How to prepare your store for a leak detection visit

The engineer arrives, and twenty minutes later the store manager is still hunting for the plant room key. The centre’s security desk has no record of the visit, and nobody can say where the water meter is. A good part of the first hour of a leak survey can disappear like that. Some preparation the day before gets it back, and it means less disruption on the shop floor.

The paperwork worth finding first

You will not have all of this. Every item you can find saves the engineer working it out on site.

What to have ready	Why it helps
Water meter location and serial number	Dŵr Cymru Welsh Water points out that both are printed on your bill, and that the meter is usually in the footpath outside the premises.
Two meter readings, with times, taken with all water use off	Confirms the loss is real and gives a rough rate before anyone opens a floor.
The last few water bills	Shows roughly when consumption changed, which helps date the leak for your insurer or water retailer.
Drawings, fit-out plans or O&M manuals	Pipe routes on paper narrow the search. As-built drawings from the last refit are the most useful.
The asbestos register	Needed before anyone drills, lifts floor tiles or opens a ceiling.
Dated photographs of the damage	Records what the leak did before it was found and fixed.
Your lease, or the name of whoever handles repairs	Tells you who pays for the repair and who should approve any opening up.

On asbestos, HSE’s guidance is blunt. If a building was built or refurbished before 2000, assume it contains asbestos, and any work that disturbs the fabric of the building where asbestos could be hidden needs a more intrusive survey before it starts. If you have a register, have it out on the counter. If you do not, tell us when you call to book.

Find the stop tap before the engineer arrives

The main internal stop tap is normally close to where the supply pipe enters the building. WaterSafe’s advice is to check regularly that it works but never to force it. During a survey the engineer will often want to turn it off to test whether the loss is inside or outside the building, and a seized valve slows everything down.

Note the other isolation valves too: the ones under the washroom basins, on the feed to the coffee machine, on water-fed chillers and on the cleaner’s sink. A photo of each on your phone is enough.

In a shopping centre or a parade with a shared supply, ask centre management which valve and which sub-meter serve your unit. Some units share a valve with their neighbours.

Keys, access and neighbours

Leaks ignore lease lines. Water from a pipe in your unit can surface next door, and a stain in your stock room can come from the floor above. Before the visit, sort out:

Keys to the plant room, boiler cupboard, risers, roof hatch and any locked stock rooms.
Clear space around the meter and stop tap, and away from walls, ceiling voids and floor areas the engineer may need to reach.
Neighbouring units. If the leak could be in or under the unit next door, ask the neighbour or the landlord for access in advance.
Centre management permission. Many centres want notice of every contractor, a named contact on site and sometimes risk assessments and method statements before work starts. Ask what yours needs.
Parking and a loading bay for a van full of equipment.

Keeping the shop trading during the survey

Our methods are non-invasive. The engineer finds the leak from the surface, using listening equipment, a thermal camera and tracer gas where it is needed, so there is usually no digging and no lifting of floors to find it. That is why many shops keep trading while the survey goes on.

What staff and customers might notice:

An engineer with headphones and a listening probe working along a floor or wall. They may ask for music to be turned down or a nearby machine paused for a few minutes, because acoustic listening works best with little background noise.
A thermal camera pointed at floors, walls and ceilings. It takes pictures and touches nothing.
Equipment at the meter or stop tap, and a small cordon with wet floor signs if the engineer needs to work in a customer area.

The part that can affect trading is testing the supply. To confirm where water is being lost, the engineer may need to isolate the water to all or part of the unit for a spell. While it is off, washrooms, drinks machines, water-fed chillers and cleaners’ sinks will not work. How long that takes depends on the building and on what the tests show, so decide beforehand what staff will do if the customer toilets are out of use for a while, and brief the team.

HSE’s brief guide to using contractors expects the client and the contractor to share information about risks, agree how those risks will be controlled and co-operate while the work goes on, including any permits to work. In practice, tell us about alarms, lone working rules, permits and restricted areas. If your centre runs a contractor induction, let us know how long it takes so the visit allows for it.

What happens on the day

A visit usually follows the same order.

Confirm the loss. A meter test or pressure test shows whether water is escaping and roughly how fast.
Narrow it down. Closing valves section by section shows which part of the pipework is losing water.
Pinpoint. Depending on the pipe and the floor, the engineer uses acoustic listening, thermal imaging or tracer gas to find the break. Our how it works page explains each method.
Mark and agree. The engineer marks the spot and explains what opening up would involve before anything is disturbed.

Where the repair is straightforward, we aim to find and repair on the same day. Whether that happens depends on access, materials and what the leak turns out to be, so allow for the chance of a second visit.

If water is actively escaping, set up a cordon and wet floor signs around the area and keep water away from sockets and equipment. If water has reached the electrics, keep people away and call an electrician.

What you should have when the engineer leaves

Our surveys come with an insurance-ready report. File it together with:

the repair invoice
photographs of the leak and of the meter readings
at least two actual meter readings taken after the repair, two weeks or more apart

Those last two points matter if you plan to ask your water retailer for a leak allowance. In England’s business water market, MOSL’s customer guidance asks for evidence that the leak has been repaired, such as the repair bill and two actual readings at least two weeks apart, and says photographs of the leak and the meter reading will help the claim. In Scotland or Wales, ask your supplier how its leak allowance works. If you are also claiming on your property insurance, our insurance claims page explains what insurers usually ask for.

A checklist for the day before

Meter found, two readings taken and photographed
Stop tap located and checked, without forcing it
Drawings, asbestos register and recent bills to hand
Keys to the plant room, risers and roof hatch
Centre management and neighbours told, and any induction arranged
Staff briefed on what they might notice, including a possible spell without water
A named person on site who can make decisions

Not sure whether you need a visit at all? Call us on 0333 567 2615. The number is also on our contact page, and we have 25 engineers working across England, Scotland and Wales.

Frequently asked

Do we have to close the store for a leak detection visit?

Usually not. Our methods are non-invasive, so there is normally no digging or lifting of floors to find the leak, and many shops keep trading during the survey. You may need a small cordon around the work area, and a spell without water if the supply has to be isolated for testing.

The leak might be in the unit next door. What should we do?

Tell the landlord or centre management the same day and ask for access to the neighbouring unit before the visit. Water travels along pipe runs and under screeds, so the engineer may need to follow the pipework through shared areas to find where it is actually coming from.

Should we clean up the damage before the engineer arrives?

Make the area safe and stop further damage, but photograph everything first. Staining, lifted flooring and wet patches help show where the water has travelled, and dated photographs support an insurance claim or a leak allowance request.