Do I need a conductive substrate for electronic integrity testing?

Yes. Both low-voltage wet testing and high-voltage dry testing require a conductive substrate directly below the waterproofing membrane — typically a concrete or metal deck. On timber decks, a conductive medium such as wire mesh or conductive glass felt can be installed during construction to enable EIT. See LRWA Guidance Note 18 (2025) for full substrate requirements.

Can you electronically test a green roof or buried waterproofing?

Not with standard EIT once the overburden is in place. For buried waterproofing, the correct method is electrical field mapping (EFM) — a buried leak location technique that locates membrane breaches to within approximately one metre without lifting the overburden. CIRIA C817 and the GRO Green Roof Code both recognise EIT as a pre-covering QA method and EFM as the post-burial investigation method.

What is the difference between moisture mapping and leak detection?

Moisture mapping tells you where moisture has accumulated within the roof build-up. It does not tell you where the membrane has failed. Leak detection methods such as low-voltage EIT or electrical field mapping locate the actual breach in the membrane. The two are complementary: moisture mapping identifies which areas need investigation; breach-location methods find the source.

Is flood testing safe for flat roofs?

Flood testing carries real risks. A 150mm head of water adds approximately 150kg per square metre of loading — structural sign-off is essential. Water can take many hours to manifest internally, making short test periods unreliable. Flood testing can also cause structural deflection that opens up laps and details. It has a legitimate role in post-repair verification of specific, structurally appropriate areas only.

What qualifications should a roof leak detection specialist hold?

Look for: NVQ Level 3 in waterproofing testing and inspection; RAWTA membership (the Roofing and Waterproofing Test Association); and a demonstrable CV in flat roofing and waterproofing systems. Under the Building Safety Act 2022, appointing an incompetent inspector carries legal liability for duty holders.

Which leak detection method works on a single ply membrane?

For QA of weld continuity at laps and details, vacuum box testing is most reliable. For field-sheet investigation with a conductive substrate, low-voltage wet EIT is standard. High-voltage dry testing also works on non-conductive single ply on conductive substrates. Black EPDM membranes are generally not suitable for EIT due to carbon black content.

How does permanent sensor monitoring differ from leak detection surveys?

Leak detection surveys are point-in-time investigations locating a breach. Permanent sensor monitoring is continuous infrastructure embedded during construction, monitoring moisture in real time and triggering automated alerts. CIRIA C817 specifies permanent monitoring for blue-green roofs; BS 6229:2025 references electronic devices for detecting leaks between inspections.

Does electronic leak detection work in the rain?

Low-voltage wet testing requires a wet surface so rain is not a problem. High-voltage dry testing requires a dry membrane and cannot be performed in wet conditions. Tramex capacitance mapping works in most weather. Infrared thermography requires dry sunny conditions. Tracer gas is best in calm dry conditions as wind disperses escaping gas.

Service

Buried Leak Location

We find where your roof is leaking — without stripping the entire overburden. No guesswork. No unnecessary disruption. Just precision, backed by European sensor technology.

The problem with buried membranes

Water travels. The leak and the symptom are never in the same place.

When a buried roof leaks, the usual response is a procession of contractors, each with a different theory. Strip back here. Open up there. Weeks pass. Costs mount. The leak persists — because on buried membranes, water travels laterally.

Conventional investigation methods are essentially educated guesswork. On a green roof, landscape deck or inverted system, every failed attempt means removing overburden, access costs, and programme delay.

Vector takes a different approach — electrical field mapping that locates the exact membrane breach to within approximately one metre. You open up the right area. You carry out a localised repair. You don’t strip 200 square metres of green roof hoping to get lucky.

How it works

Three steps. One precise location.

From initial inspection to final report — a single, efficient engagement.

Step 01

Site Inspection

We begin with a full site visit — assessing the roof construction, understanding the build-up, and establishing the right investigation strategy before any equipment is deployed.

Step 02

Electrical Field Survey

Using Texplor technology, we introduce a controlled voltage differential across the waterproofing membrane and use specialist survey equipment to detect conductivity anomalies — the signature of a membrane breach.

Step 03

Contour Map & Report

Results are compiled into a contour map that locates leaks to within approximately one metre. You receive a photographic record, survey data, and a written report — everything needed for a targeted repair.

“

Their approach accurately identified numerous leak locations, allowing us to resolve the issues with precision and minimal disruption — much to the relief of both the client and residents. I would highly recommend Vector for similar challenges.

Martin Farrell
Senior Contract Manager, Balfour Beatty
Darley Dale Care Home — multiple longstanding leaks beneath green roofs

Typical use cases

Where we're called in

What you receive

The deliverables

Technology

Exclusive UK access to Texplor EFT technology

Our survey technology comes from Texplor, a specialist in geophysical measurement based in the Netherlands. Vector holds exclusive rights to use their buried leak location technology (EFT) in the UK — it is not available from any other UK provider. We have worked closely with Texplor for years, training together and refining techniques. It is what allows us to find leaks that conventional investigation methods simply cannot.

Exclusive UK Partner — Texplor EFT Technology

Stop the guesswork. Stop the strip-out.

Tell us about the leak. We will locate it precisely, oversee the repair, and come back to verify it is done.