The kit
A damp complaint is rarely settled by one reading. What settles it is the relationship between the air in the room, the surface it touches, and the weather outside. The kit measures all three at once, for a fortnight, so that relationship arrives as a dataset instead of an opinion.
In the box
Why three
It grows where a surface stays cold enough, for long enough, to pull moisture out of the air touching it. Relative humidity on its own cannot show that. A room at 65% RH is unremarkable — the same room with a wall at 11°C and a dew point of 12.4°C is condensing every night, and it is the three readings together that resolve the difference.
Air temperature · relative humidity
Logged in the room the complaint is about. From these two readings the dew point is derived — the temperature at which that air has to give up its moisture as liquid water. It is the number every other reading is compared against.
Surface temperature
Placed on the coldest surface in the room: usually the external wall behind the mould, a window reveal, or a cold bridge at a floor or ceiling junction. Wherever this reading sits below the dew point, water is forming on that wall.
Air temperature · relative humidity
Outside the property, in shade, timestamped to the same clock as the other two. It is the control: it separates a fortnight of exceptional weather from a building that behaves this way in ordinary weather.
The temperature at which air becomes saturated and moisture condenses out of it. It is derived from air temperature and relative humidity, so it moves with both — which is why opening a window on a cold, wet day can cool a wall faster than it dries the room, and make the condensation worse rather than better. Advice of that kind is the reason the finding needs the surface reading and the external reading, not just the room's humidity.
How it works
Five steps, and only two of them happen at the property. The analysis is the same whether the kit went out for a live complaint or has been in place for a year.
Choose a case investigation or ongoing monitoring and the kit is dispatched. Nothing is configured before it arrives — the sensors log from the moment they are placed.
One visit, following the placement guide: ambient sensor in the affected room, surface sensor on the coldest wall, external sensor outside in shade. No wiring, no broadband at the property, and nothing for the resident to install or operate.
A fortnight is the shortest run that shows a pattern rather than a moment. It covers weekdays and a weekend, ordinary occupancy, and enough overnight cycles to tell a room that recovers each morning from one that never does.
Retrieve the sensors and upload the logged data to the case. Readings land against the property, the room and the case they belong to, rather than into a spreadsheet that has to be reconciled afterwards.
The analysis runs over the dataset and produces the finding, the charts behind it and the actions proposed. Add your own logo, the photographs from the visit and your notes, and issue it.
In practice
The sensors log on their own. No app, no account, no readings to write down, and no change to how the home is used — a fortnight of normal occupancy is exactly what the analysis needs to see.
One to place the sensors, one to collect them. Both fit inside the ten working days the investigation itself has to run in.
On ongoing monitoring the sensors stay in place rather than coming back after a fortnight, so a complaint arrives with months of history already behind it. The rest of the sequence is unchanged.
The limits
A fortnight of data can show that a surface sat below its dew point for hours at a time, night after night, in unremarkable weather. It cannot, by itself, say why that surface was cold: a missing cavity fill, a bridged lintel and a dead extractor fan can all draw the same curve. That is what the inspection, the photographs and the assessor's judgement are for — and the report keeps them alongside the readings rather than in place of them.
Order a case investigation and the kit ships with the case already open, or put the property on ongoing monitoring and hold the history before you need it.
