Reducing energy while retrofitting the historical building Ryesgade 25 + 30

Ryesgade 25 + 30 is a smart architectural retrofit saving up to 75% of energy

Smart Architectural Retrofitting solves multiple urban challenges within the same project. As the Ryesgade 30 + 25 projects in Copenhagen demonstrates, 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 availability of attractive housing in urban centers.

Ryesgade 30 is a common Copenhagen 5-storey 32 apartment house from 1896, which was retrofitted and completed in  2013. Four new penthouse apartments were added as well as café on the ground floor. Ryesgade 25 is a bit bigger with 42 apartments an 7 new penthouses on top.

The buildings were in both physically and technically unhealthy condition and living conditions for inhabitants were poor.

However, several building features such as the significant and detailed red brick façades had lots of qualities as well as the prime location and the qualities of the area around.

In order to change the living conditions of users, all year comfort levels, as well as reduce the overall energy consumption of the building, several advanced technical improvements have been integrated: Double frame low energy windows, high performance solar cell roof, compact high insulation materials for inner face of exterior walls and roof/basement, decentral low sound heat regain ventilation systems,  IHC (Intelligent Heat Control) and intelligent power control to mention some of the most important.

Investing in the Ryesgade 30 retrofit project more than tripled the owners’ yearly property profit and at the same time reduced energy consumption by 2/3rds. It won the Danish RENOVER award for the best retrofit in Denmark in the year 2013.

Ryesgade 25 is under construction and will be the first DGNB certified (SILVER) retrofit in Denmark.

About author

Retrofitting and transformation of existing residential, public, and private sector buildings. Adapting and developing buildings to future work/living/cultural needs, energy savings, improvement of indoor environment, value optimization and accentuating cultural heritage qualities.

Primary contact
Niels Jakubiak Andersen

Case location

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