07576 573615tom@cbsdamp.co.uk Mon–Fri 8am–8pm · Sat 8am–1pm · Sun closed About Services Areas Our work Contact 07576 573615Request Free Survey HomeServicesDamp surveys & diagnosis Damp proofing & remedial treatment specialists # Free Damp Surveys& Diagnosis in Harrow Find out exactly what is causing the damp, what it takes to fix it, and what it costs, in writing, at a fixed price, with no charge for the visit and no obligation to proceed. Request your free survey 07576 573615 Survey, diagnosis and written quotation at no cost · Approved contractor for Sovereign and Wykamol £0 Survey, diagnosis and written quotation Fixed price Quotations, never a day rate 10 years Guarantees available on the treatment we specify £2m Public liability insurance held Service overview ## A survey that tells you the cause, not just that the wall is wet A damp survey is a diagnostic exercise. Anyone can put a meter on a wall and confirm a reading; the value is in establishing which mechanism is producing it, because rising damp, penetrating damp, condensation, plumbing leaks and construction moisture all look broadly similar on a decorated surface and every one of them has a different remedy. Our survey covers the affected rooms and the external envelope around and above them. We record moisture patterns and heights, check external ground levels, pointing, render, sills, rainwater goods and visible roof details, look for bridging of an existing damp proof course, and take account of heating and ventilation where condensation is a candidate. You then receive a written fixed-price quotation for the works needed. It sets out the scope, so you can see what is being treated and why, and compare it properly against anyone else's proposal. The survey is for homeowners who have noticed staining, landlords with a tenant complaint, buyers and sellers dealing with a valuation or homebuyer report that flags damp, and anyone whose previous damp treatment has failed and wants to know what was missed. ### Who it is for Homeowners, landlords, buyers, sellers and agents who need the cause of damp established before spending money on treatment. ### When it is needed When staining appears or returns, when a surveyor's report asks for specialist damp investigation, or before committing to a purchase. ### Why it needs a specialist Specification decisions follow the diagnosis. A wrong diagnosis means the wrong system, no lasting result, and a second bill. What happens if it is left ## What guessing the cause actually costs Every failed damp job we are called to started with a diagnosis that was never really made. A damp proof course injected into a wall suffering penetrating damp. A wall replastered while a gutter was still leaking onto it. Anti-mould paint sold as a cure for a condensation problem driven by ventilation. The other cost is delay. Damp that is misdiagnosed continues, and while it continues it damages plaster, joinery, embedded timbers and masonry. The repair that would have been straightforward becomes carpentry and brickwork. ### Paying twice Treatment aimed at the wrong mechanism does not work. The money spent on it is gone, and the correct work still has to be done. ### Damage escalates Months of continued wetting move the job from decoration to timber decay, spalled brickwork and failed plaster. ### Sales stall A valuation that flags damp without a specialist report behind it invites retentions, renegotiation or a buyer walking away. ### Tenancy risk Landlords who treat symptoms rather than causes end up with recurring complaints and a documented history of ineffective action. ### Over-specification Some contractors quote the largest possible scope because it is safer for them. A diagnosis lets you buy only the work needed. ### The common mistake Accepting a quote from a visit that never looked outside. The cause of internal damp is very often on the external elevation. Our process ## A fixed sequence, so nothing is guessed at 01 ### Booking Call or send the enquiry form with a description of what you are seeing and the postcode. We arrange a time that suits, including evenings up to 8pm on weekdays. 02 ### Internal inspection Affected rooms assessed: moisture pattern and height, plaster condition, salting, joinery, ventilation and heating, and any previous treatment. 03 ### External inspection Ground levels, DPC line, pointing, render, sills, copings, rainwater goods and visible roof details checked for the routes water uses. 04 ### Diagnosis explained We tell you what is causing it in plain language, what is urgent, and what can wait, while we are still on site. 05 ### Written fixed-price quotation A defined scope with a fixed price follows, with guarantee details for the treatment proposed. No charge, no obligation. What you get ## The result you are paying for ### You buy only what you need A specific diagnosis produces a specific scope, which is the cheapest route to a dry wall. ### No cost to find out The survey, diagnosis and written quotation are free, so getting a straight answer costs you nothing but the appointment. ### Something to compare against A written scope lets you judge other quotes on what is actually included, not on the headline number. ### Evidence for a sale or lender A specialist assessment and quotation is what valuers and buyers ask for when a report mentions damp. ### Peace of mind either way If the problem is minor, or is condensation you can manage yourself, we say so rather than sell you a treatment. ### One contractor to completion If you proceed, the same business does the treatment, the plastering and the making good, under a fixed price. In detail ## How damp is diagnosed: patterns, methods and evidence Diagnosis rests on pattern recognition backed by measurement. Each mechanism leaves its own signature, and the signatures are distinct once you know what to look at. ### Reading the pattern Rising damp holds a fairly consistent height above floor level, usually with a tide mark, salt deposits and blown plaster, and it does not respond much to the weather. Penetrating damp appears as isolated patches at any height and darkens during and after driven rain. Condensation collects on cold surfaces, window reveals, external corners, behind wardrobes on north walls, often with black spot mould and no salting. Plumbing and drainage leaks mimic all three but usually stay constant regardless of weather and can be localised to pipe runs, wet rooms or the floor above. Construction moisture in new render, screed or plaster reduces steadily over months rather than persisting. ### Measurement and inspection Electrical resistance moisture meters give useful comparative readings across a wall and up its height, and they are read as a pattern rather than a single number, because salts and foil-backed papers can skew them. Where a reading needs interpreting, it is checked against the physical evidence: plaster condition, efflorescence, timber state, and whether the affected zone corresponds to something outside. The external inspection carries as much weight as the internal one. Ground levels above DPC, render bridging the DPC, open or eroded joints, cracked or hollow render, perished mastic at openings, missing sill drips, loose copings, blocked or split rainwater goods and defective flashings are all recorded, because each one is a potential entry route with a matching internal pattern. ### Previous treatment and failed work Where damp has been treated before, we look for the three usual omissions: an injected damp proof course with no salt-retardant replastering, internal waterproof coatings applied over an untreated ingress, and bridging that was never corrected so a sound DPC is being bypassed. Knowing what was done previously changes the specification, and often reduces it, there is no point paying twice for an element that was done correctly the first time. ### Surveys for sales, purchases and lending When a mortgage valuation or homebuyer report refers a damp issue for specialist investigation, what is needed is a clear statement of cause and a costed scope of remedial work. That is what our survey produces, and where treatment goes ahead it is backed by a 10-year workmanship guarantee and a 10-year QANW insurance-backed guarantee, the documentation buyers, surveyors and lenders look for. For sellers, having the diagnosis and a fixed-price quotation in hand keeps control of the negotiation rather than leaving a buyer to imagine the worst-case figure. ### Residential and commercial Domestic surveys cover houses, flats, maisonettes and converted properties, including leasehold situations where responsibility for the defect may sit with the freeholder, worth establishing before anyone commissions works. Commercial surveys follow the same method with added attention to trading impact, access equipment and phasing. In both cases the outcome is the same: a cause, a scope and a fixed price. Carried out across Harrow, Chiswick, Isleworth, Chelsea, Pinner, Stanmore, Edgware, Ealing, London, Middlesex, Watford, Buckinghamshire, Slough, Brent, Surrey, High Wycombe, West London, see the full list of areas covered. Questions ## Damp surveys & diagnosis, common questions Is the damp survey really free?Yes. The site visit, the diagnosis and the written fixed-price quotation are provided at no cost and with no obligation to proceed. How long does a survey take?Most domestic surveys take under an hour for a single problem area, longer where several elevations or rooms are involved or where previous treatment needs unpicking. Will I get a written report?You get the diagnosis explained on site and a written fixed-price quotation setting out the scope of works. If you need a formal report for a lender or solicitor, tell us when you book so we know what the document has to support. Can you survey a property I am buying?Yes, subject to access being arranged with the seller or agent. Buyers commonly commission a survey after a valuation or homebuyer report flags damp. What if it turns out to be condensation?We tell you, explain what is driving it, and advise on what would actually help. We do not sell damp proofing for a condensation problem. How soon can you attend?We take calls Monday to Friday 8am to 8pm and Saturday 8am to 1pm, and prioritise surveys where a sale, remortgage or tenancy is waiting. Tell us your deadline when you call. Do you charge for the quotation?No. Quotations are free, fixed-price and set out the works included. There are no day rates. Will you tell me if nothing needs doing?Yes. Some visits end with advice and no quotation, and that is a legitimate outcome of a diagnostic survey. What areas do you survey?London, Middlesex, Watford, Buckinghamshire, Slough, Brent, Surrey, High Wycombe and West London. A previous damp treatment failed. Will you survey it?Yes. Failed treatments are one of the most common reasons we are called, and the survey identifies what was misdiagnosed or omitted. Free survey ## Book a free damp survey and get a straight answer Describe what you are seeing and where, and we will arrange a visit, identify the cause and give you a written fixed price for putting it right. No charge for the visit, no obligation afterwards. - Free survey, diagnosis and written fixed-price quotation - 10-year company workmanship guarantee on damp treatment - 10-year QANW insurance-backed guarantee - Sovereign & Wykamol approved contractor - £2,000,000 public liability insurance Call 07576 573615 Related services ## Work that often goes with it ### Rising damp treatment A failed damp proof course is diagnosed, treated with an accredited Sovereign or Wykamol system and replastered to a decoration-ready finish, priced as a fixed sum before any work starts, and guaranteed for ten years. Rising damp treatment in London & Middlesex ### Penetrating damp treatment Damp that worsens after rain is coming in from somewhere. We find the route: pointing, render, sills, gutters or roof detail; correct it, then repair the wall inside. Free survey, fixed price, no guesswork. Penetrating damp treatment in London & Middlesex ### Structural waterproofing & tanking Below-ground rooms need a waterproofing system, not a coat of damp-seal paint. Membrane and cementitious tanking specified to suit the structure, installed as an approved Sovereign and Wykamol contractor, with a free survey and a fixed price. Structural waterproofing & tanking in London & Middlesex ### Damp surveys & diagnosis in the areas we cover Damp surveys & diagnosis in HarrowDamp surveys & diagnosis in PinnerDamp surveys & diagnosis in StanmoreDamp surveys & diagnosis in EdgwareDamp surveys & diagnosis in EalingDamp surveys & diagnosis in ChiswickDamp surveys & diagnosis in IsleworthDamp surveys & diagnosis in ChelseaDamp surveys & diagnosis in MiddlesexDamp surveys & diagnosis in BrentDamp surveys & diagnosis in LondonDamp surveys & diagnosis in West LondonDamp surveys & diagnosis in WatfordDamp surveys & diagnosis in SloughDamp surveys & diagnosis in BuckinghamshireDamp surveys & diagnosis in High WycombeDamp surveys & diagnosis in Surrey All damp proofing & building servicesRising damp treatmentPenetrating damp treatmentStructural waterproofing & tankingPlasteringRenderingBrickworks & repointingDamp proofing project photographsBook a free damp survey Damp proofing, structural waterproofing and remedial building works across London and the surrounding counties. Tom Charge, Owner. ### Contact - 07576 573615 - tom@cbsdamp.co.uk - C/O MG Tax, 166 College Road, Harrow, England HA1 1BH ### Hours - Monday8am – 8pm - Tuesday8am – 8pm - Wednesday8am – 8pm - Thursday8am – 8pm - Friday8am – 8pm - Saturday8am – 1pm - SundayClosed ### Guarantees - 10-year company workmanship guarantee - 10-year QANW insurance-backed guarantee - 6-month guarantee on building work - Sovereign & Wykamol approved contractor - £2,000,000 public liability insuranceAboutServicesAreasOur workContact ### Damp proofing & building services - Rising damp treatment - Penetrating damp treatment - Damp surveys & diagnosis - Structural waterproofing & tanking - Plastering - Rendering - Brickworks & repointing - Brick stitching - General building - Small refurbishment & remedial works ### Areas we cover - Harrow - Pinner - Stanmore - Edgware - Ealing - Chiswick - Isleworth - Chelsea - Middlesex - Brent - London - West London - Watford - Slough - Buckinghamshire - High Wycombe - Surrey © 2026 Charge Building Services Ltd. 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