What is Damp Proof Course (DPC)?
Every house should have a protective damp proof course (DPC) layer in the walls of the property. That will help prevent moisture from move up the walls and into the living area from the ground below and surrounding the wall foundations. If your damp proof course DPC has failed or in some cases non-existent, then this is commonly referred to as rising damp.
What is rising damp?
If you live in a property with no Damp proof course layer, or DPC Injection to your walls then often ground water and in some cases drain water will be absorbed and rise up through a capillary action. This moisture then rises through the walls, mortar, plaster, concrete and over time will make your internal plaster pop or crumble, often creating damp spots on internal walls, and eventually lead to mould.
As Damp Specialist London the most common question we get asked is “what can you do to combat a rising damp problem?”
Damp Proof Courses (DPC) Slate or Black Plastic
When a house or extension is first built it is easy to combat potential “rising damp problem” and today forms part of standard building regs. A specialist damp proof layer is fitted to create barrier between the bricks at floor level, and the bricks above, stopping that moisture from climbing up the walls and entering the home.
With some old London properties, we find slate was used as a kind of DPC material, however today most modern builders will use durable water-resistant material and most widely available method these days is a specialist damp proof plastic membrane.
You can find your DPC by taking a look at your external wall. Look down at ground level and look up about 6 inches or so up the wall. Somewhere around here you will see a thin black line of either slate or plastic running horizontally across the brick work. This is your DPC. Before any damp proofing treatments are conducted our surveyors make a thorough check and survey around the whole of the house – water can be clever and enter in multi DPC failed areas.
Don’t think you have any DPC?
If your home was built ins the last 100, the majority of homes will have some form of DPC, however some DPC’s get damage, degrade or through vermin, building or home improvement work become susceptible to damp penetration.
Fortunately, with London Damp Specialists, we can fix failed DPC and take fast remedial actions to clear and future prevent rising damp penetration.
If you think that your home may have a damp problem and your home is showing signs of rising damp problems, then we recommend getting a survey from a damp expert.
How to fix rising damp and damaged DPC’s
There are now a wide array of different chemicals and specialist damp proofing gels that can be ‘injected’ into your walls to create a protective DPC. Often, this type of treatment is cheaper than installing a physical Damp proof course into an existing wall.
We offer a professional and qualified damp surveyor, with the right equipment to complete the initial assessment.
How much does DPC injection cost?
We often find we are working on a typical London Home, such as a Victorian mid terrace, in which a Damp proof Course DPC injection might cost as little £500- £800. As you might imagine prices can vary greatly considering the length of wall that required treatment, how far the damp has risen and any additional remedial action we need to take. The DPC injection process is simple, and once the job is done, it will last for many years.
If you would like to find out more or discuss your specific rising damp issues or failed damp proof course: 020 8528 3864 or [email protected]
Damp Survey Costs
Transparent pricing with no hidden fees for our independent, unbiased surveys.
Level 1
What’s included:
- Inspection of walls
- Inspection of floors
- Inspection of ceilings
- Leak inspection of drains and plumbing
- Damp information and prevention guide
Level 2
What’s included:
- Everything in Level 1
- Dry rot inspection
- Wet rot inspection
- Woodworm inspection
- Damp information and prevention guide
Level 3 (Most Popular)
What’s included:
- Everything in Level 1 & Level 2
- Thermal Imaging
- Air humidity testing
- HD boroscope camera
- Brickwork pointing inspection
- DPC inspection
- Ventilation flow test on extractor fans
- 4K drone imagery roof, chimney stack
and guttering inspection - Structural condition inspection
- Damp information and prevention guide
Survey Add Ons
Add On 1
Laboratory analysis Of plaster identifies hygroscopic salts such as chlorides and nitrates. which indicate whether damp is caused by rising groundwater or by plumbing leaks, This testing removes guesswork, allowing the exact source of moisture to be identified so the correct treatment is applied rather than carrying out unnecessary damp-proofing work.
Add On 2
qPCR DNA mould testing detects microscopic mould spores that are invisible during a normal inspection and van remain hidden behind walls, floors. or inside building rkaterials. It identifies the exact mould species present and the contamination level, allowing hidden mould problems to be confirrned and properly treated before they affect the property or occupants’ health.
Qualifications: All our surveyors are PCA and CSRT qualified for remedial treatments and also CSSW qualified for structural waterproofing.
Next day report: You will receive the report within 24 hours of the inspection taking place.
The survey fee will be deducted from the cost of any recommended repairs.
These are the tools we use
A damp meter
A damp meter is a diagnostic tool used to detect and measure moisture levels within building materials such as plaster, brick, timber, and concrete.
Borescope camera
borescope camera is a small inspection camera attached to a flexible semi-rigid cable that allows you to see inside areas that are otherwise inaccessible.
Inspection Drone
A drone is a remotely operated aerial device equipped with a camera that allows visual inspection from above without the need for scaffolding or ladder.
Air Humidity Sensor
Air humidity sensor measures the amount of moisture present in the air, expressed as relative humidity (RH) in percentage. It helps determine whether indoor conditions are contributing to condensation, mould growth, or damp-related issues.
Thermal Imaging Camera
A thermal imaging camera detects temperature differences on surfaces by using infrared technology to produce a heat map image. In damp investigations, it helps identify cold spots, moisture intrusion, insulation defects, thermal bridging and leaks.
Air Flow Ventilation Detector
An air flow ventilation detector measures the movement and volume of air passing through vents, extractor fans, and air bricks. It confirms whether ventilation systems are working properly and achieving adequate air changes within a room. Poor airflow leads to trapped moisture, high humidity, condensation on cold surfaces, and ultimately mould growth.
Mould Swab Test Kit
A mould swab test is carried out to confirm the presence of hidden mould growth and identify the specific species involved. Surface mould is not always visible, especially behind furniture, inside cavities, or within ventilation systems. Laboratory analysis of a swab sample determines whether active mould spores are present and what type they are, which helps assess potential health risks and decide the correct remediation approach rather than relying on visual assumption alone.
Plaster Salt Analysis Lab
Laboratory analysis of plaster is used to identify the type of salts present within the material, typically chlorides and nitrates. The presence and concentration of these salts help determine whether the moisture source is consistent with rising damp, ground contamination, or another forms [sic] of water ingress. such as mains water leak, This removes guesswork and prevents misdiagnosis, ensuring the correct remedial treatment is specified rather than applying unnecessary or ineffective solutions.
