JoJo - attic renovation in Copenhagen

Location and History
The JoJo complex is located in the Nørrebro district in the center of Copenhagen. It owes its name to its shape, as from a bird’s eye view it resembles the letters of the word "jojo" – the complex consists of two semicircular and two circular buildings.

The original neoclassical complex was designed and built in the early 1920s as part of a broader urban development plan aimed at creating affordable and relatively modern apartments, thereby partially satisfying the high demand for housing at the time. Over time, the JoJo complex became the largest collection of cooperative apartments with 516 residential units and more than 56 staircases leading from the street level.

Concept
In early 2002, the residents decided to undertake an extensive renovation project of the complex with the intention of renovating all roof areas, which were already in a very dilapidated state. However, it soon became clear that the project was a great opportunity to convert the unused space in the attic and create new apartments with a magnificent view of Copenhagen. The renovation plans needed to be reconciled with the budget allocated for the refurbishment. The renovation was subject to oversight by the authorities responsible for maintaining the historical character of the site and the buildings.
The final shape of the new roof and the new apartments were also influenced by the local community's requests regarding the arrangement and size of the roof windows. According to the architectural design, VELUX roof window assemblies, arranged in so-called studio setups, were chosen.

Goals and Collaboration
The general designer of the building was the design studio SBS Byfornyelse, which also conducted engineering work and provided authorial and technical supervision during the construction process.

In the planning stages, it was important that the residents lived in the building throughout the renovation process. Although they could make many decisions as owners of the complex, some issues had to be addressed directly with the relevant city authorities responsible for protecting the historical character and value of the old buildings in Copenhagen. The final decision regarding the shape of the roof, dimensions, and materials used always rests with the city office. Early discussions and meetings with the building's residents were attended by experts from VELUX, who talked to the builders about daylighting issues, roof window options, and proposed the most suitable solutions specifically for their building.

Interior and Exterior
The apartments located on the 4th and 5th floors (attic) are connected by a staircase that, in some cases, leads up to the 6th floor. The size of these apartments has effectively doubled due to the VELUX roof windows, which provide sufficient daylight and direct contact with the sky. The only reminder of the original design is the simple beam braces connecting to the entire building. In the part of the roof facing the courtyard, a large studio window composed of six VELUX roof windows was installed. On the street-facing side, a dormer with a small French balcony was built.

Materials
The residents' primary requirement was the use of only the highest quality guaranteed materials with a lifespan of at least 20 years. The city insisted on the use of red tiles and zinc flashing. Given that some residents could not afford the roof renovation for financial reasons or did not feel the need to expand their apartment, the roof in some areas was only prepared for such future modifications, i.e., the structure of the building was adapted, and preparatory work was done such as replacing the roof insulation and roof windows. Now, only staircases and interior modifications remain to be built. This approach preserved the overall homogeneity of the complex and its architectural beauty.

Frank Engelbrecht Jensen