Frequently Asked Questions

Non-invasive leak detection means locating the source of a hidden water leak without opening up walls, lifting floors, or excavating — before you know exactly where to look. We use thermal imaging cameras, tracer gas, and acoustic listening devices to find the precise point of pipe failure through floors, walls, and concrete. The result is that we can mark an exact spot for access rather than opening up a large area to search. In most investigations, we locate the leak without making a single access point.

If we cannot locate the source of the leak during an investigation, you pay nothing for the investigation itself. The guarantee covers the detection work. If access work has been agreed in advance and is carried out as planned but the leak is not found, you pay only for the agreed access — not the full investigation fee. We will always be transparent about the scope before starting. We offer this guarantee because our detection success rate is consistently high and because we believe the risk of uncertainty should sit with the specialist.

Most investigations take between one and three hours on-site, depending on the property size, the suspected leak type, and how many areas need to be checked. A straightforward mains supply pipe investigation in a two-bedroom flat typically takes 60 to 90 minutes. A more complex investigation — such as inter-floor leaks in a large house or pressure loss on an underfloor heating system with multiple zones — may take two to three hours. We will give you a time estimate when you book, and we will not rush the investigation to meet an arbitrary deadline.

Yes. The majority of our investigations take place in fully occupied residential properties. Our detection methods cause minimal disruption — no drilling, no lifting of large floor areas, and typically no access to more than one or two small points in the property. We explain the process to your tenants or household members before starting and keep them informed throughout. For investigations in occupied HMOs or flats, we agree a time that minimises disruption to all residents.

We cover all 32 London boroughs, the full Surrey county area, and North and West Kent — including Orpington, Sevenoaks, Dartford, and surrounding towns. For London boroughs, emergency response times are typically two to four hours. Surrey and Kent follow the same target. If you're unsure whether your specific location falls within our area, call us on 0203 886 2316 and we'll confirm straight away.

No. We do not charge a separate call-out fee. Our pricing is based on the type of investigation required and the detection method used, not on the fact of visiting your property. You will receive a fixed price before any work begins — no open-ended hourly billing, and no surprise additions at the end. The only caveat is agreed access work: if we locate the leak and access work is required to repair it, this is priced separately and agreed before we proceed.

Yes. We operate 24 hours a day, seven days a week, including weekends and bank holidays. There is no additional out-of-hours surcharge on the investigation fee. Emergency response times are typically two to four hours across London regardless of time of day. For non-emergency investigations, we offer appointments at times that suit you, including evenings and weekends.

Most standard home buildings insurance policies include trace and access cover as a standard clause. This covers the cost of locating a hidden water leak, not just repairing the damage it caused. Check your policy schedule for "trace and access," "escape of water," or "accidental damage" clauses. If you can't find it, call your insurer before booking — they can confirm cover in a few minutes. Even policies that don't explicitly name trace and access often include it under accidental damage cover.

"Trace" refers to locating the source of the leak — the specialist investigation work. "Access" refers to the physical work required to reach the pipe — lifting a tile, opening a small section of screed. Trace and access cover pays for both of these elements, separately from the cost of repairing the pipe itself. Some policies cover the repair cost too; others cover only the trace and access. Our written report covers both elements in sufficient detail to support a claim under either policy type.

Our reports are accepted by all major UK home insurance providers, including Aviva, AXA, Zurich, RSA, LV=, Direct Line, Hiscox, Legal & General, Allianz, and NFU Mutual. Our reports are formatted to meet standard insurer evidence requirements: investigation method, equipment used, findings, photographs, and identified leak source. If you have a less common insurer or a specialist policy, call us and we can confirm whether our format has been accepted previously.

Yes — contact your insurer before the investigation to open a claim and get a reference number. Some insurers ask you to use a specific approved specialist or panel company. Call us first and we can confirm whether we're on your insurer's panel. Where we are not on the panel, our report can still be submitted as independent specialist evidence alongside any panel company's attendance. Do not wait for insurer approval before acting on an active leak — document what you can and act to prevent further damage.

Yes. Our reports provide precise documentation of investigation method, findings, and evidence of the leak source and its cause. If a claim has been rejected due to insufficient evidence, a comprehensive detection report can be submitted as supporting evidence to request reassessment. We cannot advise on insurance law or negotiate on your behalf, but customers have successfully used our reports to challenge initial rejections from major providers.

Thermal imaging cameras detect differences in surface temperature. Water escaping from a pipe under pressure or gravity is a different temperature to the surrounding structure — typically cooler for cold water pipes and warmer for hot water, central heating, or underfloor heating pipes. The camera produces a colour image that shows temperature gradients, allowing our engineer to see the path and extent of water penetration through a floor or wall without touching the surface. Thermal imaging is fast, covers large areas, and is effective on most substrates.

Tracer gas detection involves introducing an inert gas mixture — typically 5% hydrogen and 95% nitrogen — into the pipe system under low pressure. The gas migrates through the surrounding material at the point of pipe failure and rises to the surface, where a sensitive probe detects it. Tracer gas is particularly effective for cold water mains leaks beneath concrete floors and screed, where thermal imaging alone may not provide sufficient contrast. It is the most accurate method for locating precise failure points on sub-floor supply pipes.

Acoustic detection uses sensitive ground microphones and listening equipment to pick up the sound of water escaping under pressure from a pipe. Water leaking through a small hole creates a characteristic frequency range that differs from background noise. Our equipment amplifies and analyses these sounds through concrete, tarmac, and other surfaces, allowing an engineer to correlate position with the highest intensity and identify the leak location. Acoustic detection is particularly effective on mains water pipes at higher pressures and on exposed surfaces.

Underfloor heating leaks typically present as gradual pressure loss on the system with no visible signs of water. We start with pressure testing to confirm the system is losing pressure and to identify which zone or circuit is affected. Thermal imaging is then used to map the floor temperature and identify where the circuit is running cold — indicating that water is escaping at that point. In some cases, tracer gas is introduced into the isolated circuit for precise pinpointing. We cover all underfloor heating types including water-fed systems in concrete, screed, and timber suspended floors.

Yes — in most cases. Tracer gas migrates through concrete at the failure point, and thermal imaging detects temperature changes at the surface. Both methods locate leaks through concrete without access. The only situation where surface access may be required before pinpointing is when the concrete is very thick (over 300mm), has a dense composite layer, or has a surface treatment that limits gas migration. In these cases we will explain the limitation before starting and confirm what's possible with the specific substrate.

Our investigation fees are fixed-price based on the type of investigation required — not hourly. The specific price depends on the detection method, property type, and complexity. We provide a clear quote before starting, and that price does not change unless you request additional scope. Call us on 0203 886 2316 or use the Get an Estimate page for a price indication specific to your situation. For investigations covered by trace and access insurance, the cost is typically reimbursed in full by your insurer.

Call us on 0203 886 2316 — 24 hours a day, seven days a week — or submit an enquiry through our contact page. For emergencies, calling is always faster. We'll ask a few questions about the symptoms and your property, confirm the investigation scope and price, and book a time. For same-day emergency callouts we don't require a booking form — call us and we'll dispatch an engineer.

Yes. We provide a fixed price before any work begins, based on a phone or online enquiry. The price does not change on the day unless you add scope. We don't conduct a site survey before quoting — the type of investigation and the associated price are determined by the symptoms you describe and the property type. In unusual cases where the leak type is ambiguous, we may confirm the exact approach and price on arrival after a brief assessment, but this will always be communicated in advance.

We accept card payments (all major credit and debit cards), bank transfer, and cash. Payment is taken on completion of the investigation. For insurance-funded work, we can issue the invoice directly to you for submission to your insurer with the report.