Conversion of former RAG high-rise building

Dortmund

A place to live and experience

The interaction of working and living promotes vitality in every city center.

Life has shifted to the outskirts of cities, where, in contrast to the city center, generous green spaces are available nearby and the workplace is also easily accessible by car. As a result, the inner cities lost a large proportion of their inhabitants and were filled with work and retail space. Living and working were separated.

The digitalization of workplaces is breaking down this traditional structure. People can work from anywhere, making the traditional office building less important. Working environments are becoming more flexible and location-independent, but at the same time require an attractive range of leisure activities. New mobility concepts are increasingly making it possible to do without investing in a private car.

The conversion of the former RAG high-rise building into a residential building addresses these changes, which affect both cities and their citizens, by finding a solution for both.

A. Location

The building is in a privileged location in the heart of the city. Situated next to the opera house, it has its main entrance on the north-south axis of Hansastrasse. The extensive retail areas, the varied gastronomy and various leisure facilities can be reached on foot in a very short time. The location is very well connected thanks to its proximity to public transport, the subway and the main railway station. Users with their own vehicle can use the existing garage with 121 parking spaces.

B. Concept: a place to live and experience

The building rises like a pyramid. The existing building has structures with deep areas on the first floor and second floor, which are still suitable for commercial use with internal service cores. Our concept retains the commercial use of the first two floors - ideally, the current co-working spaces can continue to be offered - and begins with the conversion to residential space on the second floor. The new residential units are located along the existing corridors, and the flexibility of the office layout is reflected in the new apartment layout, which allows for a range of different sizes and unit types. Loggias or balconies are provided in the apartment layouts to give each resident private access to the outdoors. The roof spaces created by the staggering of the building volume on every other floor are transformed into gardens for the community of residents, which also allow for a concept of curated urban gardening. The building offers interesting views in every direction. The RAG building is no longer just a place to work, but rather a place to live and experience. The reuse of the existing building fabric, the reduction of the ecological footprint by bringing residents back into the heart of the city, the sustainable and social way of life through generous shared green spaces all fit into the current context.

A new use requires a new identity. The RAG building has very formal features with a strong presence - the regular grid of the metal panels with the horizontal bands in front contrasts with the strongly pronounced volume development of the complex.

C. Facade concept

Retention of the existing façade with integration of greenery: the curtain wall with its typical glass elements will be retained. Only the windows will be replaced to allow natural ventilation of the apartments. Individual floor-to-ceiling openings will be created that open up like a “French balcony” to the cleaning corridor and offer the residents a perceived outdoor space. This itself will be planted with climbing plants. In this way, the RAG building is covered with green strips like a tree, making the outer shell appear different depending on the season.

Glass Living Mixed Retail

Data

Preliminary building application

2020

Address

Hansastraße 95
44137 Dortmund
Germany

Client

Aroundtown SA

@55 House Of Business

Dortmund

The new “@55” building is located within the “Stadtkrone Ost” conversion area in Dortmund.

The new building stands on a 20 m high embankment and borders directly on a nature conservation area. The storeys are offset from each other, creating a terraced landscape to the south, which can be converted into additional office space if required. On the north side, the storeys overlap the entrance by up to 12 m, creating a cascading roof.

The loads of the cantilevered storeys are bundled at the top and guided downwards with tension cables that follow the slope of the outer wall. Here, the resulting forces are transferred to the ground via a counterweight (approx. 150 m³ cavity filled with sand).

The storeys are unsupported and undetermined, i.e. uses are not predetermined. The building currently houses a restaurant, a medical practice, offices and an apartment.

The façade is homogeneously covered with horizontally laid profiled glass/structural glass, which is held in a point-like manner. This creates a crystalline structure that gives the building an abstract identity. In some places there are ribbon windows behind the outer skin - here the profiled glass can be rotated around the horizontal axis using a simple mechanism - thus providing an unobstructed view of the surroundings.

Concrete Glass Office Steel

Data