People often expect a leak investigation to be a person with a moisture meter and an opinion. A proper one is closer to a small piece of engineering: measure, test, rule things out, and write down what was found in a way someone else can check. Here is what that involves and what each tool can and cannot tell you.
Step one: the history
Before any instrument comes out, the useful evidence is yours. When did it start? Does it follow rain, or showers, or neither? Has anything been repaired, repainted or renovated? Are there plans, a waterproofing certificate, previous reports? A leak that appears only after southerly rain and one that appears every morning point in different directions before anyone has measured anything.
Thermal imaging
An infrared camera shows surface temperature. Wet materials cool by evaporation and hold heat differently from dry ones, so damp areas often show as a distinct pattern the eye cannot see. It is fast, covers whole walls and ceilings at once, and can reveal a leak path well beyond the visible stain.
Moisture mapping
Moisture meters measure the electrical properties of a material, which change with water content. Taking readings on a grid across a wall or floor, and recording them, produces a map: where the wettest point is, how the moisture falls away from it, and whether it follows the floor, the ceiling or an external ground line. The pattern is the diagnosis; a single reading is just a number.
Readings are taken relative to a known dry area of the same material, because every material and coating reads differently, and because salt contamination can make a dry wall read wet. Where possible the mapping is repeated after a dry spell or a rain event to see what moves.
Controlled water testing
Where the source is uncertain, water is applied deliberately to one suspect area at a time, in a controlled amount for a set period, while the point where the leak shows is watched. A shower screen, a window, a balcony threshold and a roof flashing are each tested in isolation. This is the step that turns "the balcony leaks" into "water enters at the door threshold on the northern side". It is slower than anything else in the process and it is where most of the certainty comes from.
The report
A useful report states what was observed, what was measured, what was tested and what was concluded, in that order, with photographs and readings attached, and it names the standard the work is measured against where one applies. It should let a builder price a repair, and let a third party such as an insurer, a body corporate committee or a tribunal follow the reasoning without taking anyone's word for it.
- The location and most likely cause of each water entry, with the evidence for it.
- The extent of the moisture affected area, mapped.
- Where the work departs from the relevant standard, if it does.
- What needs to be rectified, described so a contractor can scope it.
- What was NOT found, so the same ground is not covered twice.
HydroIQ does the investigating and the reporting, and nothing else, which is what keeps the findings independent. Where a home owner simply wants the problem fixed and there is no dispute to resolve, our sister company S&S Remedial offers a free diagnostic visit ahead of any remedial work, and that is often the right first call.
Common questions
General information for South East Queensland home owners, not advice about your building or a legal matter. Standards and time limits change; check the current edition or rule before relying on a figure here.