BHF Berlin — Towards a More Porous and Sustainable City

Urban Vision and Concept: Recast the utopian castle as a radical porous quarter where Berlin’s past and future interlock, and small plots ignite big urban change.


Project Overview

As a utopian model for urban design, the castle offers a compelling point of departure. Its inner density and contained exterior inspire a reinterpretation of urban form that resists the freneticism of the contemporary metropolis while retaining vibrancy. Drawing from Split, Croatia—where a medieval town inhabits Diocletian’s Palace—the project explores the tension between rigidity and spontaneity, between the traces of the past and the processes of renewal.

The scheme is rooted in Berlin’s own heritage. The late nineteenth-century perimeter block—with interior courtyards shielded from the street—provides the structural base. A dense fabric is draped across the site and selectively opened to create new sub-blocks, producing a porous urban system that can evolve over time. Instead of large parcels, the plan advocates small plot divisions to foster diversity, affordability, and social resilience.

The neighbourhood becomes a mixed-use district with strong emphasis on student housing, local commerce, public courtyards, and community infrastructure. Offices occupy the rail edge to buffer noise, while David Bowie Square is programmed as a public hub anchored by a school. Streets, alleys, and courtyards structure public and semi-private life, and vegetation extends from the courtyards to the street network, stitching Hardenbergplatz, the viaduct, and the new quarter. The result is a richly layered, small-scale urbanism that channels Berlin’s history into a liveable post-pandemic city.

Street elevation fragment

Spatial Strategy

The perimeter block is retained, yet the interior is carved into a network of sub-blocks, courtyards, and alleys. Small plots encourage incremental development and programmatic diversity: student housing, ateliers, local commerce, offices, and community facilities. David Bowie Square becomes a public hub anchored by a school, while green corridors thread through the block to connect the viaduct, Hardenbergplatz, and the station. The result is a porous urban fabric that reconciles noise constraints, mobility, and climate resilience.


Axonometric view of BHF Berlin
Porous quarters grow from typological memory
Rigidity frames spontaneity
Ground floor plan of the proposal
Upper level plan of the proposal
Micro-plots keep the city adaptable
Split’s palace teaches layered living
Street elevation fragment
Interior courtyard elevation
Courtyards become civic living rooms
Courtyards stage everyday community
Perspective section through the block
Program distribution and mobility diagram
Aerial collage of the proposed quarter
Green corridors thread water, rail, and life
Vegetation stitches square, viaduct, neighbourhood

Credits

Academic project by Christian Corral at Leibniz University Hannover. Thanks to Matthias Manuel Gebhardt and Peter Matthies for discussions on small-plot urbanism and mobility.