Parameters:

Why use CONTROFOIL conductive layer?

 

The High Voltage Electronic Leak Detection or ,,spark test,, only works if the substrate under the waterproofing layer is electrically conductive. For example, damp concrete, sufficiently wet roofing layers (especially geotextile) or there is CONTROFOIL in the roof.

 

The disadvantage of roofs without a CONTROFOIL detection layer is that sufficient water must enter through the roof leaks before measurement to soak the roof layers, thus rendering them electrically conductive. Otherwise the holes cannot be identified. This requires first letting the roof layers be damaged by water and moisture and only then looking for the causes. So only holes that have already leaked through can be identified.

 

Example without CONTROFOIL detection layer: the investor asked for an inspection of a new roof just completed with new dry materials. The investor needs to test the roof as soon as possible. It has not yet rained on the roof so they are waiting for rain. The investor needs to be explained what the situation is:

1. Until the actual inspection, the roof layers (under the waterproofing) must not dry out in order to conduct electric current.

2. Little water can flow into the roof through the tiny holes and perhaps manage to evaporate. Tiny holes may not be found.

3. The surface of the roof must be dry in order to measure.

4. If new holes are created just before the measurement that have not already leaked through, these holes will not be found.

5. If, by the time of measurement, the roof layers (under the waterproofing) have dried out or have reduced their moisture content necessary for conducting electricity. nothing will be found!

Conclusion: You can see for yourself the many disadvantages and effects that then make the spark test just a "show". The roof must first be damaged by moisture and only then checked. But be careful, the tightness was checked and not the moisture that remains in the roof.

​

Example with the CONTROFOIL detection layer: The investor wants to check the roof with new dry materials and with the CONTROFOIL layer, which is still electrically conductive. The roof does not have to be damaged by moisture first and then checked for tightness

1. Holes will always be found. Whether they are new (created now) or earlier.

2. Electrical conductivity is the same everywhere and forever. There is no risk of it disappearing in warm weather.

Conclusion: The test is done responsibly and well for the first time. The roof was measurable but may not have been damaged by moisture. Measurement certainty, electrical conductivity certainty, measurement reliability.

​

Will the flood test help?

The amount of water that passes through a leak in a flood test is certainly higher than in rain. But beware! The amount of water that enters through the holes can be enormous. The water from the flood test will then leak out of the roof for up to a year. So using a flood test to make a spark test work afterwards is an unnecessary gamble. If you really need to prove to an investor that your roof is tight I recommend a flood test only after a good quality spark test with a CONTROFOIL detection layer in the roof.

​

​The solution is to hand over the roof (after its completion) by performing a control test and issuing a protocol on integrity. However, quality control, e.g. using the HVET spark test, requires ensuring conditions in the form of a conductive substrate under the flat roof covering. In practice, however, there is no conductive layer under the covering (separation geotextile, EPS polystyrene, mineral wool are non-conductive materials for electric current).