Varuna: Sita & Telekom launch digital roof inspection service

Extreme weather events, increasingly frequent periods of heavy rain and complex roof structures are posing growing challenges for flat roofs. Whilst visible damage is usually detected quickly, water accumulation or damp within the roof structure often goes undetected for a long time. The consequences range from energy losses and mould growth to structural damage to the building.

Traditional roof maintenance relies on regular inspections; however, due to the intervals between them, these do not allow for continuous monitoring. Against this backdrop, Sita Bauelemente GmbH identified a need to monitor flat roofs continuously, automatically and regardless of weather conditions.

Building on this foundation, Sita developed the Varuna solution – a combination of many years’ expertise in flat roof drainage and modern IoT technology. The aim was to create a reliable and practical solution that would function consistently even under extreme conditions. Various sensor technologies and communication

approaches were tested over several years of field trials. However, earlier solutions such as Bluetooth Low Energy or LoRaWAN were unable to meet the requirements for range, stability and energy efficiency in real-world use.

A key factor in the project’s success was the close collaboration between Sita and Telekom. Clear points of contact, technological expertise and a shared understanding of quality enabled the project to be implemented efficiently and in a spirit of partnership.

The combination of industry know-how and IoT expertise formed the basis for a solution that is compelling from both a technical and a commercial perspective.

The Varuna sensors have been specially developed for use on flat roofs. They can withstand temperatures of up to 80 °C, are protected against the elements and are designed for long-term operation.

The rain monitor accurately measures water levels on the roof surface, whilst the hydro sensor detects moisture within the roof structure. Both devices are solar-powered and designed to require minimal maintenance.

Together, they form a coordinated monitoring system that identifies risks at an early stage and provides a reliable data foundation for operators.

Automated data collection replaces regular manual checks and significantly reduces the operational workload. At the same time, it enables damage to be detected at an early stage and prevented.

Real-time data supports informed decision-making and enables predictive maintenance. This increases operational reliability, reduces costs and makes it easier to plan maintenance activities.

Sita is constantly developing Varuna further. Future analytics functions, forecasting models and integration options are set to further enhance the solution’s benefits. It

is already clear that networked sensor technology and IoT are becoming a key component of modern building strategies – delivering greater transparency, efficiency and security.