ADI office open Monday–Friday, 7:30am–6:30pmAn urgent leak? Get help

School leak detection in London

London's schools sit on London Clay in the densest concentration of Victorian board school buildings in the country, with no rural sites at all.

11 engineers covering Greater London

Part of ADI’s 23-engineer team across England, Scotland and Wales. This is the total for the Greater London coverage area; individual county staffing and appointment availability are confirmed when booking.

ADI engineer coverage, checked 8 September 2026. See the counties served.

The school estate in London

Open schools in the region
3,111

Across 33 local authorities, teaching 1,400,846 pupils. By phase: primary 1,754, secondary 459, nursery 74, 16 plus 47, all-through 42.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

Special and boarding schools
254 special, 29 boarding

1,667 schools in the region have nursery classes attached, which is where most of the region's early years water use actually sits.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

Schools in rural areas
0

No schools in this region are classified as rural, so every site is on a mains connection inside a built-up area.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

Academy trusts operating in the region
339

913 academies, and 1,123 schools in total sit inside a trust. The largest by school count are Harris Federation (50), Ark Schools (27), United Learning Trust (24).

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

Water wholesalers serving the region
Thames Water, Affinity Water, Essex & Suffolk Water, SES Water

Leakage allowance schemes are set by the wholesaler, but a school's account is with its retailer. Ask your retailer which wholesaler scheme applies, what evidence it needs, and what the repair deadline is, before you commission the repair.

Source: MOSL, Our members: trading parties in the non-household water market (opens in a new tab) ().

Ground and water conditions
London Clay, which shrinks and swells more than almost any other UK soil through drought and recovery, and very hard water from the chalk aquifer.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

School building programmes in the region
The densest concentration of Victorian board schools in the country, built by the London School Board from 1870, alongside major post-war London County Council programmes.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

Largest school site by capacity
Lycee Francais Charles de Gaulle, 3,805 places

In Kensington and Chelsea. A site of this size has a distribution network rather than a single supply run, which changes how a leak is isolated.

Source: Department for Education, Get Information About Schools: all establishment data extract (opens in a new tab) ().

The twelve UK regions arranged as a tile grid, each shaded by the number of open schools it contains, from the four national school registers.Scot2,427NI1,087NE1,220NW3,566Y&H2,421Wales1,440W Mid2,742E Mid2,293E Eng2,824SW2,617SE3,961Ldn3,111

The twelve regions arranged as a tile grid, shaded by open school count. London is outlined. Counts come from the four national school registers, not from an estimate.

What this means for a survey in London

The ground and water conditions above are the practical part. Hard water scales fittings and shortens the life of valves and mixers. Soft water is easier on scaling but less forgiving of some older metallic pipework. Shrinkable clay moves through a dry summer and pulls buried joints apart, and former coalfield ground settles differentially for decades after the workings closed.

None of that changes the sequence: measure at the meter, isolate to a branch, locate from the surface. It changes what we expect to find and where we look first.

Case studies from schools in London

None published yet. Rather than write a plausible-sounding example, this page says so. When ADI supplies a school in this region that is happy to be named, or happy to be described anonymously, it will appear here with the measured loss and what the repair involved.

Arranging a survey in London

Looking for a general leak detection company rather than a school specialist? Our sister directory lists leak detection companies across London. Both sites are published by the same people, which is disclosed on the about page of each.

Sources for this page

Last reviewed . How this site sources and dates its figures.

All twelve regions

0333 567 2619Emergency