on wall areas that are below ground level that can be affected by penetrating damp from the ground.

Q: Is damp-proofing work guaranteed, covered by insurance?

A: Having property care completed in your home can be extremely stressful, therefore, our customers can take peace of mind that your damp proof course will be installed efficiently and correctly.
We believe that every property care specialist should give their customers long term guarantees. The length of the guarantee is detailed in our report and is automatically transferred to new owners. We are confident in the standard of our work that we are pleased to issue a guarantee you can trust.

Richardson and Starling Guarantees
30-year guarantee for the treatment of Rising Damp, Dry and Wet rot repairs and woodworm treatment.
10-year guarantee for basement waterproofing
5 year guarantee on Timber window repairs
We can also offer an independent insurance backed guarantee should the client require this.
30 year guarantee on damp proofing works

Q: How much roughly does damp proofing cost?

A: This is a question that we are often asked by our clients. As every property and damp problem is different the cost for damp proofing cannot be given until our surveyor has investigated the extent of the problem. Once our surveyor has completed your property survey we will issue a report, specification and quotation for the remedial work.

What Services Do We Supply?
  • Damp Property Surveys
  • Damp Proofing Specialist
  • Rising Damp Treatment
  • Condensation Control
  • Basement Waterproofing
  • Dry/Wet rot Treatment
  • Woodworm Treatment
At Richardson and Starling, we are leaders in property care and repair services. With over eight decades experience there isn’t a property care problem that we cannot fix! We provide all of the services above in 12 branches accross Scotland and The North of England.

Call a member of our Damp Proofing team today and they will arrange a time to survey your property that suits you or your tenants.
Expert Advice & Repairs Across Scotland and the North of England
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