Emergency Plumbing & Boiler Repair · Wandsworth, London
Leak Detection & Repair in Wandsworth, London
The worst leaks are the ones you cannot see: a stain that appears on a ceiling after a week, a damp patch that returns after you repaint it, or a water meter that creeps round while every tap is off. [24HR Boiler Repair & Plumber](/) answers on 07727 932887 at any hour and arranges leak detection and repair through independently owned partner companies across Wandsworth, Putney, Southfields and Earlsfield.
Finding a leak is a process of elimination. The partner company checks the visible pipework, tests the pressure in heating and cold-water circuits, and uses moisture meters and, where needed, thermal imaging or acoustic listening equipment to trace water inside walls and floors. The aim is to open up as little as possible, so you are not paying for plaster and tiles to be removed on a hunch.
Wandsworth's older housing hides leaks well. Victorian and Edwardian terraces in Earlsfield and the Southfields Grid have pipework buried in plaster, running under floorboards and through walls that have been altered several times, and homes built before about 1970 can still contain lead supply pipes. If you replace your private side of a lead supply pipe, Thames Water replaces its own side free of charge.
Repairs follow the Water Supply (Water Fittings) Regulations 1999, which also ban lead in new work. The partner company gives a written quote for the repair before starting, and for a leak affecting a flat below, tells you what to report and to whom.
The cost of a leak is rarely the water. A hidden leak on a cold supply can run for months unnoticed, and the bill that arrives is for the water used plus the damage to timber and plaster. If you have a water meter, checking it before bed and again in the morning, with everything off, is the cheapest leak test there is, and it tells you whether to call us.
What We Do
Leaks We Trace and Repair
Leaks hide in three places: the heating system, the cold supply and the waste pipes.
Heating and Hot Water Leaks
A boiler that keeps losing pressure, a damp patch under a radiator or a wet floorboard near the cylinder suggests a leak on the heating circuit. Because heating water is under pressure when the system runs, small leaks can drip for months. The partner company isolates sections, tests each, and repairs or replaces the failed joint, valve or length of pipe.
Cold Supply and Underground Pipes
A water meter that moves while everything is off, a damp patch in the garden or low water pressure points to a leak on the supply pipe. The partner company traces the route, locates the leak and repairs or replaces the affected length. If lead is found, replacing it to current rules is the sensible fix, and Thames Water deals with its own side.
Waste, Shower and Bathroom Leaks
A stain below a bathroom, a failing shower tray seal or a leaking waste pipe can cause damage for a long time before you see it. Tracing involves testing each fixture and looking at joints and sealants. In converted flats, the leak may be in the flat above, so the partner company advises who to contact.
The Benefits
How a Leak Is Traced
Careful tracing saves opening up the wrong wall.
Isolate and Test
The system is isolated section by section and pressure-tested, which narrows the search without any damage to plaster or floors.
Non-Invasive Tools
Moisture meters, thermal imaging and acoustic equipment find the leak inside a wall or floor so that only a small opening is needed.
Repair, Then Dry Out
Once repaired, the area needs time to dry before redecorating. The partner company tells you what to expect and what to report if the damage reaches a neighbour's property.
Good to Know
Signs of a Hidden Leak
Water leaves clues even when you cannot see the pipe.
Clues Inside the Home
These are the usual first signs.
- A brown or yellow stain on a ceiling or wall that grows over days
- A musty smell or visible mould in a room with no obvious cause
- Peeling paint, blistering wallpaper or bubbling plaster
- Warped skirting boards or lifting floor coverings
- The sound of running water when everything is off
Clues in the Bills and Meter
The numbers can show a leak before the damage does.
- A water bill that rises with no change in how much you use
- A meter that keeps moving when every tap and appliance is off
- A boiler that needs repressurising every few days
- A damp, green or unusually lush patch of garden along the supply pipe
- Low water pressure that appeared suddenly
Why Us
Leak Work Across SW18, SW15 and SW19
Old buildings, hidden pipes.
Terraces With Altered Pipework
Many Earlsfield and Southfields terraces have been extended, converted and re-piped more than once. The partner company is used to tracing pipes that nobody has a plan for.
Putney Villas
Large Victorian and Edwardian villas around Putney Hill have long pipe runs between floors, so a leak can travel a long way from where it starts.
Written Quote, One Number
The partner quotes in writing and invoices directly, and we handle no payment. If something is not right, call us and we chase it.
Leaks rarely come alone. See burst pipe repair for sudden failures, emergency plumbing for the immediate response, and radiator repair & installation for heating leaks. We cover Putney, Southfields and Earlsfield, and all services are listed online.
What Is Leak Detection?
Leak detection is the process of locating the exact source of a water leak that is not visible, so that it can be repaired with minimal disruption. The methods range from simple isolation and pressure testing to moisture meters, thermal imaging cameras, tracer gas and acoustic listening equipment that picks up the sound of water escaping from a pressurised pipe.
Once the leak is found, it is repaired to the Water Supply (Water Fittings) Regulations 1999, which require fittings and materials to be of suitable quality and installed so as to prevent waste, misuse and contamination. The repair is tested before the opening is closed, and any wet materials are left to dry out before they are covered over.
What Affects the Price of Leak Detection
Finding the Leak
A leak at an accessible joint costs little, while one buried in a wall or under a floor needs equipment and time. Published London guides put standard call-outs at roughly £40 to £100, with specialist tracing and the repair on top.
Opening Up and Making Good
Tracing keeps openings small, but plaster, tiles and flooring may still need repair afterwards. The partner company's written quote should say whether making good is included or priced separately.
Frequently Asked Questions
How do you find a leak behind a wall?
The partner company starts by isolating sections of the system and pressure-testing them, then uses moisture meters, thermal imaging and acoustic listening equipment to pin down the location. That lets them open a small, accurate hole rather than a large exploratory one. Once found, the leak is repaired and the opening made good, with the quote agreed before any repair begins.
How much does leak detection cost?
Prices depend on how hard the leak is to find and how much of the property is involved. Many leaks are traced at a standard call-out and hourly rate, while specialist equipment adds to the cost. Published London guides put standard call-outs at roughly £40 to £100. The partner company gives a written quote before starting, and we do not promise a price on the phone.
My water meter moves when everything is off. What does that mean?
It usually means water is escaping somewhere between the meter and your taps, which could be a leaking supply pipe, a running toilet cistern or a faulty tap. Check that no appliance is filling, then look for a damp patch in the garden or under floors. If the meter still moves, call us, because an undetected leak wastes water and can undermine foundations.
Are lead pipes still a problem in Wandsworth?
Homes built before about 1970 can still have lead supply pipes, which were standard through the Victorian era. The pipe from the street to your boundary belongs to Thames Water, and if you replace your private side, Thames Water replaces its side free of charge. The Water Supply (Water Fittings) Regulations 1999 ban lead in new work.
Water is coming through my ceiling from the flat above. What should I do?
Shut off any water you control, switch off lighting circuits near the leak if it is safe to do so, and contain the water with buckets. Contact the neighbour above and the managing agent, take dated photographs of the damage and keep receipts. The partner company can identify whether the source is a private pipe, a shared pipe or the roof.
Can a leak damage my property's structure?
Over time, yes. Persistent leaks can rot timber joists and floorboards, cause damp and mould, and in underground leaks, wash away soil and undermine foundations. Early detection is worth much more than the cost of a trace. A damp patch that returns after drying out is a signal to have the pipework checked. Ask the partner company to photograph the damage found, because the images help any later claim or dispute.
How long does a leak repair take?
A leak at an accessible joint can be repaired in an hour or two, while one buried in a wall or under a floor may take half a day or more, including opening up and making good. After repair, damp areas may need days or weeks to dry before decoration. The partner company estimates the time in the written quote.
Do I need to turn off the water while waiting?
If water is actively escaping, yes. Close the main stopcock, usually under the kitchen sink or near the front door, and open the cold taps to drain the pipes. Switch off the boiler and immersion heater if a hot-water pipe is involved. Then call 07727 932887, and the partner company will take it from there.
Can a leak be hiding in my heating system?
Yes. A boiler that needs topping up regularly, or a damp patch near a radiator, suggests a small leak on the sealed circuit. The partner company pressure-tests the system and checks joints, valves and the boiler itself. See central heating repair and boiler repair for how those faults are handled. If the boiler is losing pressure, do not keep topping it up without asking why, since the water has to be going somewhere.
What if the leak is outside my property?
A leak on the pipe between the street and your boundary is Thames Water's responsibility, while the pipe from the boundary to your stopcock is yours. The partner company can identify where the leak is and advise who should deal with it. If it is on Thames Water's side, report it to them and keep the reference number.
Is thermal imaging always needed to find a leak?
No. Many leaks are found by isolating sections and pressure testing, or by simple inspection of joints and appliances. Thermal imaging and acoustic equipment come into play when the leak is hidden inside a wall, floor or ceiling and cannot be found by those methods. The partner company chooses the least invasive method that works, and tells you before using specialist equipment.
What should I tell my landlord or managing agent about a leak?
Give the date you noticed it, where it appeared, any damage to belongings and the steps you took to stop it, with dated photographs. Ask them to confirm whether the leak is from a private pipe, a shared pipe or the roof, and who is arranging the repair. Keep copies of all messages. The partner company can describe the fault in writing if that helps.
