Case Study - Hafen Rohner

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A CASE STUDY SYDNEY GARWOOD

Photographs of the Nordwesthaus interior

The construction of the port in Fussach, Austria over the last several decades has marked a poetry between architectural construction and environmental. The Hafen Rohner port is the site of two main buildings; the harbor office building and the Nordwesthaus. The dialogue between these two ranges from form to articulation of materials. It is evident that a long-term architectural idea is guiding both of the main buildings, despite being constructed a decade apart. The present harbor site on Lake Constance was initially used as a place for gravel works (1). As this became economically challenging, property owner, Maria Rohner, converted 02

the business into a marina mostly for sailboats. Rohner commissioned the local architecture company Baumschlager Eberle (BE) for both the master plan and the harbor office and the Nordwesthaus buildings.

Maria Rohner had hired BE previously to design her personal house which resulted in a trusting relationship that positioned them for the design of the marina complex.

The first phase of the construction began in the late 1990s and was completed in the year 2000. This phase was focused on the overall site and the construction of a cantilevered concrete extrusion which holds the

office of Maria Rohner. The Rohner port expanded over the years to dock, and at present offers slips for about 180 boats (1). Phase two was then completed in 2004 which included a harbor wall to create a habitat for the wildlife and plants. This complex site is situated adjacent to an extensive nature and bird conservation area, which posed even more challenges for the design and construction (2). The project architect, Christoph von Oefele found this relationship of man-made to nature a crucial part of the project.

The dialogue of the two buildings includes the specific and precise placement of each building on the Sydney Garwood

Marina office plan and section articulating use of concrete

property. The office faces north, with its main opening looking out towards the marina and the lake framed by the Nordwesthaus. The first BE building for Maria Rohner was designed to operate as Maria Rohner’s personal office and to give visual access over the property. This allowed her to easily monitor boats traffic but also any activity in the Nordwesthaus. This main opening office overlooks the boat arrival and the majority of the boat slips in the port; the side openings of the office space are positioned specifically for Maria Rohner to be able to monitor activities in the boat yard flanking the office. The access to the office begins at ground level with stairs

leading up to the main level, at the top of the stairs the southern opening with a glass railing gives a view to the landscape before turning the corner to reach the one-room office. The glass is situated against the landscape precisely so that the shades reflect and dance on the wall perpendicular to it. The massive concrete tube overall gives a strong sense of privacy, yet the glass on both the north and south ends of the tubular structure opens up to specific views and helps to avoid claustrophobia.

Although clearly connected to the ground, the horizontally positioned rectangular concrete tube appears to

float above the ground. The concrete appears to hang precariously over a length of eight meters and it almost seems to defy the nature of gravity. In order to create the visual elegance and precision of the cantilever, beneath the surface there exists a massive foundation counterweight. This counterweight allows for the cantilever to reach a larger depth than a typical overhang. With its one-legged foot that supports the tube, the office building has been compared to a bird standing in the water; still, perched on one leg, and trying to not get wet (2). Since the building is placed in a flood zone, all essential spaces are housed inside the tube on the second level.

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Sketch of Nordwesthaus in relation to the sailboats for scale

As the port business grew, BE were once again commissioned to design another building for the marina, the Nordwesthaus. Christoph von Ofele was again assigned to be the project architect. Because of success of the office building earlier, high expectations existed especially with respect to detail and precision. The Nordwesthaus was designed as a response to the office and its placement. While the functional requirements for the office building were clearly determined, the Nordwesthaus did not have a specific program. This opened up the opportunity for exploration. The building is positioned at the end of a row of moorings, directly adjacent to the boats, using the footprint of one mooring. The verticality of the 04

structure stands alongside the sails, creating a visually balanced series of upright elements. Despite its weight and thick concrete structure, it appears to hover over the water. This is the result of a complex structure beneath the surface of the water.

The structure relies on concrete piles dug into the lake bed, which do not change between seasonal tides (2).The building can be compared to the boat in that above the water it is vulnerable, and you can see what’s going on whereas the complexity can be hidden underneath the water’s edge. Project architect, Christoph von Oefele, even describes the construction as a “boat box” (1).

Currently, the 800 sf main space offers room for about 100 people. The

building itself is placed in the water, accessed from land from the south side via a small bridge. A vertical framed opening that is offset to the right side marks the entrance. On the entry level on either side upon entering there are rest rooms, while the stairs are centered in the middle of the open space. The stairs lead into an open room standing at a height of eight meters providing a space large enough to host standing room for 100 people inside. Except for special events, there are several long wooden tables that provide seating for up to 50 guests (2).

From spring through fall, The Nordwesthaus operates with relatively a comfortable temperature without the use of mechanical systems. There are multiple hand cranks throughout Sydney Garwood

Nordwesthaus plans and section articulating use of concrete (3)

the room that allow one to manually open individual operable windows on the east and west sides for adequate ventilation.

The Nordwesthaus stands at fourteen meters tall, seven meters in width, and fourteen meters in length. The entirety of this construction consists of exposed concrete; including the rest rooms, closets and stairs. The exposed concrete is visible through the transparent glass façade which is offset from the concrete interior. This layer of glass serves as the thermal barrier while also illuminating the

light and emphasizing the exposed concrete. The play between materials poses a contrast between fragility and durability. There exists a juxtaposition of a mass of concrete and the delicate glass structure which encases it.

Although the rigid geometry of both structures in some way contrasts with the surrounding organic landscape, the Nordwesthaus offers a playful silhouette of organic shapes similar to that of a grove of trees in the water.

This form was achieved through the meticulous pouring of concrete.

The concrete had to be poured in

five stages to achieve these organic shapes. The concrete form work was designed intentionally to be reused for the entirety of the building. It only took five different form work variations to achieve the organic shapes throughout the facade. This was made possible by the thoughtful and intentional design of each piece of steel form work. They were designed to be rotated and reconfigured on site and reused for the entirety of the building. Project architect, Oefele, refers to this process and construction by saying, “This artistic perforation of the surface was taken to the limit of A Concrete Dialogue 05

A study of light in relation to the concrete in the Nordwesthaus

what is structurally possible” (2). The concrete is held by many thin steel reinforcement bars.

As a building icon on the site, the Nordwesthaus has also become a marking point of the port; acting as a lighthouse at night and helping to direct boats towards the port.

The Nordwesthaus becomes a show of light, playing off of the water and trees. The natural elements are emphasized by the building. The glass consists of an ice crystal pattern that 06

allows the light from the inside of the building to disperse softly (2). This glass was made by manually brushing repeatedly over the glass. It relied on the imperfections of the glass to create this final filtered effect. As one of the first applications of LED lighting, the illumination of the inside concrete faces can transform the building in seconds with a range of several different colors. The lights are placed to illuminate the surfaces of the concrete structure that face each other. They emphasize building

the amorphous tree-like nature of the concrete. The building with its particular lighting strategy was praised with the success of the building, saying, “Baumschlager Eberle’s new clubhouse creates a waterside kaleidoscope” (1).

Throughout the Hafen Rohner site, rigid geometries contrast with natural elements but within the subtleties of the design, there is a strong connection between man-made and nature.

Sydney Garwood

Photographs of reflections on the Hafen Rohner port office building.

Bibliography 1. “Archiweb - Rohner Harbor Office Building.” Archiweb.cz, www.archiweb.cz/en/b/kancelar-pristavurohner-hafengeb-ude-rohner.

2. “Publikationen.” Publikationen – Hafen Rohner, hafen-rohner.at/ presse/publikationen/.

3. “Home.” Home, www.baumschlager-eberle.com/.

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