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100 climate solutions from Danish Municipalities


The renovation of a 100-year-old property in Ryesgade raises the bar for sustainable urban retrofitting with the first residential DGNB certification.

Ryesgade 25 in Copenhagen demonstrates that it is possible to reduce energy use drastically when retrofitting a historical building, while offering increased comfort, enhanced user control of the indoor environment – and increasing the availability of attractive housing in urban centers. The building is the first residential property in Denmark to have received DGNB certification. The renovation is carried out with a wide range of thorough energy improvements, heat regain ventilation systems, a high performance solar cell roof and climate- proof elements to manage cloudburst and rain water.


With buildings accounting for nearly 40% of global energy consumption, renovation and retrofitting of the built mass is a prerequisite for achieving sufficient CO2 reductions to handle climate change. Overall, the renovation of Ryesgade 25 results in a 71% CO2 reduction, making the project a strong example of how to achieve high energy savings through well thought-out, holistic solutions. By involving residents in the development process, it has been possible to collect data on energy consumption and indoor climate.

The part less worthy of preservation - a worn and unused ceiling - has been replaced with new roofs and new, sustainable housing.

How the Global Goals are addressed

Affordable and Clean Energy

The building's new integrated 146.4 m2 solar system covers the entire property's electricity consumption, promoting sustainable consumption for the benefit of building owners and the climate.

Sustainable Cities and Communities

During the renovation, the unused attic space and courtyard area have created additional apartments that contribute to densification of the city and sustainable urban development.

Climate Action

The retrofitting project has integrated climate adaptation elements such as green roofs and a secured basement and ground floor, enabling the property to handle cloudburst and heavy rain.