Rakowicka 15A — designing an infill building in Kraków

Designing in the dense urban fabric of Kraków is always a compromise. Every free plot has its neighbour, its history and its constraints. The plot at Rakowicka 15A had an exceptional number of them: narrow, deep, with an existing palace on one side — a listed building on the heritage register. And a programme to fulfil: a mixed residential-commercial building that must function both commercially and spatially without dominating what is already there.

What is an infill building?

An infill building is inserted into a gap in a building line — between two existing buildings, often of entirely different characters. In Kraków, there are many such gaps: the result of wartime destruction, demolitions and unrealised developments. Designing an infill is difficult for several reasons: it cannot be aggressively modern (it would destroy the context), nor slavishly historicising (that would be a lie). It must find its own identity while respecting its neighbours.

At Rakowicka 15A, an additional factor was the presence of a 19th-century palace. The conservation officer was a party to the conversation from the start — not merely an administrative obstacle, but a real partner shaping the project.

Form from negative space

The key design decision concerned not what to build, but what not to build. The narrow plot, the immediate proximity of the palace and the need to ensure access to daylight for both buildings — both the new one and the existing one — generated a negative space: an internal courtyard between the buildings. This was not a sentimental gesture or an accident. It was a consequence of geometry and mutual relationships.

The space between "Pi" (the existing palace) and "Sigma" (the new building) became the organising element of the project. Both buildings together form a system — hence the names taken from mathematics: two different forms, a shared result.

Programme — two characters in one building

The ground floor and the palace "Pi" serve commercial functions. The upper storeys of the new "Sigma" building are residential. This division is not accidental — it follows the logic of the street and planning requirements. Commercial uses at pavement level activate the building line; apartments above benefit from distance from noise and from the view. The internal courtyard is shared — the point of contact between both functions.

Greenery as an argument

The project proposed a high proportion of permeable surface area, a ground-level garden and a green roof. This was not merely an ecological gesture — it was an argument in the conversation with the conservation officer and the planning authority. The dense development of Kraków's city centre is often criticised for its lack of greenery. The Rakowicka project tried to address that gap genuinely, not just symbolically.

What this project teaches

Rakowicka 15A is an example of a project in which constraints became generators of form. The narrow plot forced thinking about negative space. The proximity of a listed building demanded humility in terms of scale. The mixed residential-commercial programme required a precise division without either function dominating. The result — "Pi and Sigma" — is legible precisely because every constraint was taken seriously rather than bypassed.

This is a lesson relevant to every project in a historic city centre: don't fight the context. Design with the context and because of it.