Lead Pipe Replacement in Kensington and Chelsea

Updated July 2026 · Emergency Plumber Chelsea

First, ownership. You, the property owner, own the supply pipe that runs from the outside stop valve into your home and up to the inside stop valve — that private section is your responsibility to maintain or replace. Thames Water owns the communication pipe from the water main up to the boundary. Knowing where that line sits matters, because it decides who pays for which stretch.

Thames Water runs a free lead pipe replacement scheme that works with that split: if you replace the private lead section you are responsible for, Thames Water will, on an approved application, replace their communication pipe section too — so the whole run ends up lead-free rather than half-and-half. Replacement pipe is laid to standard, and where the old pipe is smaller than the usual 25mm it is typically upgraded to 25mm. It is part of a large programme Thames Water is running across its region.

While a lead supply remains, reduce exposure with simple habits: run the kitchen tap for a short while to draw fresh water through before drinking or cooking, especially first thing in the morning or after the home has been empty, and never drink long-standing water from a lead system. A point-of-use filter certified for lead can help in the interim, but replacement is the real fix.

Applying for the Thames Water side is straightforward if you do it in the right order. First confirm you have lead, either by looking at the pipe where it enters the house beside the internal stop valve or by asking us to inspect it. Then contact Thames Water about their lead replacement scheme before any digging starts, because they will want details of the property and the planned work, and the private section generally has to be renewed to their specification before they replace the communication pipe. Once your side is done, they arrange their part. Terms and timescales are set by Thames Water, so confirm them when you apply.

The private-side job usually means laying a new supply pipe, normally blue MDPE plastic, from the boundary to the inside stop valve. In a Chelsea terrace with a front garden or lightwell this is often done by moling, where a tool drives a tunnel under the ground so paths and planting are not dug up; where there is a basement, vault or solid front area, the route is planned around it. Inside, the new supply connects to a new internal stop valve. Many period homes also have lead or old galvanised steel pipework inside the house, which the Thames Water scheme does not cover; it can be renewed at the same time, and our guides to house repiping costs and copper, plastic and PEX pipes explain the options.

We replace lead supply pipes across the Royal Borough of Kensington and Chelsea and into neighbouring Fulham, where many Victorian terraces have the same lead supplies as Chelsea's. Mansion blocks are a special case: the supply often runs through a shared riser owned by the freeholder, so replacement has to be agreed with the managing agent. Where the work uncovers a leaking or failing buried supply, it comes under our leaking water mains repair service.

On the day, the order of work is simple. We check where the existing supply enters the house and where the outside stop valve sits, agree the route for the new pipe, then either mole or open a narrow trench from the boundary to the entry point. The water stays on until the final connection, so the time you are without a supply is usually short. Inside, we fit a new internal stop valve and, if you ask, a drain-off so the system can be emptied in future. On a straightforward terrace with a front garden the private side is often a one-day job; a long run, a basement or vault, or a solid front area laid in stone takes longer and is planned in advance. Once your side is done, Thames Water renews their section on their own timetable. Our guides to Thames Water leak detection and who owns which pipe and stopcock replacement cover the boundary and the valve in more detail.

Replacing a private supply pipe in a Chelsea terrace or mansion flat can involve moling under a front garden or coordinating with a freeholder and neighbours on shared runs — the kind of access issue we handle regularly. Emergency Plumber Chelsea can replace your private lead pipe and help you line up the Thames Water side. Call 020 3002 6667.

Quick tips

• You own the pipe from the outside stop valve to your inside stop valve; Thames Water owns the communication pipe to the boundary.
• Replace your private lead section and Thames Water may replace their part free under their scheme (application approval needed).
• Run the tap before drinking if you still have lead pipes, especially after the home has been empty.
• Old undersized pipes are usually upgraded to 25mm on replacement — better flow as well as no lead.

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