This is the second in a series of articles about specific aspects of the hotel design of Miniloftmitte, written by the architects.
The west façade which faces directly onto the the street, is where the hotel's predominant defining form is most visible and distinctive. The west façade is composed of three vertical bands. The first most northerly band is made of glass; the other two are clad in stainless steel. These bands are designed to reduce the number of materials and transitions to a minimum. Because of this careful detailing the bands become monolithic surfaces, which emphasize the purity of the building's form.
The southernmost band of the west façade cantilevers out into the street at an angle. This means that on the top floors extend further into the street than Berlin's building code allows, and is one of several reasons that it took a year and a half to negotiate a building permit with the Berlin 'Stadtplanungsamt' (city planning department). We fought hard for exceptions like this because it meant we could give the building its distinctive dynamic form.
The tops of the southern and centre bands curve continuously into the roof. This compelling gesture embraces and connects the contemporary addition to the renovated nineteenth century building, to which it is adjoined at the rear.
The angles inflected by these vertical bands relate directly to the buildings on either side. In so doing the bands negotiate a dynamic formal relationship between the peaked roof residential neighbours to the north, and the flat roof university building to the south. This emphasizes the Miniloft building's urban function as a connector between two different city structures.
Design details: Glass band
The west façade's glass band is designed completely differently from the south façade (see part one of this series). While the south façade reads as a large scale screening pattern made up of alternating vertical stripes, the west façade's glass band is defined by its distinctive pattern of framing elements.
This design difference emphasizes the independence of each band, and distinguishes between the surface of the bands, and the volume they circumscribe.
The Introverted minilofts behind this glass band each have a three meter wide full height glass wall, with a french door, and a horizontal pivot window. The french doors and the railings in front of them create a rhythm which emphasizes and delineates the building's height.
Design details: Stainless steel bands
The two most southern vertical bands transition directly from wall to roof. They are clad in stainless steel to make the bands read as one surface.
Conceiving this transition was one of the defining moments of the building design. The details had to clearly express the building's formal concept at the smallest technical level to achieve the large scale effect of the bending bands.
We chose stainless steel because it was the only material that fulfilled the technical requirements of both wall and roof, and matched our aesthetic aspirations.
The steel bands are composed of horizontal strips of varying height from 15 to 59 cm. We worked closely with the tinsmith to design details for these sheet shingles; in particular, we needed an innovative solution which would allow the builders to lay the shingles top to bottom instead of the usual method of working from the bottom towards the top.
The stainless steel is press blank, which means it has not been polished. Its surface is exactly as it was when it came off the rollers at the mill. It has a supple colour, which picks up the shifting tonal spectrum of its environment. On grey days it blends in perfectly with the Berlin sky, and on sunny days it glints with a blue tinge. At the street level the steel picks up the movement of people and cars, awash in the yellows and greens of the neighbouring buildings.
The steel bands are also designed to bulge subtly. This distorts the reflections, creating amorphous images from reflected colour and movement. The steel's warm, abstract reflections provide a stark contrast to the glass band's reflections, which are cool and precise.
The design of the hotel's west façade plays with material and form to integrate the building into its urban context. It respects the past, while at the same time clearly expressing a contemporary, optimistic vision of the future. The details were carefully designed to express the three bending bands which define the building's large scale form.