Damp & Mould: 5 Worst Case Scenarios for London Property Owners
London sits on a bed of clay called the Thames Valley Basin and that means a high level of water retention, which can lead to serious damage to a building. In this short article, we present a few worst-case scenarios that London homeowners might face.
- Missing roof tiles – In the event a storm lifts a few roof tiles are lifted by gale-force winds, this could allow a lot of rainwater into the internal roof structure. Imagine going away for a few weeks at the same time the roof develops a serious leak, you would return to a nightmare scenario with ceilings collapsing and plaster falling off walls. This is one reason to arrange for a roof inspection every few months; early detection can literally save you a fortune in repair bills.
- Floods – Imagine a burst water pipe in the upstairs bathroom and you are away for a few days! The nearby river bursts its banks and suddenly, you are faced with a metre of water! While these things do not bear thinking about, they do happen. Of course, your home insurance should cover flood damage, you should read the small print, just to make sure. Time is of the essence when it comes to water damage and all damaged furniture should be removed.
- Bridging the damp proof course – The DPC is a crucial component and some homeowners build an extension without giving this a thought. If the extension you built bridges the existing DPC, damp can rise up the walls and that will spread to all parts of the house. Even a piece of wood placed against the external wall can allow moisture to bypass the DPC and that can be disastrous.
- Black mould infestation – If a property is unoccupied for a few months, mould can spread quickly if damp is present, and black mould is the most dangerous of all forms of mould, which can be fatal with prolonged exposure. The building would need to be evacuated and all furniture removed before tackling the mould. Contact a mould specialist and let the expert assess the situation and recommend a solution.
- Wet and dry rot infestation – Again, this would probably occur in an empty property and it doesn’t take long for it to spread to all parts of the building. The roof joists and rafters are ideal places for mould to take hold, while floorboards are another key component where rot and mould can form. If you are thinking of buying a London property, it makes total sense to book an independent damp survey to discover whether or not the building has damp or mould issues.
At London Damp Specialists, we provide professional damp surveys by certified inspectors; call us on 020 7205 4886 or leave your contact details in the online form on this website. You will receive a detailed report in your inbox within one day of the survey, plus we are happy to quote for damp-proofing work. Although we do not do damp-proofing work, we do have a close relationship with a top damp-proofing contractor that covers all areas of London.
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:
- 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
- Inspection of walls
- Inspection of floors
- Inspection of ceilings
- Leak inspection of drains and plumbing
- Dry rot inspection
- Wet rot inspection
- Woodworm 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.
These are the tools we use
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.
Drone Inspection
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 Lab Swab Testing
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.
Lab Analysis of Plaster
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.
