Verified leak detection engineers across Croydon — covering CR0, CR2, CR5, CR7, CR8 plus SE25 and the Croydon portion of SW16. Find directory-listed engineers below.

✅ Checked before listing — identity, insurance, trading presence, Gas Safe (where relevant).
How we verify →
✅ Workmanship guarantee badges on listings — 1, 3, 6 or 12 months

Leak detection engineers set their own fees and may deduct detection from repair if both are booked — confirm before booking.

Contact verified leak detection engineers in Croydon ↓

---

Every listing is verified at time of listing — Gas Safe registration checked against the Gas Safe Register where applicable, evidence of public liability insurance checked, business identity and named contact validated.

Non-destructive tracing is used to locate leaks before opening floors or walls where possible:

• acoustic listening
• thermal imaging
• tracer gas
• moisture testing

Detection is a paid diagnostic step. Once located, simple repairs may be done on the same visit; bigger jobs are quoted separately — ask whether the detection fee is deductible if the same engineer does the repair. No call centres, no middlemen — you contact the engineer directly and agree scope and price before booking.

Before any engineer begins gas work, ask to see their Gas Safe ID card and check the back for the specific work categories they are qualified for.

---

Who’s responsible for what — supply pipes and internal plumbing

Water leak responsibility depends on where the leak is. Getting this wrong can mean paying for a job your water company would have handled.

Who is your water company in Croydon? Croydon Council confirms Thames Water supplies clean water to the majority of the borough, while SES Water (Sutton & East Surrey) provides clean water to the southern part of the borough.⁷ Check your water bill or your supplier’s postcode checker if you are unsure. Sewerage and public sewer responsibility across all Croydon postcodes sits with Thames Water.⁷

Your responsibility as a homeowner:

Thames Water confirms that as a homeowner, you’re responsible for the water supply pipe running from the property boundary into your home — usually under your garden or driveway — and all your internal pipes, appliances and fittings (toilets, taps, showers, water tanks, washing machines).² SES Water guidance applies the same homeowner-responsibility principle within its supply area.⁸

Your water company’s responsibility:

Thames Water is responsible for the water mains and the communication pipe linking your supply pipe to the water mains, across most of Croydon.² SES Water has equivalent responsibility for its supply area in southern Croydon.⁸ If you see a leak in the road or pavement, report it to YOUR water provider, not the one supplying the property next door — Thames Water on 0800 316 9800 (majority of Croydon) or SES Water on 01737 772000 (southern Croydon, 24/7). Croydon Council confirms that leaks outside the property boundary must be reported directly to your water provider.⁹

Shared supply pipes: Thames Water confirms that where a single supply pipe serves two or more properties (common on terraced streets), the properties share joint responsibility for maintaining the shared part of the pipe.³

Tenants: Thames Water confirms that if you’re a tenant, your landlord is responsible for fixing leaks² — report the leak to your landlord or letting agent in writing as soon as possible.

---

Repair deadlines if your water company confirms a leak

Repair deadlines differ depending on which water company supplies your address.

Thames Water (majority of Croydon): If Thames Water confirms a leak on your property, they typically ask you to arrange repair within four weeks.¹

SES Water (southern Croydon): SES Water states that its Waste of Water Notice gives you 14 days to take action and keep SES updated.¹² Always follow the deadline stated on the notice from your own water company.

If the leak isn’t repaired within the deadline, water undertakers have powers to act under Section 75 of the Water Industry Act 1991, including carrying out the repair and recovering the cost from the property owner. In an emergency, the water company may also turn off the supply until the leak is repaired.¹

In practical terms, the deadline is a prompt to act — not a reason to panic. Book a leak detection engineer, get the location confirmed, schedule repair, and if you’re waiting on parts or access, tell your water company.

---

Leak detection methods — what the engineer actually does

Leak detection often starts with non-destructive tracing methods — used to locate the leak before lifting flooring, taking down walls or excavating ground where possible.

• Acoustic listening equipment — amplifies the sound of water escaping from a pipe under pressure. Effective for supply pipe leaks and larger internal leaks.
• Thermal imaging — detects temperature differences where water has cooled or warmed an area. Good for hot-water leaks under floors and central heating leaks.
• Tracer gas — a non-toxic gas pumped into the pipe escapes at the leak point and is detected above ground. Often used for supply pipe leaks under driveways or lawns.
• Moisture meters and damp surveys — identify the wettest point in a wall or floor when the visible symptom (a damp patch) is not at the source.
• Pressure testing — isolates sections of pipework to confirm which branch is losing water.

Many leak detection visits include a written report identifying the location and likely cause, which can be used to plan repair or support discussions with insurers, landlords, managing agents or water companies. Repair is often quoted separately — ask whether the detection fee is deductible from repair costs if you book the same engineer. If the detection is being arranged for a third party, confirm in advance what documentation the engineer will provide.

---

Croydon housing stock — practical context for leak detection

The practical context of a leak detection job differs widely by Croydon property type. The notes below are general observations to help frame a call to an engineer — your engineer’s site visit will confirm what your specific property actually has.

Pre-1914 Victorian and Edwardian terraces — Thornton Heath CR7, South Norwood SE25, Norbury SW16, Addiscombe CR0, parts of West Croydon and Selhurst SE25. Older terrace stock can retain a mix of original copper, later imperial-to-metric retrofit work, and patched repair sections going back decades. Stopcocks are not always where you’d expect — in older terraces the internal stop tap can be under a kitchen sink, in a hall cupboard, under floorboards or sometimes outside the property in a small chamber. Acoustic listening and tracer gas are commonly the most effective methods for older terrace supply pipe leaks given the variable pipe materials.

Inter-war semis and 1930s housing — Purley CR8, Coulsdon CR5, Sanderstead CR2, parts of Shirley CR0 and Selsdon CR2. The semi-detached belt across south Croydon typically has supply pipes running under tarmac or block-paved driveways — supply pipe failure under the driveway is a common Coulsdon and Purley leak pattern. Excavation costs vary depending on driveway type; ask the engineer for a making-good quote alongside the repair quote.

Post-war estates and tower blocks — Selhurst SE25, New Addington CR0, Shrublands CR0, parts of central Croydon CR0. Council and ex-council estate flats commonly share risers and have communal supplies — leak responsibility may sit with the council or managing agent. Always check with your housing officer or managing agent before instructing a private engineer.

Modern flats and town-centre regeneration — East Croydon CR0, town centre CR0, Saffron Square CR0, Ruskin Square CR0. New-build flats around East Croydon typically have planned plumbing risers, manifold systems and isolated branch supplies, making zoned isolation easier but requiring managing-agent consent for any work affecting communal infrastructure.

Hard water across all Croydon postcodes. Both Thames Water and SES Water supply areas covering Croydon are classified as hard water — Thames Water confirms hard water can lead to limescale build-up on household appliances and fittings.⁴ Over time, scale and internal corrosion can contribute to wear in fittings, tap washers, and connection points on appliances and cylinders. If your property has had repeated issues on hot-water fittings or appliances, ask the engineer whether scale may be a contributing factor.

Shrink-swell clay across Greater London including Croydon. The British Geological Survey notes that clay shrink-swell can affect building foundations, pipes or services¹⁰ — a factor to raise with any engineer investigating a recurring underground leak, particularly in areas with mature trees nearby.

---

Council tenants in Croydon — leak repair route

If you live in a Croydon Council home, leak repairs go through the council, not a private engineer.

Call 020 8726 6101 for emergency repairs — the contact centre operates 24 hours a day, 365 days a year.⁵

Croydon Council’s repair priorities classify electrical faults caused by serious plumbing leaks, burst plumbing or flooding that cannot be stopped by turning off the water supply, and serious roof leaks where immediate damage is being caused to the inside or structure of the property as emergency repairs — these will be attended to within 4 to 24 hours depending on the risk identified.⁵ Containable leaks — for example a leaking boiler or radiator where the leak can be contained, or a leak to a sink, washbasin or bath where the leak can be contained — are classified as urgent repairs and attended to within 5 working days.⁵

---

Private tenants in Croydon — landlord obligations

Leaks in a rented property are the landlord’s responsibility to repair. Thames Water confirms that if you’re a tenant, your landlord is responsible for fixing leaks.² Broader landlord repair duties for installations for water, gas, electricity, sanitation, space heating and heating water sit under Section 11 of the Landlord and Tenant Act 1985.¹¹

Report the leak to your landlord or letting agent first, in writing.

Croydon Council advises private tenants that for an urgent repair they should contact their landlord or agent immediately and follow the call up with a letter or email.⁶

If your landlord does not respond or gives an unreasonable response, contact Croydon Council’s Private Sector Housing Team on 020 8760 5476. The council uses the Housing Health and Safety Rating System to assess the hazards and risks in your home and, if they are serious, may be able to take action to get the landlord to complete work.⁶

Keep photographs, texts and emails — the council will ask to see evidence of what you reported and how your landlord responded.⁶

---

What leak detection costs in Croydon

Indicative estimates based on recent London jobs and market observations (2025–2026), not regulated rates — no official pricing data exists for private leak detection. Always confirm pricing before work begins. Actual costs vary by access, method required, property layout and whether repair is included. VAT may apply.

Service	Typical range (London)
Internal leak detection (acoustic/thermal)	from £250
Supply pipe leak detection (external)	from £300
Full-property survey (multiple methods)	from £450
Repair of internal leak (simple, accessible)	from £150
Repair of supply pipe leak (excavation)	from £800
Supply pipe replacement (damaged pipework)	from £1,500

Confirm whether the detection fee is deductible from repair cost if the same engineer carries out both. Ask whether the quote includes making good (reinstating driveway, flooring, plaster).

See the full London Plumbing Costs Guide →

---

---

Frequently asked questions — Leak Detection Croydon

---