Written guarantee · All London · Insurance-ready reports

No Find, No Fee Leak Detection London

Genuine no-fee outcome if we cannot pinpoint the leak — the guarantee is signed off in writing on the survey quote before we travel. No hidden call-out charge, no minimum fee, no small print discovered at invoice stage.

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What no find, no fee actually means — and why the phrase gets abused

“No find, no fee” is the most misused phrase in the London leak detection market. Every website advertises it. Very few outfits mean it in the sense a customer reads it. The common gap is a “minimum call-out fee” buried in the terms — £75, £120, £150 — payable whether the leak is located or not. Under those terms, the guarantee only means “you pay a smaller fixed fee if we fail” rather than the zero-fee outcome the phrase implies.

Our version is different, and the difference is written into the quote before the engineer travels. If our engineer deploys the full method suite — acoustic listening, thermal imaging, tracer gas where applicable to the symptom, moisture mapping, plus CCTV on waste pipes if the drainage is a suspect — and cannot pinpoint the leak within the workable margin defined in the quote, the survey fee is zero. Not reduced, not partial, not offset — zero. No travel charge, no call-out, no diagnostic time invoice. The four narrow exclusions (customer withdraws consent mid-visit, customer refuses one of the methods, access to an area we don't have permission to enter, or repeat survey to verify a completed repair) are all listed in the quote in plain English.

The pragmatic reason we can offer this without going bankrupt is a simple statistic. Across our 2026 leak survey work — over 480 residential surveys across every London borough — we have located the leak on the first visit in 96% of cases. Modern method-suite equipment (a calibrated FLIR thermal camera, an Aquaphon acoustic listening system, a Sewerin tracer-gas kit, a Protimeter capacitance moisture meter and a push-rod CCTV camera) applied by a properly trained engineer resolves nearly every real leak. The remaining 4% are almost entirely intermittent leaks that had temporarily stopped during the survey window, or leaks in areas we could not enter without landlord authorisation. Both categories are honourable no-fee outcomes and we book them as such.

The commercial economics work because a paying survey nine times out of ten funds the tenth as an occasional zero-revenue visit. What we do not do is compensate for the tenth by charging a hidden minimum on every quote. That is exactly the thing we advertise against — and the reason the guarantee has to be written on the paper before the engineer leaves base.

The four guarantee terms — in plain English

Every survey quote we issue includes the four points below in writing. Read them, question them, and cross-check them against any other quote you have received.

What no find, no fee means in practice

You pay zero for the detection survey if our engineer deploys the full method suite (acoustic listening, thermal imaging, tracer gas where applicable, moisture mapping, plus CCTV on waste pipes if the symptom points there) and cannot pinpoint the leak location within a workable margin. No hidden call-out charge, no "diagnostic time" fee, no travel invoice. The commitment is signed off in writing on the survey quote before the engineer travels.

The workable margin is defined explicitly in the quote — for a pressurised mains or heating leak, that is typically pinpoint within a 300mm square. For an underground supply pipe survey, within a 500mm square. Anything wider counts as an unsuccessful survey — you pay nothing.

When the guarantee applies

Standard residential leak surveys where the symptom is consistent with a locatable leak: boiler pressure dropping, damp patch on a ceiling below a bathroom, unexplained water meter movement, Thames Water leak notice, damp patch on a wall below a shower. The property must be accessible to our engineer during the survey visit, and any freeholder or managing-agent access permission must be in place before we arrive.

On over 96% of surveys carried out in 2026 we located the leak on the first visit. The 4% remainder split roughly evenly between (a) intermittent leaks that had temporarily stopped during the survey window (customer usually reported it returning weeks later), and (b) leaks in inaccessible areas we could not reach without landlord authorisation.

When the guarantee does not apply

Four exclusions apply to the no-fee outcome: (1) the customer requires access to areas the engineer cannot enter — locked risers in blocks of flats, freeholder-only voids, adjacent-property access we don't hold permission for; (2) the survey is aborted early because someone in the household withdraws consent mid-visit; (3) the customer refuses to allow one of the method-suite techniques (e.g. no injection of tracer gas because of a pet allergy) and the remaining methods cannot conclude; (4) work commissioned as a repeat survey to verify a completed repair — the engineer is not looking for a new leak in that context.

Every exclusion is explained in writing on the quote before the engineer travels. There are no surprise clauses discovered on the invoice.

Why competitors often can't honour the same guarantee

Many London leak detection outfits advertise "no find, no fee" but structure their pricing around a fixed minimum call-out that is due whether the leak is found or not. Others carry only one detection method (acoustic-only) and cannot honour a genuine full-method-suite guarantee — they simply can't deploy thermal or tracer gas, so an unsuccessful acoustic survey leaves the customer paying full price for a partial service.

Read every leak-detection quote for the exact wording. If the phrase "call-out fee applies" or "minimum survey fee" appears anywhere in the terms, the guarantee is not genuine. Ours is. It is signed off on the written quote before we travel — no small print, no hidden minimums, no travel invoice.

The insurance-claim workflow — how our survey unlocks trace and access

Every mainstream UK household insurer includes a trace-and-access benefit in the standard escape-of-water cover — typically £5,000, ring-fenced for locating and accessing the source of a leak. That benefit exists specifically to fund the kind of professional survey we run. Here is how it works in practice, from suspected leak to paperwork.

You have a suspected leak

Boiler pressure dropping, damp patch appearing, mystery water bill spike. You want a written diagnostic before you open a claim.

You call AK for the leak survey

We quote the survey with the written no-find-no-fee guarantee. Payment method is card on the day only after the leak is located.

Survey completed and written report issued

Report includes: moisture-mapping annotated floor plan, thermal images (JPEG plus CSV data), method log, precise leak location marked on plan, recommended remedial work, cost estimate. Formatted to standards Aviva, Direct Line, LV, Zurich, Allianz and RSA expect.

You open a claim with your insurer

Attach the written survey report. Most insurers now accept trace and access as an implicit part of the escape-of-water claim under the standard household policy — typically £5,000 benefit ring-fenced for tracing and accessing the leak source, plus separate cover for the water damage itself.

Insurer authorises trace and access

The loss adjuster reviews the report and authorises the trace-and-access spend — often including a retrospective refund of the survey fee you paid AK, plus authorisation for the follow-up repair.

Repair completed, drying, reinstatement

AK completes the leak repair (often same visit as the survey once the leak is located). Insurer separately funds drying, reinstatement (ceiling, flooring, decoration) via an approved damage-management contractor. You are back to normal in weeks not months, with paperwork.

Trace and access — the major UK insurers, at a glance

Every survey report we issue is formatted to the specification the loss adjuster at the major UK insurers expects. Here is how each mainstream insurer typically handles trace and access.

Aviva

Standard trace and access £5,000. Report must include moisture readings, method log, and pipe-material identification. Accepts our reports as-issued.

Direct Line

Standard trace and access £5,000 (higher on the "Plus" and "Home Plus" products). Requires location marked on floor plan and photographic evidence of moisture patches. All included in our report format.

LV=

Trace and access £5,000 (£10,000 on the "Home Plus" product). Loss adjuster typically pre-approves our engineer's recommended repair scope from the written survey report.

Zurich

Trace and access £5,000 standard, £10,000 for high-value homes. Prefers the loss adjuster to interview our engineer once the survey is complete — we make the engineer available by phone or on-site as required.

Allianz

Trace and access £5,000 (product-dependent). Requires a WRC-compliant CCTV report on any drainage-related leak — included as standard on our surveys where drainage is a suspect.

RSA / More Than

Trace and access £5,000 standard on More Than. Prefers itemised cost breakdown on the survey invoice separating detection from repair — our invoicing structure supports this by default.

Real London leak surveys — including a rare no-fee outcome

Three recent surveys, anonymised. The last is a genuine example of the guarantee working — the leak was intermittent, no fee was charged, and the follow-up survey when the leak returned was also under the guarantee.

Successful find — Camden mansion block ceiling drip

Damp patch spreading across kitchen ceiling for six weeks. Acoustic ruled out pressurised leak. Thermal showed nothing on hot pipes. CCTV of the flat above's bath waste picked up a hairline crack in a rubber olive seal — dripping only when the bath was drained. Repair £180, no ceiling opened. Guarantee not triggered — we located the leak.

Successful find — Wandsworth Victorian terrace, underground supply

Thames Water leak notice — 800 L/day unaccounted. Isolation confirmed leak between boundary and internal stop. Tracer gas located the split MDPE feed at 45cm depth, 1.8m from front door. Repair via keyhole excavation, one afternoon. Guarantee not triggered — leak pinpointed within 300mm.

Rare no-fee outcome — Islington flat with intermittent leak

Reported damp on a ceiling below a bathroom that had "stopped for now." Full survey deployed acoustic, thermal, moisture mapping, and CCTV of the wastes — no active leak signature at time of survey. Written report explained the intermittent nature. Zero charge to customer. Six weeks later customer reported the leak returned during a hot bath — repeat survey (booked at no charge under the guarantee) located a failing tile grout allowing overflow at high water levels.

No find, no fee across every London borough

The guarantee applies across all 32 London boroughs plus the M25 fringe. Click a borough for a page tailored to local plumbing conditions and leak patterns.

Frequently asked questions about the no find, no fee guarantee

Is your no find, no fee guarantee genuine or is there a hidden call-out charge?

Genuine — zero charge if we cannot locate the leak within the workable margin defined in the quote. The exact terms, including the workable margin (typically pinpoint within a 300mm square) and the four narrow exclusions (access refused mid-visit, method refused by customer, work commissioned as a verification survey, or areas we cannot enter for access-permission reasons), are all listed in writing on the survey quote before the engineer travels. No hidden call-out charge, no diagnostic time fee, no travel invoice.

What percentage of leaks do you actually find?

Over 96% of leak surveys carried out in 2026 located the leak on the first visit. The 4% remainder split roughly evenly between intermittent leaks that had temporarily stopped during the survey (customer typically reported the leak returning weeks later) and leaks in areas we could not access without freeholder authorisation. Every unsuccessful first survey qualified for the no-fee outcome, and where the leak later returned we booked a follow-up survey at no charge under the guarantee.

Do I still pay for the repair if you find the leak?

Yes — detection and repair are separate contracts, priced separately. The no-fee guarantee covers only the survey portion. Once the leak is located we provide a fixed-price repair quote, which you can accept, decline, or take to a different plumber. You are never obligated to use us for the follow-up repair.

Will my insurer refund the survey cost under trace and access?

Most standard UK household policies include trace and access as a component of the escape-of-water benefit — typically £5,000 ring-fenced for tracing and accessing the leak. If the leak damage triggers an escape-of-water claim, insurers commonly refund the survey fee retrospectively as part of the trace-and-access allowance. Our written report is formatted to satisfy the documentation requirements at Aviva, Direct Line, LV, Zurich, Allianz, and RSA.

What if my property is a listed building or in a Conservation Area?

The survey methods we use are all non-destructive — no drilling, no lifting floors, no opening walls unless the leak is located and the customer authorises access for repair. Listed-building status therefore does not affect the survey itself. Where an authorised access-for-repair opening would need Conservation Area or Listed Building consent, we advise on the process and coordinate with the local authority planning team as needed.

Can you survey a shared drain or a communal system?

Yes — with the freeholder or managing agent's written access permission in advance. Shared drainage and communal hot water systems in Victorian conversion flats and mansion blocks are common survey subjects. The report we produce specifies which section of the shared system contains the leak, which supports the freeholder's later recharge to the responsible leaseholder.

How long does the survey take?

Standard residential leak surveys complete in 45–90 minutes on site. Underground supply pipe surveys using tracer gas run 90–120 minutes because of the system isolation, gas injection, and surface scan sequence. The written report is emailed within 24 hours of the survey visit.

What does the survey cost if you do find the leak?

Standard residential leak survey £250–£350. Complex or multi-storey survey £350–£450. Underground supply pipe survey (tracer gas) £400–£550. CCTV drain survey £200–£350. Every quote is confirmed in writing before the engineer travels.

Do you carry public liability insurance?

Yes — £5,000,000 public liability via SiriusPoint International Insurance Corporation (UK Branch) acting through Eaton Gate MGU Ltd, policy number BE26ACTT000000018221, current period 07/05/2026 to 06/05/2027. The certificate is provided with every survey quote — managing agents and freeholders routinely require this before granting access.

Do you work with landlords and property managers?

Yes — managed portfolios get monthly consolidated invoicing, priority dispatch on out-of-hours calls, and a dedicated account manager. Every survey produces a WRC-compliant written report delivered to the property file within 24 hours. For portfolios above 20 properties we can put together a pre-agreed detection call-out rate and out-of-hours protocol.

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The guarantee is signed off in writing on the survey quote — before the engineer travels.

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