Drainless roof

Drainless roof as an urban management system for extreme weather events.

Starkregen prasselt auf ein Dach
© Lupo /pixelio.de

The drainless roof as a contribution to air conditioning in urban quarters

Avoiding flooding during extreme rainfall events and at the same time using the precious water to cool buildings: These two goals are to be achieved with the drainless roof - or ADa for short. The project is funded under the BMBF's KMU-innovativ funding initiative. The drainless roof developed as part of the project is to be embedded in a rainfall-drainage-free property and neighborhood. To this end, the project team will redevelop and combine various elements designed to increase evaporation performance. These include, for example, innovative substrates and plant combinations.

The core of the ADa technology will be to contribute to flood protection by preventing surface runoff altogether. In addition, neighborhoods and buildings will be cooled by active evaporation. This will make a practical contribution to urban neighborhood air-conditioning and resource conservation.

Supporting decision-makers in implementation

The overall objective of inter 3 is to support decision makers from administration and planning to develop a strategy for the implementation of the ADa technology. The central research question is: How can potential areas for the installation of ADa technology be detected automatically in a selected neighborhood? In order to answer this question comprehensively, a decision support system will be developed to automatically verify the suitability of urban rooftop areas for the implementation of ADa technology.

With the help of the support system, the decision makers shall be able to gain the following insights:

  1. Size of the area available for the installation of ADa technology.
  2. Specific locations of suitable roof areas
  3. Implementation barriers for different types of areas (commercial, residential, public buildings, etc.)
  4. Suitable roof areas for particular combinations of ADa technology

Automated identification of suitable roof areas

The criteria for the decision support system will be developed by the project team in collaboration with the decision makers. Spatial, physical, social, ecological, economic, operational-organizational and legal information will be combined. The selected criteria are to reflect the characteristics of the targeted and thus suitable roof areas particularly well. In order to ensure the fastest and most efficient application of the tool, the support system is to be automated.

The aim is to test the developed support system in 2-3 urban test areas for actual upcoming decisions and to show by first implementations of the ADa technology that and how a practical contribution can be made to the improvement of the microclimatic situation in the neighborhood.

Drainless roof as an urban management system for extreme weather events. (ADa)


Dr. Shahrooz Mohajeri, +49(0)30 34 34 74 40


Bundesministerium für Bildung und Forschung (BMBF)


abc advanced biomass concepts GmbH, Zeobon GmbH, Simon Process Engineering GmbH SIPE


Hansestadt Hamburg


08/2022 – 01/2025