Cases – Water, Leak detection

Leak detection in Lambeth palace

The damage suffered as a result of leaking pipes should not be underestimated - a 0.5mm leak could lose 20 litres of water every hour. Even if a leaking pipe is noticed, the cost and disruption associated with locating the source could be considerable. Too often walls, floors and even other pipes are unnecessarily damaged and there are no guarantees that the leak will be found as it is very often some distance from any signs of any water damage.

Polygon employs a number of methods to detect leaks in scenarios as diverse as a small scale domestic pipe leak through to major pipeline constructions. Our methods include 

  • Acoustic profiling
  • Thermography
  • Tracer Gas
  • Correlation.

In the event damage is suffered, Polygon has the necessary skills to deliver a rapid, robust, cost effective and efficient response. Our ‘trace and access’ service remediates the leak, makes it safe and prepares the area for re-instatement. 

This is what happened

Lambeth Palace is the official residence of the Archbishop of Canterbury. It features over 600 rooms and contains around 300 radiators. 

In the coldest December on record to date, a leak caused around 20,000 litres of water to be lost from the central heating system. Inevitably the system then stopped working. Heating engineers were initially called in but after a number of days of investigation they were unable to find the source of the leak. On 23rd December, Polygon was appointed to detect the leak.

This is what we did

Together with the heating engineer, the Polygon technician quickly identified that one of the four boilers serving the Palace was losing pressure. This logically enabled them to isolate the broad area of the leak, as each boiler served a specific circuit. 

The area affected included the crypt, administration offices, toilets, art gallery and stone floored library. Tracer gas was specified as the fastest and most effective technology to trace the leak and with the limited reserves of gas available so close to Christmas, the technician was able to detect a slight trace in the under floor void which indicated a possible leak in the foyer to the crypt. 

Three technicians and a large supply of tracer gas were then deployed to the site. Using a combination of gas, acoustics and videoscope, the technicians were able to detect the precise location of the leak within three hours.


  • Non-destructive testing solution ensured that this historic building was not damaged and excavation work was minimised
  • Increased detection speed resulted in less interruption and associated costs