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- Damp hallway: a damaged hot pipe under the floor tiles
A damp hallway, a boiler losing pressure, and two separate faults behind them
Water was pooling under the stairs and the boiler had been losing pressure for two weeks. Pressure testing, tracer gas and thermal imaging found a damaged 15 mm hot pipe under the hallway floor, plus a separate leaking WC valve.
What was happening
Water was pooling on the floor of the cupboard under the stairs, and the hallway and bathroom floors were damp all over. The combination boiler had been losing pressure for two weeks. The water meter showed about 6 litres an hour going through with the internal stop valve open, and nothing when it was closed, so the water was being lost inside the property. It could have been the supply pipe, a WC cistern or the heating.
What the engineer did
The external supply, the internal supply and the hot water pipework were each pressure tested on their own at 4 bar for 30 minutes. Tracer gas put in at the kitchen sink was picked up almost straight away in the hallway outside the bathroom door. Thermal imaging followed the route of the hot pipe to show exactly where to open the floor, and a damp meter showed how far the moisture had spread.
What was found
A damaged section of 15 mm copper hot water pipe under the hallway floor, outside the bathroom door. The damage was from an impact when the pipe was first installed. A leaking ball valve in the WC cistern was a second, separate fault.
What happened next
ADI cut out the damaged section, replaced it with new 15 mm copper pipe and fittings, and pressure tested the repair at 4 bar for 30 minutes with no loss. The hallway floor tiles were reinstated over the renewed pipe. The customer was advised to have the WC ball valve replaced separately.
If you manage rentals
One leak found does not always mean one fault. When a report lists a repaired pipe and a second item still to fix, pass both to the landlord at once, so the second one is not waiting for the next call from the tenant.
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The meter showed a small leak with no water in use. When the flat was converted to a combination boiler, some old hot pipework had been left buried under the bathroom floor, still connected and under pressure.
Rented home: a shower connection hidden behind the wall
The tenant reported a leak from the upstairs bathroom, with damage to the ceiling below and saturated skirting. An endoscope, removed panels and one targeted opening led to a leaking shower-mixer connection.