Basement Tanking
London Damp Specialists is a waterproofing firm that provides professional damp proofing, cellar and basement draining services in London.
Homes in the London area, in particular, have many types of cellars and basements depending upon their location and use.
Daylight basement
Is located on a slope, where part of the floor is above ground with a door to the outside. Part of the floor lower than the ground level is the true basement space and is attached with ventilated windows to prevent damp problems.
Look-out basement
Is constructed even on a flat area where the basement walls extend above the ground level with the windows above grade.
Walk-up basement
Is one that has an exterior entrance through a stairwell with basement doors to stop rainwater from collecting and causing water damage.
A Fully underground cellar
Is a room below ground level in a house which is used for storing wine or household items. It has to remain at constant cooling with small forms of ventilation.
Underground crawl space
Is a type of basement where one cannot stand upright but crawl on the soil below. It is mainly used for storage and rat-proofing purposes.
Watch this video to find out more!
Water Proofing Company London
Here at London Damp Specialists Ltd we are experts in all areas of damp and how to avoid it. Get in touch with us today to discuss your requirements and let us visit your property or business to analyse the problem and come up with a suitable remedy. Call our experienced team today on 020 7458 4864.
Which Basement or Cellar Tanking System?
All cellar tanking and basement waterproofing systems are created by removing of all damaged plasterwork and damaged masonry, stripping your basement back to its original building material. Then the foundation layer is cleaned and prepared for the tanking process.
London Damp Specialists offers a choice of two cellar / basement waterproofing systems:
- Cavity drainage sump and pump system
- Tanking and rendering system
Cavity Drainage Sump And Pump
If your cellar is not going to remain dry through the use of a waterproof barrier (tanking and rendering system), then cavity drainage systems are the most robust solution as they allow water to penetrate in a strictly managed and controlled way.
Textured membrane is fitted to the basement’s walls, floor and ceiling then the entire construction is covered with specialist plasterboard, insulation and screed. A hidden pump is installed to manage and direct water out of the system into the normal water table or wastewater source.
Cavity drainage systems will leave you with a completely dry inner room which you can finish and decorate exactly as you please from kitchens, bathrooms, studies, bedrooms, lounges and snugs. This amazing system means the cavity drainage approach gives you excellent results and is simple to maintain and repair.
No matter the condition of your basement here at London Damp Specialists we of waterproof basements in in manner of homes.
Basement Tanking London and rendering system
Cementitious tanking slurry is an easy to use, highly effective tanking method. As a cement-based powder which, when applied to the walls, ceiling and floor will then bond with the underlying surface to give a waterproof barrier. We then finished off the tanking with a specialist plaster to complete waterproofing.
A cemented multi-coat render system has a high performance in resisting the water seepage through the decayed wall or mortar joints. It is designed for applying directly to the brickwork that is uneven and has high level of moisture. The render also has an adhesive coat that sticks to the cracks resulting in good texture. Cemented multi-coat render applied on the external wall acts as weather resistant repelling damp infestations and growth of moulds and suitable for most types of brickwork or block work.
Customer Testimonials
As time is of the essence, we would like to get to work as soon as possible; of course, we are happy to fit in with the customer’s schedule. If you are unable to leave work, we are happy to do the work with no one at home; all our employees are CRB/DBS checked.
While some insurance providers might offer that, it would be best to check with your carrier. They will be able to provide you with a more accurate answer on this matter.
At London Damp Specialists, we have a working relationship with the top insurer GPI and you can take out a policy that covers damage caused by damp.
We do not require payment until the work is dry and you are satisfied with the service.
Yes, at London Damp Specialists, we treat all forms of timber rot including woodworm.
We offer a range of survey services; check our homebuyer survey page for a list of services and prices. We are competitively priced and we will match any quote from a reputable company.
Our 5 Step Process
01
Initial Consultation
Tell us about your damp issue and we’ll guide you on next steps. It's an opportunity for you to ask questions and gather information.
02
Site Visit
Next, we visit your property to find the root cause of the issue. We’ll also assess the local environment, and take measurements or observations.
03
No Obligation Quote
Then we’ll send a detailed estimate of the costs involved, with no hidden extras, and provided to you without any commitment. You can review the financial aspect before making any decisions.
04
Work Carried Out
Our expert team carries out the work as planned, to the agreed timeline and quality standards, with minimum disruption to you.
05
Payment
The last step is payment, once the work’s complete, your home is dry and you’re satisfied with the results.
30-Year Warranty + 10-Year Insurance-Backed Guarantee
Your damp repair is protected for decades.
- 30-Year Warranty: All remediation work is covered by a 30-year workmanship warranty, protecting your property against recurrence of the treated issue.
- 10-Year Insurance-Backed Guarantee (IBG): Your guarantee is insurance-backed for 10 years through Quality Assured National Warranties (QANW), so your cover remains valid even if we’re unable to fulfil it ourselves.
- 24-Hour Report Delivery: Comprehensive digital survey reports are typically issued within 24 hours of the inspection’s completion.
Qualification list
PCA-Certificated Surveying
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CSDB (Certificated Surveyor of Dampness in Buildings): This certification ensures your damp diagnosis is carried out to a recognised industry standard.
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CSTDB (Certificated Surveyor of Timber and Dampness in Buildings): This means we can assess timber decay, wet rot, dry rot and wood-boring insect activity in the same visit, giving you a complete picture of your property’s condition
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CSSW (Certificated Surveyor in Structural Waterproofing): Where basement or below-ground waterproofing is involved, this certification ensures that any tanking or structural waterproofing solution we recommend is specified the first time correctly.
CSCS
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CSCS (Construction Skills Certification Scheme): Our experts carry a CSCS card, which confirms they’re authorised and trained to work safely on-site, giving you confidence that the team in your home meets recognised industry safety standards.
Asbestos awareness
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Asbestos awareness: Older properties may contain asbestos, particularly in areas where damp and timber work are common. Our team holds UKATA-accredited Asbestos Awareness training as standard and where a job risks disturbing such materials, our experts are more than qualified to manage the work safely and in full compliance with UK regulations.
Equipment Used During Our Surveys
Equipment Used During Our Surveys
Purpose:
Takes comparative moisture readings from walls, ceilings, floors and timber to identify abnormal moisture patterns.
Common Uses / Notes:
Used when investigating rising damp, penetrating damp, condensation and leaks. Readings support the survey but are not a diagnosis on their own.
Subsurface Moisture Meter
Purpose:
Detects moisture beneath the surface of suitable building materials.
Common Uses / Notes:
Helps determine whether moisture is confined to surface finishes or extends into the building fabric.
Non-Damaging Moisture Scanner
Purpose:
Scans surfaces for hidden moisture without causing damage.
Common Uses / Notes:
Ideal for decorated walls, ceilings and flooring where pin testing would be undesirable.
High-Resolution Borescope Camera
Purpose:
Inspects hidden or difficult-to-access areas without opening up large sections of the building.
Common Uses / Notes:
Used beneath floors, inside cavities, behind walls and around pipework to identify damp, leaks, decay and concealed defects.
4K Aerial Inspection Drone
Purpose:
Captures high-resolution images of roofs and other inaccessible external areas.
Common Uses / Notes:
Inspects roof coverings, chimneys, flashing, gutters, valleys, parapets and high-level masonry. Subject to weather, safety requirements and flight regulations.
Atmospheric Humidity Sensor
Purpose:
Measures indoor relative humidity levels.
Common Uses / Notes:
Helps assess condensation and mould risk alongside temperature, ventilation, heating patterns and room usage.
Gas Detection Monitor
Purpose:
Screens for certain airborne gases where unusual odours are present.
Common Uses / Notes:
May detect gases associated with drainage, combustion or flammable substances. Does not replace inspection by a Gas Safe registered engineer where gas appliances or pipework are involved.
Thermal Imaging System
Purpose:
Identifies temperature differences across building surfaces.
Common Uses / Notes:
Helps locate cold spots, thermal bridging, insulation defects and areas associated with concealed moisture. Results always require further investigation to confirm the cause.
Basic Socket and RCD Tester
Purpose:
Performs limited electrical checks during comprehensive surveys.
Common Uses / Notes:
Can identify basic socket wiring issues, AC voltage and RCD operation. It is not an Electrical Installation Condition Report (EICR).
Chemical Vapour Testing Device
Purpose:
Screens for airborne volatile organic compounds (VOCs) and formaldehyde.
Common Uses / Notes:
Used where chemical odours, emissions from materials or indoor air-quality concerns are suspected after leaks or refurbishment.
Fine Air Particle Counter
Purpose:
Measures airborne particulate matter (PM1.0, PM2.5 and PM10)
Common Uses / Notes:
Assists with investigations involving dust, smoke, mould concerns, post-construction contamination and indoor air quality following water damage.
Extraction and Air-Movement Tester
Purpose:
Measures the performance of extractor fans and mechanical ventilation systems.
Common Uses / Notes:
Used in kitchens, bathrooms and utility rooms to identify poor ventilation that may contribute to condensation and mould growth.
Survey Levels and Equipment Provided
Basic Moisture Survey
Standard price: £299 + VAT
Special offer: £199 + VAT until the end of this month
The Level 1 survey provides a basic assessment of the main accessible internal surfaces. It is most appropriate for simple, localised damp concerns where advanced testing is not required.
Equipment Included
- Professional damp meter
Survey Checks
- Accessible walls
- Accessible floors
- Ceilings
- Visible plumbing and drainage leak inspection
- Damp-control and prevention information
Suitable For
This survey is suitable for a customer who has found an isolated damp patch, suspects rising damp in a limited area or wants a straightforward check of the property’s accessible surfaces.
Only a standard damp meter is included. Customers requiring deep moisture detection, timber inspection, thermal imaging or roof inspection should select a higher survey level.
The survey fee will be deducted if we carry out the recommended work.
Damp, Moisture and Timber Survey
Standard price: £399 + VAT
Special offer: £299 + VAT until the end of this month
Level 2 includes everything in the Level 1 inspection and adds deeper moisture detection, non-invasive scanning and timber assessment.
Equipment Included
- Professional damp meter
- Deep-reading moisture meter
- Non-invasive moisture scanner
Survey Checks
- Accessible walls, floors and ceilings
- Visible plumbing and drainage leak checks
- Subsurface moisture readings
- Non-invasive scanning of appropriate materials
- Accessible underfloor and subfloor checks
- Wet rot inspection
- Dry rot inspection
- Woodworm inspection
- Damp prevention information
Suitable For
This level is intended for customers who require a more detailed inspection of dampness and timber condition. It is appropriate when moisture may be concealed within building materials or beneath accessible flooring.
The survey may identify evidence of timber decay or wood-boring insects and assess moisture in locations that cannot be properly examined with a surface meter alone.
Level 2 is particularly useful for homebuyers and sellers who want more information about damp and timber before completing a transaction.
The amount paid for the survey will be deducted from repairs undertaken by us.
Full Damp and Property Condition Survey
Standard price: £499 + VAT
Special offer: £399 + VAT until the end of this month
Level 3 is our most detailed inspection. It combines the checks from Levels 1 and 2 with advanced diagnostic technology, ventilation measurements and external roof-level assessment.
Equipment Included
- Professional damp meter
- Deep-reading moisture meter
- Non-invasive moisture scanner
- Thermal imaging camera
- Indoor humidity sensor
- HD borescope camera
- Airflow and ventilation tester
- 4K inspection drone
- Socket and RCD testing device
Survey Checks
- Accessible walls, floors and ceilings
- Visible plumbing and drainage
- Deep moisture investigation
- Non-destructive moisture scanning
- Accessible floor voids and subfloors
- Wet rot, dry rot and woodworm
- Infrared thermal imaging
- Indoor relative humidity
- Extractor-fan performance
- Borescope examination where suitable
- Visible damp-proof course
- External brickwork and pointing
- Roof coverings and junctions
- Chimney stacks and flashing
- Guttering and rainwater systems
- High-level exterior areas
- General visible structural condition
- Basic Electrical Test, socket and RCD screening
- Drone photographs, subject to safe flying conditions
Suitable For
The Level 3 survey is recommended for buyers, sellers and existing owners who want the most extensive moisture assessment available.
It is especially useful for older properties, houses with several reported defects, basement buildings and cases involving damp, mould, leaks, poor ventilation, timber decay or roof problems.
The inspection considers the property as a connected building rather than examining only the visible damp patch. A roof or gutter defect, for example, may allow water to enter at a high level and appear some distance away internally.
The drone component provides valuable information about roofs, chimneys, parapets and guttering that cannot normally be seen from the ground. These areas may contain hidden repair costs capable of affecting a property purchase.
Identifying damage before buying can help the purchaser budget correctly, request further specialist advice or use the findings during negotiations. Even a relatively small roof defect may cost more to repair than the difference between the survey packages.
If we complete the recommended remedial work, your survey payment will be credited against the price.
Specialist Survey Add-On Services
For complex damp investigations, we offer three specialised laboratory and environmental testing add-ons:
Laboratory Analysis of Plaster Samples
Price £299 + VAT
Description: Small plaster samples are extracted from affected masonry walls and submitted to an independent testing laboratory. The lab analyses the sample for hygroscopic salts (specifically nitrates and chlorides).
Value: Scientifically differentiates true rising damp (which deposits ground salts over time) from surface condensation or lateral penetrating damp. Ensures that remedial recommendations are based on chemical analysis rather than surface meter readings alone.
This service can be beneficial when:
- The cause of low-level dampness is disputed.
- Moisture-meter readings are inconsistent.
- A property has undergone previous damp-proofing.
- Old plaster continues to attract moisture.
- Independent laboratory evidence is required.
- Several possible moisture sources are present.
Note: Salt analysis is only one part of the investigation. Results must be assessed alongside the location of moisture, condition of the masonry, external ground levels, damp-proof course and potential plumbing or rainwater defects. Requires minor invasive plaster sampling (the only add-on requiring material removal). Survey fee credited when repairs are completed by us.
Mould Identification & qPCR DNA Testing
Price £299 + VAT
Description: Surface swab samples are collected and sent to an accredited laboratory for advanced qPCR DNA analysis. Identifies exact mould species, measures spore concentrations and detects hidden fungal growth behind furniture, within void spaces, or under floorboards.
Value: Provides precise scientific data regarding mould toxicity and contamination levels, helping establish the exact scale of cleaning, drying and structural remediation needed.
Laboratory mould testing may be useful when:
- There is an unexplained musty odour.
- Visible mould repeatedly returns.
- Water damage occurred previously.
- Mould is suspected behind cupboards or furniture.
- Contamination may be present in a concealed location.
- The visible extent of growth is uncertain.
- Independent results are needed.
- Remediation work is being planned.
Note: The results can provide a clearer indication of whether contamination appears minor, concentrated or potentially widespread. This information may be used when deciding the scale of cleaning, removal, drying or remedial work required. Testing should be combined with an investigation of the moisture source. Removing visible mould without resolving the underlying condensation, leak or ventilation problem may allow it to return. Survey fee credited against subsequent remediation works completed by us.
Air Quality, Gas, Vapour & Airborne Particle Screening
Price £299 + VAT
Description: Comprehensive environmental air testing including:
- Indoor environmental quality – IAQ
- Volatile organic compounds – VOC and TVOC
- Formaldehyde – HCHO
- Fine airborne particles – PM1.0, PM2.5 and PM10
- Dust and smoke particles
- Sewer gases – H2S, NH3 and CH4
- Flammable gases – CH4 and C3H8
- Carbon monoxide – CO
- Hydrogen sulphide – H2S
- Ammonia – NH3
- Oxygen measurement – O2
- Ventilation and stale-air assessment
- Drain-smell investigation
- Chemical-odour investigation
- Air checks following a leak or flood
- Combustion-related screening
- Building-material off-gassing assessment
- General airborne pollutant monitoring
Value: Pinpoints invisible airborne hazards, toxic sewer gases, chemical off-gassing and foul odours resulting from damp or trapped water.
This service can assist when investigating:
- Persistent foul smells
- Suspected sewer or drain odours
- Chemical smells
- Stale indoor air
- Odours following water damage
- Possible stagnant water
- Building material emissions
- Fine dust after construction work
- Poorly ventilated rooms
Note: Unpleasant odours can have several possible sources. Measurements for specific gases, compounds and particles may help identify which source requires further investigation. The assessment is a screening service and does not replace specialist gas-safety, environmental or medical testing where this is necessary. Survey fee credited against subsequent repair works completed by us.



