Monitoring of waterproofing and structural moisture protection: The limits of point measurement methods and the need for innovative approaches

The punctual measurement of physical quantities is undoubtedly considered a proven method for characterizing the behavior of components, especially if the material behavior can be assumed to be homogeneous and isotropic. It enables precise recording of specific parameters and provides valuable insights into the behavior of building structures. However, selective measurement methods often reach their limits where unforeseeable, disruptive events, the location of which cannot be predicted in advance, must be quickly detected and localized in order to avoid consequential damage.

This is mainly due to the fact that monitoring methods based on discrete, distributed measuring points are often not representative of the entire monitoring area due to the low density of measuring points. Especially in the case of events such as leaks, cracks or other unexpected damage, the occurrence of which cannot be clearly predicted, punctual measurements can have difficulty locating them in time and accurately.

To meet this challenge, a paradigm shift towards continuous, area-based monitoring is proving to be promising. ProGeo has recognized this and has been developing technologies for more than 30 years that economically enable comprehensive monitoring of even very large objects. These approaches allow the relevant parameters to be continuously recorded across the entire area to be monitored. This not only overcomes the weaknesses of point measurements, but also detects disruptive events immediately and precisely, regardless of where they occur.

The following practical examples illustrate the effectiveness of this approach:

Monitoring of buried plastic seals

The metrological monitoring of buried waterproofing in the environmental protection sector is made possible by the BAM-approved geologger® seal control system. This system is based on an areal recording of the electrical resistance distribution of the monitored sealing. It uses a voltage difference imprinted in the electrically conductive soil layers adjacent to the waterproofing and records the potential distribution that occurs with a grid of measuring points in one of the soil layers.

Thanks to a measuring grid of 5 to 10 metres, which is usually used in practice, the smallest leaks can be located with an accuracy of a few decimetres, regardless of where they occur. This process is now state-of-the-art and is mandatory for certain landfill classes and facilities for handling water-polluting substances.

Real-time monitoring of building waterproofing

The metrological monitoring of green and used flat roofs is implemented by means of the real-time monitoring system smartex mx®, which enables continuous recording of the entire roof area. This system works according to the same measuring principle as the geologger® system, whereby the voltage difference between the wet cover or wear layers is applied to the waterproofing and an electrically conductive contact layer located below the waterproofing.

Changes in the potential distribution in the contact position as a result of leaks that occur are measured automatically and continuously with a matrix of sensor points. This enables immediate detection and precise location of the leak, regardless of the location of the leak in the

Sealing. In addition, the system also provides qualitative location-specific information about the moisture distribution within warm roof structures.

smartex® mx is available in various design variants and is suitable for use with loosely laid, mechanically fastened and fully hot-glued or self-bonded seals.