Leak detection

When conducting this non-destructive test, we use an electrode brush to transfer high-voltage electricity across the entire surface of the roof. If the roof cladding is damaged, an electric circuit will be completed, and sparks will be discharged. This will cause the device to emit an alarm signal. Depending on the device used and the structure of the roof, this test can only be conducted on completely dry or slightly moist non-conductive roof cladding.

In a smoke test, we blow smoke below the roof cladding, which will become visible at certain locations. We expect to see smoke at some locations, but not at others. Based on an analysis of the visible smoke, we can assess whether these locations are the cause of the leaks. This test can be used on roofs where the smoke can travel between the underlying structure (insulation) and the roof cladding.

This non-destructive low-voltage test uses the vector mapping or earth leakage method to find the location of damage. The conductive properties of water provide a medium through which electricity can pass, enabling the user to find the location of leakages. Leakages in the roof membrane allow water to permeate into the structure of the building, causing a short circuit. The voltage difference between two test probes can lead the user to the location of the leakage. This test can only be used on wet, non-conductive roof cladding.

In this test, we measure the surface temperature of the roof cladding using a thermographic camera. Since wet insulation is less effective than dry insulation, a difference in the surface temperature of the roof cladding can be a sign of moisture infiltration in the roof structure. The location and scope of the problem can be identified using this method. Zones where the roof insulation has been affected can be identified using this method.

The presence of moisture in the roof structure can be detected using non-destructive moisture meters. The location and scope of the problem can be identified using this method. Zones where the roof insulation has been affected can be identified using this method.

All the methods set out above are tools used for investigative purposes, but require the correct interpretation of the results. A thorough knowledge of the requirements of the WTCB and manufacturers, construction details, the thermal operation of the building and, above all, common sense are of crucial importance for this.