New Home Plumbing Checks London: What to Do When You Move In

Why Plumbing Checks Matter When Moving Into a London Property

London has one of the oldest housing stocks of any major city in the world. A significant proportion of the terraced houses, Victorian conversions, and Edwardian semis that make up much of the capital were built with lead pipework, which in many cases remains in place today on sections of the supply that were not updated when the property was last refurbished. Even newer properties can have plumbing issues that are not obvious during a pre-purchase viewing: a slow drip under a bath panel, a toilet cistern that fills slowly, or a shower that loses pressure are all issues that tend to only emerge in daily use.

A homebuyer survey will have flagged major structural issues but may not have covered plumbing in detail. A gas safety certificate, if provided, confirms that the gas appliances and flue arrangements are safe, but does not cover the water supply pipework or drainage. Taking time in the first weeks after moving in to carry out a methodical plumbing check is time well spent and can prevent expensive surprises.

Finding and Testing the Main Stopcock

The first and most important thing to locate in any new London property is the main stopcock. This is the valve that controls the entire cold water supply to the property. In a London terraced house, it is typically located under the kitchen sink or in a small cupboard at the front of the property near the front door. In a flat, it may be in the communal area, under the sink, or in an airing cupboard. Turn it off completely and then back on fully to confirm it operates. A stopcock that is stiff, will not fully close, or is dripping around the gland should be replaced before an emergency arises. Note the location of any secondary isolating valves on the supply to the washing machine, dishwasher, and toilet cisterns.

With the stopcock identified, check the water pressure by running a cold tap fully open. London mains water pressure should give a strong, even flow. If the flow is poor even with the stopcock fully open, the supply pipe may be partially blocked by scale or corrosion, or there may be a partly closed isolating valve somewhere on the supply. Persistent low pressure is worth investigating before it becomes a cause of poor shower performance or slow-filling appliances.

Checking for Lead Pipework in London Homes

London properties built before approximately 1970 may still have lead supply pipes on the section of pipework between the water main in the street and the property boundary, or in some cases within the property itself. Lead pipework can be identified by its dull grey appearance, its malleability (it dents rather than scratching cleanly when pressed with a key), and the characteristic bulge at each joint where the pipe was wiped with solder. Thames Water and other London water suppliers provide a free lead pipe check service and can test your water for lead if you are concerned. Where lead is found on the internal supply pipe, replacement with copper or plastic pipework is advisable.

Checking the Boiler, Drains, and Radiators

Confirm when the boiler was last serviced by looking for a service label on the boiler casing or asking the previous owner or estate agent. If no service has been carried out in the last twelve months, book one promptly. Check the system pressure on the boiler gauge and top up if required. Run all taps and observe the drainage speed: slow drainage from a basin, bath, or kitchen sink indicates a partial blockage in the waste pipe that will worsen over time. Flush all toilets and confirm the cistern fills fully and stops cleanly. Check under baths, basins, and sinks for evidence of previous leaks, which may appear as staining, warped cabinet boards, or a musty smell. Prestige Engineers provide new-home plumbing surveys for London buyers and can provide a comprehensive inspection report with recommendations for any work required.