Half-Long Charles inner-city densification development, Ludwigsburg, Germany

Trio of residential & office buildings

With the objective of inner-city densification, an ensemble of buildings was designed by Steimle Architects for a site near Ludwigsburg’s train station on Karlstrasse. The centrally located gap between the surrounding buildings and the adjoining unpleasant backyard with parking spaces has been transformed and upgraded into a redefining, identity-shaping place.

Revitalisation of an urban brownfield site

In the 1970s, there was an urban development plan in Ludwigsburg that provisioned for taller buildings in four central locations. These were partly completed, but also came under criticism. The site remaining undeveloped for years. Ultimately, the proposed number of floors for the tallest building on Karlstrasse was halved, which meant that the 'Long Karl' quickly became colloquially known as 'Half-Long Charles'.

The brownfield site was a classic backyard that was used as an inefficient parking lot. Steimle Architects recognized the potential of the site and set themselves the goal of maximising its potential.

A connecting plinth base

The ground floor unites the three separate multistorey blocks, whilst differentiating itself from them in terms of both size of openings, and facade design. The roof of the plinth provides an elevated communal open space, an inner courtyard that creates a central focal point.

As a differentiation in use and as a response to the urban setting, it was important to the architects to design the ground floor with a contrasting material that stands out from the taller buildings rising above it.

Aesthetic uniformity of storey & roof levels

In the classic Wilhelminian-style house, the facade and mansard, or loft storeys are visibly separate. Usually, the servants lived in these worst rooms on the top floors, not least because of the heat in summer and the difficulty of access to them.

Nowadays, living on the upper floors offers far more desirable experience with better lighting and better views. For this reason, a sloping roof line has been integrated, but without any noticeable variation to the facade's materiality. Rainwater is drained away via a concealed gutter at the transition from the vertical facade to the slope.

Clay brick slip facade finish

Surrounding the inner courtyard are mostly brick, Wilhelminian-style buildings. Steimle Architects wanted to pick up on this material and recreate a close match if possible - in harmony with the existing sandstone facades in the front area of the property. In order to find the right material, many different types and colours were compared and large scale mock-ups were created.

Clever details for privacy

To prevent the roller shutters on the bathroom windows being permanently closed due to spatial proximity and privacy, the architects came up with a trick: They concealed the narrow windows behind a perforated brick detail that cleverly blends into the surrounding facade. This protects residents' privacy whilst still allowing daylight to come into the bathroom.

Energy and climate-friendly measures

The building was constructed to KfW55 standards with an external wall insulation system featuring mineral wool. The elevated green internal courtyard improves quality of living, air quality of the neighbourhood and the local microclimate. There is also a photovoltaic system on the roof, which reduces the reliance on external energy resources. Rainwater is collected and stored, and also absorbed by the green roof areas.

[ark] magazine - the StoJournal for Architects

This story appeared in [ark] magazine No.68. The planning and execution trades are responsible for ensuring compliance with local standards and regulations, as well as realising and warranting of the architectural details and solutions included in this case study. Find more project case studies like this at ark.sto.com