Useful Links

020 8945 5547 info@independentdampsurvey.com
Request a Survey

Roof Leak & Penetrating Damp Survey in Streatham (SW16)

Back to all Case Studies
Roof Leak & Penetrating Damp Survey in Streatham (SW16)

A Level 2 damp survey was conducted on a residential property in Streatham (SW16). The property owner instructed an independent investigation after spotting water marks near the loft space. The objective was to obtain an impartial diagnostic appraisal of the internal structure and external roof covering.

About the Issue

Attention was drawn to a single damp spot on the bedroom ceiling and visible staining around an adjoining skylight frame. The homeowner was anxious that water was migrating through internal walls or leaking from concealed plumbing runs.

The Challenge

The surveyor conducted a Level 2 damp survey, systematically testing living areas, subfloors, wall bases and ceilings using visual checks and electronic moisture testing tools.

The diagnostic process yielded key physical findings:

  • Wall and floor moisture testing registered zero abnormal readings across all living areas, ruling out rising damp and lateral water penetration.
  • Plumbing inspections confirmed no active internal pipe leaks were present.
  • Physical testing identified one localised damp spot on the bedroom ceiling, consistent with rainwater tracking down through the roof space.
  • Inspection around the skylight revealed staining linked to defective surrounding seals and flashings.

Exterior checks showed the roof was in worn overall condition. Rainwater was entering through cracked and worn render, poorly sealed roof details and defective tiles, confirming that the ceiling moisture was caused by roof penetration.

The Solution

The report provided a clear remedial roadmap focused on external weatherproofing and internal drying:

  • Engage a qualified roofer to repair or replace loose, cracked, or poorly sealed roof tiles and make cracked render weather-tight.
  • Overhaul flashings, junctions and seals surrounding the skylight to guarantee complete watertightness.
  • Permit damp internal plasterboard and ceiling sections to dry out thoroughly once external fixes are completed.
  • Apply a stain block and redecorate minor stains, replacing localised plasterboard only if moisture has softened the material.

The Outcome

The homeowner achieved complete peace of mind knowing their walls, floors and plumbing were fully sound. Armed with an independent diagnostic report, they avoided unneeded internal treatments and focused their resources on targeted roof maintenance.

Why This Case Matters

A single ceiling water mark can easily be misdiagnosed by contractors eager to sell whole-house damp treatments. Independent damp specialists trace moisture to its exact physical origin, protecting property owners from over-engineered contractor solutions.

FAQs
How was the ceiling dampness diagnosed as a roof leak?

The location and pattern of the damp spot, combined with dry wall/floor readings and visible exterior tile and render defects directly above, confirmed rainwater entry from the roof.

What works are required around the skylight?

A roofing contractor must inspect and repair the surrounding flashings and seals to ensure rainwater cannot enter around the skylight frame.

What should be done to internal ceilings after the roof is fixed?

Affected areas must dry fully first. Minor staining can be covered with a stain blocker before repainting, while softened plasterboard should be spot-replaced.

Gain complete confidence in your building’s health with an independent diagnostic survey.

Share this project
Back to all Case Studies

Damp Survey Costs

Transparent pricing with no hidden fees for our independent, unbiased surveys.

Level 1

Level 1

£199 + VAT

What’s included:

  • Inspection of walls
  • Inspection of floors
  • Inspection of ceilings
  • Leak inspection of drains and plumbing
  • Damp information and prevention guide
Book Now
Level 2

Level 2

£299 + VAT

What’s included:

  • Everything in Level 1
  • Dry rot inspection
  • Wet rot inspection
  • Woodworm inspection
  • Damp information and prevention guide
Book Now
Most Popular
Level 3

Level 3 (Most Popular)

£399 + VAT

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
Book Now

 Survey Add Ons

Add On 1

£299 + VAT
Lab Analysis Of Plaster

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 to Survey

Add On 2

£299 + VAT
Mould Lab Swab Testing, qPCR on DNA

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.

Add to Survey

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

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

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

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

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

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

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

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

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.

Professional Survey Equipment

Surface Damp Meter

Purpose:

Takes comparative surface moisture readings across accessible walls, floors, ceilings and building joinery.

Common Uses / Notes:

Maps surface moisture profiles to help identify rising damp, penetrating damp, condensation, or active plumbing leaks.

Deep-Penetration Damp Meter

Purpose:

Detects moisture changes deep below the immediate surface of structural materials without destruction.

Common Uses / Notes:

Evaluates dampness within wall cores, beneath floorboards, inside subfloors and behind finishes without removing plaster.

Non-Invasive Moisture Scanner

Purpose:

Scans surface planes non-invasively without inserting pins or probes into decorated finishes.

Common Uses / Notes:

Checks decorated walls, tiled surfaces and delicate floor coverings to trace sub-surface water migration non-destructively.

HD Borescope Inspection Camera

Purpose:

Provides high-definition visual examination inside enclosed, narrow, or inaccessible building cavities.

Common Uses / Notes:

Inspects subfloor voids, wall cavities, dry lining and enclosed pipework to locate leaks and defects with minimal disruption.

4K Inspection Drone

Purpose:

Captures high-resolution imagery and video of high-level external structures and rooflines.

Common Uses / Notes:

Inspects roof tiles, chimney stacks, lead flashing, parapet walls, valleys and gutters to locate water ingress sources.

Air Humidity Sensor

Purpose:

Measures ambient air temperature and relative humidity (%RH) levels within living areas.

Common Uses / Notes:

Determines whether atmospheric moisture, cold bridging, or insufficient ventilation supports surface condensation and mould growth.

Thermal Imaging Camera

Purpose:

Visualises surface temperature differentials across walls, ceilings and floors.

Common Uses / Notes:

Detects cold spots, missing insulation, thermal bridges, evaporative cooling zones and concealed water leaks.

Airflow & Ventilation Detector

Purpose:

Measures volumetric air extraction performance (L/s or m3/h) of mechanical extractor fans.

Common Uses / Notes:

Tests kitchen, bathroom and utility fans to verify compliance with UK Building Regulations Part F and control condensation.

Gas Screening Instrument

Purpose:

Screens indoor environments for sewer gas intrusion, combustible gases and combustion concerns.

Common Uses / Notes:

Traces foul odours, soil stack leaks and sewer gases (H2S, NH3, CH4, CO, O2). Does not replace Gas Safe registered safety checks.

Chemical Vapour Detector

Purpose:

Screens air for Volatile Organic Compounds (TVOC/VOC) and chemical substances like formaldehyde (HCHO).

Common Uses / Notes:

Investigates unexplained chemical odours, building material off-gassing, post-flood air safety and indoor air quality.

Airborne Particle Detector

Purpose:

Measures airborne particulate concentrations across precise micron size ranges (PM1.0, PM2.5, PM10).

Common Uses / Notes:

Assesses fine dust, smoke, airborne matter and environmental air quality following water damage or mould outbreaks.

Electrical Socket & RCD Tester

Purpose:

Provides basic safety and protective circuit screening in areas affected by dampness.

Common Uses / Notes:

Identifies socket wiring faults, tests RCD trip functions and checks AC voltage in wet areas. Does not replace an EICR.

Survey Levels & Package Specifications

Level 1

Standard Damp Survey

Standard price: £299 + VAT

Promotional Price: £199 + VAT (Limited Time Offer)

Offer ends in--Days--Hours--Mins--Secs

The Level 1 service is a straightforward inspection of the main accessible areas for visible damp, leaks and moisture-related defects.

Equipment provided

  • Surface damp meter

Inspection coverage

  • Accessible walls
  • Accessible floors
  • Accessible ceilings
  • Visible drains and plumbing for signs of leakage
  • Damp information and prevention guide

Who should choose Level 1?

Level 1 is suitable for relatively simple concerns, including a visible damp patch, suspected rising damp, minor staining or a general moisture check.
It is intended for customers who require a basic inspection using a damp meter and do not need deeper moisture testing, thermal imaging, timber investigation, ventilation measurements or roof-level drone imagery.

Level 2

Detailed Damp & Timber Survey

Standard price: £399 + VAT

Promotional Price: £299 + VAT (Limited Time Offer)

Offer ends in--Days--Hours--Mins--Secs

Level 2 contains the accessible checks included with Level 1 and adds deeper moisture detection and inspections for common timber defects.

Equipment provided

  • Surface damp meter
  • Deep-penetration moisture meter
  • Non-invasive moisture scanner

Inspection coverage

  • Walls, floors and ceilings
  • Visible drains and plumbing for signs of leakage
  • Wet rot
  • Dry rot
  • Woodworm
  • Timber decay
  • Deeper moisture investigation
  • Non-invasive scanning of accessible floor and subfloor areas
  • Damp information and prevention guide

Who should choose Level 2?

This survey is appropriate when moisture may be concealed behind finishes or within building materials. It is also suitable when there are concerns about wet rot, dry rot, woodworm or general timber deterioration.

Level 2 is a useful choice for buyers and sellers who want a more comprehensive inspection than the basic Level 1 service but do not require the complete advanced equipment package or drone inspection included with Level 3.

Level 3

Comprehensive Damp Survey

Standard price: £499+ VAT

Promotional Price: £399 + VAT (Limited Time Offer)

Offer ends in--Days--Hours--Mins--Secs

Level 3 is our most extensive standard survey. It incorporates the checks offered by Levels 1 and 2 and adds thermal, environmental, ventilation, concealed-area and high-level external inspections.

Equipment provided

  • Surface damp meter
  • Deep-penetration moisture meter
  • Non-invasive moisture scanner
  • Thermal imaging camera
  • Indoor humidity sensor
  • HD borescope
  • Airflow and ventilation tester
  • 4K drone
  • Socket and RCD circuit tester

Inspection coverage

  • Accessible walls, floors and ceilings
  • Visible drains and plumbing
  • Wet rot, dry rot and woodworm
  • Timber condition
  • Deep moisture detection
  • Accessible floor and subfloor scanning
  • Thermal imaging
  • Humidity measurement
  • Borescope inspection where appropriate access exists
  • Brick pointing
  • Visible damp-proof course
  • Extractor-fan airflow
  • Drone imagery where conditions permit
  • Roof coverings
  • Chimney stacks
  • Guttering
  • General visible structural condition
  • Basic socket and RCD checks

Who should choose Level 3?

Level 3 is designed for homebuyers, sellers and property owners who want the most detailed standard inspection. It is particularly useful when several possible causes must be considered, including roof defects, hidden leaks, dampness, mould, condensation, timber decay and inadequate ventilation.

Roof, chimney and gutter defects can be expensive and may be difficult to see from the ground. A drone inspection can identify visible high-level issues before a purchase is completed, potentially giving the buyer an opportunity to investigate costs or reconsider their position.

Even a comparatively small roof defect may cost more to correct than the price difference between survey levels. Water entering from above can also lead to plaster damage, internal staining, mould and timber decay if it is left unresolved.

Level 3 is therefore the most suitable option for customers who want detailed evidence before buying, selling, repairing or maintaining a property.

Optional Laboratory and Air-Quality Services

Add-On 1

Laboratory Testing of Plaster Samples

Price £299 + VAT

Small plaster samples are carefully taken from affected walls and submitted to an independent laboratory for salt analysis. The laboratory tests for the presence and precise concentration of hygroscopic salts, including nitrates and chlorides.

Diagnostic Value: Soluble ground salts are drawn up through masonry during rising damp and remain in plaster permanently. Salt analysis scientifically differentiates true rising damp from condensation or historic leak contamination.

Note: Plaster sampling requires minor material removal and is our only add-on involving minor invasive work.

Add-On 2

Mould Laboratory Testing & qPCR DNA Analysis

Price £299 + VAT

Surface swab or lift samples are submitted to an accredited laboratory for advanced qPCR DNA analysis.

Diagnostic Value: Accurately identifies exact mould species, measures contamination concentrations and detects hidden fungal growth inside cupboards or behind dry lining. Delivers impartial scientific evidence to guide safe environmental remediation.

Testing may be helpful when:

  • Musty odours persist
  • Mould continually returns after cleaning
  • Previous flooding or leaks have occurred
  • Contamination is suspected behind furniture or within cupboards
  • Growth may be concealed in restricted locations
  • Additional evidence is required before remedial work
  • Occupants have concerns about the internal environment

Results can help establish whether contamination appears limited or more significant and whether it may be connected to an underlying moisture problem. Testing applies to the locations sampled and should be interpreted alongside the property inspection.

Add-On 3

Gas, Chemical Vapour & Airborne Particle Testing

Price £299 + VAT

Comprehensive environmental air quality and gas screening tailored to specific property concerns.

Screening Suite Includes:

  • Indoor air quality indicators — IAQ
  • Volatile organic compounds —
  • TVOC/VOC
  • Formaldehyde — HCHO
  • Fine particles — PM1.0, PM2.5 and PM10
  • Dust and smoke particles
  • Sewer gas indicators — H2S, NH3 and CH4
  • Combustible gas screening — CH4 and C3H8
  • Carbon monoxide — CO
  • Hydrogen sulphide — H2S
  • Ammonia — NH3
  • Oxygen concentration — O2
  • Ventilation and stale-air assessment
  • Drain-odour investigation
  • Chemical-smell investigation
  • Post-leak air and surface-condition screening
  • Combustion gas indicators
  • Off-gassing from building materials
  • General airborne pollutant screening

Diagnostic Value: Identifies hidden airborne pollutants, drain odours, chemical off-gassing and stale air problems.

Note: This service is intended as preliminary screening. It does not replace emergency gas-leak procedures, professional gas appliance testing, specialist occupational-hygiene assessments or comprehensive laboratory air sampling.

Contact Us

For an in-depth survey of your property or simply to talk to one of our damp proofing specialists in London

Book and Pay for a survey

If you are ready to book a survey and pay, please complete this form:

Book Survey